1
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Chang PS, Chen BH, Lin YC, Dai WT, Kumar G, Lin YG, Huang MH. Growth of Size-Tunable Ag 2O Polyhedra and Revelation of Their Bulk and Surface Lattices. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2401558. [PMID: 38829043 DOI: 10.1002/smll.202401558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 04/22/2024] [Indexed: 06/05/2024]
Abstract
By primarily adjusting the reagent amounts, particularly the volume of AgNO3 solution introduced, Ag2O cubes with decreasing sizes from 440 to 79 nm, octahedra from 714 to 106 nm, and rhombic dodecahedra from 644 to 168 nm are synthesized. 733 nm cuboctahedra are also prepared for structural analysis. With in-house X-ray diffraction (XRD) peak calibration, shape-related peak shifts are recognizable. Synchrotron XRD measurements at 100 K reveal the presence of bulk and surface layer lattices. Bulk cell constants also deviate slightly. They show a negative thermal expansion behavior with shrinking cell constants at higher temperatures. The Ag2O crystals exhibit size- and facet-dependent optical properties. Bandgaps red-shift continuously with increasing particle sizes. Optical facet effect is also observable. Moreover, synchrotron XRD peaks of a mixture of Cu2O rhombicuboctahedra and edge- and corner-truncated cubes exposing all three crystal faces can be deconvoluted into three components with the bulk and the [111] microstrain phase as the major component. Interestingly, while the unheated Cu2O sample shows clear diffraction peak asymmetry, annealing the sample to 450 K yields nearly symmetric peaks even when returning the sample to room temperature, meaning even moderately high temperatures can permanently change the crystal lattice.
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Affiliation(s)
- Pin-Shiuan Chang
- Department of Chemistry, National Tsing Hua University, Hsinchu, 300044, Taiwan
| | - Bo-Hao Chen
- Department of Chemistry, National Tsing Hua University, Hsinchu, 300044, Taiwan
- National Synchrotron Radiation Research Center, Hsinchu, 300092, Taiwan
| | - Yu-Chang Lin
- National Synchrotron Radiation Research Center, Hsinchu, 300092, Taiwan
| | - Wan-Ting Dai
- Department of Chemistry, National Tsing Hua University, Hsinchu, 300044, Taiwan
| | - Gautam Kumar
- Department of Chemistry, National Tsing Hua University, Hsinchu, 300044, Taiwan
| | - Yan-Gu Lin
- National Synchrotron Radiation Research Center, Hsinchu, 300092, Taiwan
| | - Michael H Huang
- Department of Chemistry, National Tsing Hua University, Hsinchu, 300044, Taiwan
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2
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Chen BH, Kumar G, Wei YJ, Ma HH, Kao JC, Chou PJ, Chuang YC, Chen IC, Chou JP, Lo YC, Huang MH. Experimental Revelation of Surface and Bulk Lattices in Faceted Cu 2 O Crystals. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2303491. [PMID: 37381620 DOI: 10.1002/smll.202303491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 06/09/2023] [Indexed: 06/30/2023]
Abstract
Semiconductor crystals have generally shown facet-dependent electrical, photocatalytic, and optical properties. These phenomena have been proposed to result from the presence of a surface layer with bond-level deviations. To provide experimental evidence of this structural feature, synchrotron X-ray sources are used to obtain X-ray diffraction (XRD) patterns of polyhedral cuprous oxide crystals. Cu2 O rhombic dodecahedra display two distinct cell constants from peak splitting. Peak disappearance during slow Cu2 O reduction to Cu with ammonia borane differentiates bulk and surface layer lattices. Cubes and octahedra also show two peak components, while diffraction peaks of cuboctahedra are comprised of three components. Temperature-varying lattice changes in the bulk and surface regions also show shape dependence. From transmission electron microscopy (TEM) images, slight plane spacing deviations in surface and inner crystal regions are measured. Image processing provides visualization of the surface layer with depths of about 1.5-4 nm giving dashed lattice points instead of dots from atomic position deviations. Close TEM examination reveals considerable variation in lattice spot size and shape for different particle morphologies, explaining why facet-dependent properties are emerged. Raman spectrum reflects the large bulk and surface lattice difference in rhombic dodecahedra. Surface lattice difference can change the particle bandgap.
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Affiliation(s)
- Bo-Hao Chen
- Department of Chemistry and Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsinchu, 300044, Taiwan
- National Synchrotron Radiation Research Center, Hsinchu, 300092, Taiwan
| | - Gautam Kumar
- Department of Chemistry and Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsinchu, 300044, Taiwan
| | - Yu-Jung Wei
- Department of Chemistry, National Tsing Hua University, Hsinchu, 300044, Taiwan
| | - Hsueh-Heng Ma
- Department of Chemistry and Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsinchu, 300044, Taiwan
| | - Jui-Cheng Kao
- Department of Materials Science and Engineering, National Yang Ming Chiao Tung University, Hsinchu, 30010, Taiwan
| | - Po-Jung Chou
- Department of Chemistry and Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsinchu, 300044, Taiwan
| | - Yu-Chun Chuang
- National Synchrotron Radiation Research Center, Hsinchu, 300092, Taiwan
| | - I-Chia Chen
- Department of Chemistry, National Tsing Hua University, Hsinchu, 300044, Taiwan
| | - Jyh-Pin Chou
- Department of Physics, National Changhua University of Education, Changhua, 50007, Taiwan
| | - Yu-Chieh Lo
- Department of Materials Science and Engineering, National Yang Ming Chiao Tung University, Hsinchu, 30010, Taiwan
| | - Michael H Huang
- Department of Chemistry and Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsinchu, 300044, Taiwan
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3
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Shaik MR, Aldhuwayhi FN, Al-Mohaimeed AM, Hatshan MR, Kuniyil M, Adil SF, Khan M. Morphology Controlled Deposition of Vanadium Oxide (VO x) Nanoparticles on the Surface of Highly Reduced Graphene Oxide for the Photocatalytic Degradation of Hazardous Organic Dyes. MATERIALS (BASEL, SWITZERLAND) 2023; 16:6340. [PMID: 37763616 PMCID: PMC10532889 DOI: 10.3390/ma16186340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 09/11/2023] [Accepted: 09/14/2023] [Indexed: 09/29/2023]
Abstract
Semiconducting nanomaterials based heterogeneous photocatalysis represent a low-cost, versatile technique for environmental remediation, including pollution mitigation, energy management and other environmental aspects. Herein, we demonstrate the syntheses of various heterogeneous photocatalysts based on highly reduced graphene oxide (HRG) and vanadium oxide (VOx)-based nanocomposites (HRG-VOx). Different shapes (rod, sheet and urchin forms) of VOx nanoparticles were successfully fabricated on the surface of HRG under solvo-/hydrothermal conditions by varying the amount of water and ethanol. The high concentration of water in the mixture resulted in the formation of rod-shaped VOx nanoparticles, whereas increasing the amount of ethanol led to the production of VOx sheets. The solvothermal condition using pure ethanol as solvent produced VOx nano-urchins on the surface of HRG. The as-prepared hybrid materials were characterized using various spectroscopic and microscopic techniques, including X-ray diffraction, UV-vis, FTIR, SEM and TEM analyses. The photocatalytic activities of different HRG-VOx nanocomposites were investigated for the photodegradation of methylene blue (MB) and methyl orange (MO). The experimental data revealed that all HRG-VOx composite-based photocatalysts demonstrated excellent performance toward the photocatalytic degradation of the organic dyes. Among all photocatalysts studied, the HRG-VOx nanocomposite consisting of urchin-shaped VOx nanoparticles (HRG-VOx-U) demonstrated superior photocatalytic properties towards the degradation of dyes.
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Affiliation(s)
| | | | | | | | | | | | - Mujeeb Khan
- Department of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia; (M.R.S.); (F.N.A.); (A.M.A.-M.); (M.R.H.); (M.K.); (S.F.A.)
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4
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Jakimińska A, Spilarewicz K, Macyk W. Phototransformations of TiO 2/Ag 2O composites and their influence on photocatalytic water splitting accompanied by methanol photoreforming. NANOSCALE ADVANCES 2023; 5:1926-1935. [PMID: 36998646 PMCID: PMC10044581 DOI: 10.1039/d2na00910b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 01/19/2023] [Indexed: 06/19/2023]
Abstract
This work aimed to revise the mechanism of photocatalytic activity of the TiO2/Ag2O system in photocatalytic water splitting accompanied by methanol photoreforming. The transformation of Ag2O into silver nanoparticles (AgNPs) during photocatalytic water splitting/methanol photoreforming was monitored using XRD, XPS, SEM, UV-vis, and DRS techniques. The impact of AgNPs, grown on TiO2, on its optoelectronic properties was analysed through inter alia spectroelectrochemical measurements. The photoreduced material exhibited a significantly shifted position of the TiO2 conduction band edge. Surface photovoltage measurements revealed the lack of photoinduced exchange of electrons between TiO2 and Ag2O, indicating the absence of an efficient p-n junction. Furthermore, the impact of chemical and structural changes in the photocatalytic system on the production of CO and CO2 from methanol photoreforming was analysed. It was found that fully formed AgNPs exhibit improved efficiency in the production of H2, whereas the Ag2O phototransformation, resulting in the growth of AgNPs, promotes simultaneously ongoing photoreforming of methanol.
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Affiliation(s)
- Anna Jakimińska
- Faculty of Chemistry, Jagiellonian University ul. Gronostajowa 2 Kraków 30-387 Poland
| | - Kaja Spilarewicz
- Faculty of Chemistry, Jagiellonian University ul. Gronostajowa 2 Kraków 30-387 Poland
| | - Wojciech Macyk
- Faculty of Chemistry, Jagiellonian University ul. Gronostajowa 2 Kraków 30-387 Poland
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5
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Sagadevan S, Alshahateet SF, Anita Lett J, Fatimah I, Poonchi Sivasankaran R, Kassegn Sibhatu A, Leonardg E, Le MV, Soga T. Highly efficient photocatalytic degradation of methylene blue dye over Ag2O nanoparticles under solar light irradiation. INORG CHEM COMMUN 2022. [DOI: 10.1016/j.inoche.2022.110288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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6
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Zhang Y, Liu J, Kang YS, Zhang XL. Silver based photocatalysts in emerging applications. NANOSCALE 2022; 14:11909-11922. [PMID: 35959864 DOI: 10.1039/d2nr02665a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The infinite availability of solar energy grants the potential of fulfilling the energy demands and environmental sustainability requirements with more feasible and reliant renewable energy forms through photocatalysis. In the past decade, the intensive plasmonic effect, suitable work function, superior electrical conductivity and physiochemical properties have made Ag-based photocatalysts attractive components for emerging applications. The local surface plasmon resonance effect (LSPR) provides extra hot-carriers to participate in the photocatalytic process, and Schottky/Ohmic contacts would facilitate charge transfer. Here, recent studies focused on Ag-based photocatalysts for emerging applications are reviewed. Notably, the mechanisms of LSPR, the Schottky barrier and ohmic contacts are introduced together with urgent issues in CO2 reduction, antibacterial application, H2 generation, and environmental hazard removal. Additionally, some perspectives and directions on more comprehensive designs on material system, band alignment and functionalization are given to further the exploration in this research area.
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Affiliation(s)
- Yan Zhang
- School of Materials Science and Engineering, Zhengzhou University, 450001 Zhengzhou, P.R. China.
| | - Jian Liu
- Department of Chemical and Process Engineering, University of Surrey, GU2 7XH, UK
| | - Young Soo Kang
- Environmental and Climate Technology, Korea Institute of Energy Technology (KENTECH), 200 Hyeoksin-ro, Naju City, Jeollanamdo 58330, Korea
| | - Xiao Li Zhang
- School of Materials Science and Engineering, Zhengzhou University, 450001 Zhengzhou, P.R. China.
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7
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Gupta N, Baraiya BA, Jha PK, Soni HP. Differentiating the {100} surfaces of Cu2O nanocrystals from {111} and {110} for benzylic Csp3-H bond oxidation: Oxidations of diphenyl methane to benzophenone and cumene to cumene hydroperoxide under mild conditions. MOLECULAR CATALYSIS 2022. [DOI: 10.1016/j.mcat.2022.112490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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8
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Yang SJ, Lin YK, Pu YC, Hsu YJ. Crystal Facet Dependent Energy Band Structures of Polyhedral Cu 2O Nanocrystals and Their Application in Solar Fuel Production. J Phys Chem Lett 2022; 13:6298-6305. [PMID: 35786932 DOI: 10.1021/acs.jpclett.2c01632] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
We demonstrated a facile hydrothermal method to synthesize the (100)-, (110)- and (111)-oriented Cu2O nanocrystals (NCs) by controlling the concentration of the incorporated anions (CO32- and SO32-). The crystal facet dependent activity of the orientation controlled Cu2O NCs in the rhodamine B (RhB) photodegradation and photocatalytic hydrogen (H2) evolution was found to follow the trend: (111) > (110) > (100). The mechanism was investigated by characterizing the optical property, energy band structure, interfacial charge carrier dynamics and reducing ability. The results indicated that the (111)-oriented Cu2O NCs exhibit the higher conduction band (CB) potential as compared with the (110)-oriented and (100)-oriented Cu2O NCs, which resulted in the largest driving force of interfacial electron transfer for (111)-oriented Cu2O NCs to carry out solar fuel generation. The current study offers an easy strategy for crystal facet engineering of semiconductors and provides important physical insights into their electronic properties for the desired solar energy conversions.
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Affiliation(s)
- Shan-Jen Yang
- Department of Materials Science, National University of Tainan, Tainan 70005, Taiwan
| | - Yin-Kai Lin
- Department of Materials Science and Engineering, National Yang Ming Chiao Tung University, Hsinchu, Taiwan 30010, Taiwan
| | - Ying-Chih Pu
- Department of Materials Science, National University of Tainan, Tainan 70005, Taiwan
| | - Yung-Jung Hsu
- Department of Materials Science and Engineering, National Yang Ming Chiao Tung University, Hsinchu, Taiwan 30010, Taiwan
- Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
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9
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Lv YR, Wang ZL, Yang YX, Luo Y, Yang SY, Xu YH. Tin bisulfide nanoplates anchored onto flower-like bismuth tungstate nanosheets for enhancement in the photocatalytic degradation of organic pollutant. JOURNAL OF HAZARDOUS MATERIALS 2022; 432:128665. [PMID: 35334268 DOI: 10.1016/j.jhazmat.2022.128665] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 02/07/2022] [Accepted: 03/08/2022] [Indexed: 06/14/2023]
Abstract
The development of efficient heterojunctions through a simple and facile method is an effective way to enhance the photocatalytic performance of bismuth-based oxide semiconductors for industrial applications. Here, the novel flower-like type II SnS2/Bi2WO6 heterostructure consisting of bismuth tungstate (Bi2WO6) nanosheets and tin bisulfide (SnS2) nanoplates was successfully designed and synthesized. The crystal structure, composition, morphology, and photoelectric properties of the heterostructure were systematically characterized. In addition, the photocatalytic activity of SnS2/Bi2WO6 was analyzed and compared with Bi2WO6 or SnS2 alone or physical mixture of SnS2 and Bi2WO6. 2%SnS2/Bi2WO6 presents a 3.1 times greater degradation rate constant (0.0065 min-1) than that of Bi2WO6 (0.0021 min-1) under low visible light irradiation (5.3 mW·cm-2, a 44 W LED), while SnS2 alone exhibits no photocatalytic effect toward glyphosate. Furthermore, 2%SnS2/Bi2WO6 maintains 93% of its original photocatalytic activity even after four cycles. The possible photocatalytic degradation pathway of glyphosate and photocatalytic mechanism are also proposed. The excellent photocatalytic performance of SnS2/Bi2WO6 is attributed to the decoration of SnS2 nanoplates on the surface of Bi2WO6, appropriate (113)/(020) ratio, increased visible-light absorption, and effective separation of photoinduced carriers. This paper reports a new methodology that can act as a reference basis to design and develop visible-light responsive photocatalysts with outstanding photocatalytic performance for carbon dioxide reduction, water splitting, and pollutant degradation.
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Affiliation(s)
- Yan-Ran Lv
- Key Laboratory for Biobased Materials and Energy of Ministry of Education, College of Materials and Energy, South China Agricultural University, Guangzhou 510642, China
| | - Zhi-Lin Wang
- Key Laboratory for Biobased Materials and Energy of Ministry of Education, College of Materials and Energy, South China Agricultural University, Guangzhou 510642, China
| | - Yuan-Xin Yang
- Key Laboratory for Biobased Materials and Energy of Ministry of Education, College of Materials and Energy, South China Agricultural University, Guangzhou 510642, China
| | - Ying Luo
- Key Laboratory for Biobased Materials and Energy of Ministry of Education, College of Materials and Energy, South China Agricultural University, Guangzhou 510642, China
| | - Si-Yuan Yang
- Key Laboratory for Biobased Materials and Energy of Ministry of Education, College of Materials and Energy, South China Agricultural University, Guangzhou 510642, China
| | - Yue-Hua Xu
- Key Laboratory for Biobased Materials and Energy of Ministry of Education, College of Materials and Energy, South China Agricultural University, Guangzhou 510642, China.
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10
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Li W, Zhao JW, Yan C, Dong B, Zhang Y, Li W, Zai J, Li GR, Qian X. Asymmetric Activation of the Nitro Group over a Ag/Graphene Heterointerface to Boost Highly Selective Electrocatalytic Reduction of Nitrobenzene. ACS APPLIED MATERIALS & INTERFACES 2022; 14:25478-25489. [PMID: 35634976 DOI: 10.1021/acsami.2c04533] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The electrocatalytic reduction of nitrobenzene to aniline normally faces high overpotential and poor selectivity because of its six-electron redox nature. Herein, a Ag nanoparticles/laser-induced-graphene (LIG) heterointerface was fabricated on polyimide films and employed as an electrode material for an efficient nitrobenzene reduction reaction (NBRR) via a one-step laser direct writing technology. The first-principles calculations reveal that Ag/LIG shows the lowest activation barriers for the NBRR, which could be attributed to the optimum adsorption of the H atom realized by the appropriate interaction between Ag/LIG heterointerfaces and nitrobenzene. As a result, the overpotential of the NBRR is reduced by 217 mV after silver loading, and Ag/LIG shows a high aniline selectivity of 93%. Furthermore, an electrochemical reduction of nitrobenzene in tandem with an electrochemical oxidative polymerization of aniline was designed to serve as an alternative method to remove nitrobenzene from the aqueous solution. This strategy highlights the significance of heterointerfaces for efficient electrocatalysts, which may stimulate the development of novel electrocatalysts to boost the electrocatalytic activity.
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Affiliation(s)
- Wenqian Li
- Shanghai Electrochemical Energy Devices Research Center, School of Chemistry and Chemical Engineering and State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University Shanghai, Shanghai 200240, P. R. China
| | - Jia-Wei Zhao
- School of Chemistry, Sun Yat-sen University, Guangzhou 510275, China
| | - Changyu Yan
- Shanghai Electrochemical Energy Devices Research Center, School of Chemistry and Chemical Engineering and State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University Shanghai, Shanghai 200240, P. R. China
| | - Boxu Dong
- Shanghai Electrochemical Energy Devices Research Center, School of Chemistry and Chemical Engineering and State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University Shanghai, Shanghai 200240, P. R. China
| | - Yuchi Zhang
- Shanghai Electrochemical Energy Devices Research Center, School of Chemistry and Chemical Engineering and State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University Shanghai, Shanghai 200240, P. R. China
| | - Wenjing Li
- Shanghai Electrochemical Energy Devices Research Center, School of Chemistry and Chemical Engineering and State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University Shanghai, Shanghai 200240, P. R. China
| | - Jiantao Zai
- Shanghai Electrochemical Energy Devices Research Center, School of Chemistry and Chemical Engineering and State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University Shanghai, Shanghai 200240, P. R. China
| | - Gao-Ren Li
- School of Chemistry, Sun Yat-sen University, Guangzhou 510275, China
| | - Xuefeng Qian
- Shanghai Electrochemical Energy Devices Research Center, School of Chemistry and Chemical Engineering and State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University Shanghai, Shanghai 200240, P. R. China
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11
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Origin and manifestation of semiconductor facet effects. J CHIN CHEM SOC-TAIP 2022. [DOI: 10.1002/jccs.202200115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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12
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Zangiabadi M, Mehrabi F, Nasiripur P, Baghersad MH. Visible-light-driven photocatalytic degradation of methyl parathion as chemical warfare agent simulant by NiO/Bi2MoO6 heterojunction photocatalyst. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.132472] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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13
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Tan CS, Huang MH. Surface-dependent band structure variations and bond deviations of GaN. Phys Chem Chem Phys 2022; 24:9135-9140. [PMID: 35403651 DOI: 10.1039/d2cp00100d] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Density functional theory (DFT) calculations on a tunable number of GaN (0001) planes give an invariant band structure, density of states (DOS) diagram, and band gap of the GaN unit cell. Dissimilar band structures and DOS diagrams are obtained for 1, 3, 5, 7, and 9 layers of GaN (101̄0) planes, but the same band structure as that of the (0001) plane returns for 2, 4, 6, and 8 (101̄0) planes. Furthermore, 1 to 4 layers of GaN (101̄1) planes exhibit dissimilar band structures, but the GaN unit cell band structure is obtained for 5 (101̄1) planes. While there are no changes to the Ga-N bond length and bond geometry for the (0001) planes, the (101̄0) planes present bond length variation and bond distortion with odd numbers of layers. Bond length and bond direction deviations are also obtained for 1 to 4 (101̄1) planes. These results suggest that slight structural deviations may be present near the GaN surface to produce facet-dependent properties, and such atomic position deviations in the surface layer can be observed in various semiconductors.
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Affiliation(s)
- Chih-Shan Tan
- Institute of Electronics, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan.
| | - Michael H Huang
- Department of Chemistry, National Tsing Hua University, Hsinchu 300044, Taiwan.
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14
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Thangavel S, Pazhamalai P, Krishnamoorthy K, Sivalingam Y, Arulappan D, Mohan V, Kim SJ, Venugopal G. Ferroelectric-semiconductor BaTiO 3-Ag 2O nanohybrid as an efficient piezo-photocatalytic material. CHEMOSPHERE 2022; 292:133398. [PMID: 34954192 DOI: 10.1016/j.chemosphere.2021.133398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 11/30/2021] [Accepted: 12/20/2021] [Indexed: 06/14/2023]
Abstract
Piezo-photocatalysis is a new concept of utilizing nanohybrids comprising piezoelectric and photocatalytic materials for enhancement in advanced oxidation process under the presence of light and mechanical energy. In this study, we explored the effectiveness of piezo-photocatalysis via examining their catalytic activity towards the degradation of azo dye (Rhodamine-B) and standard pollutant (Phenol) catalyzed by ferroelectric-semiconductor (BaTiO3-Ag2O) nanohybrids. Further, the enhancement in piezo-photocatalysis has been achieved via persulfate activation and the role of free radicals was examined by quenchers. A plausible mechanism for the improved piezo-photocatalysis of BaTiO3-Ag2O nanohybrid using persulfate activation has been discussed in detail. The removal mechanism of Rhodamine-B has been investigated using analytical techniques such as HPLC and EPR. Our experimental study demonstrated that the combination of piezo-photocatalysis with persulfate activation will provide higher reaction rate which will be beneficial towards the degradation of complex molecular pollutants derived from industrial sectors.
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Affiliation(s)
- Sakthivel Thangavel
- Nanomaterials & System Lab, Major of Mechatronics Engineering, Faculty of Applied Energy System, Jeju National University, Jeju, 63243, South Korea; State Key Laboratory for Mechanical Behavior of Materials, Xian Jiaotong University, Xi'an, 710049, Shaanxi, China
| | - Parthiban Pazhamalai
- Nanomaterials & System Lab, Major of Mechatronics Engineering, Faculty of Applied Energy System, Jeju National University, Jeju, 63243, South Korea
| | - Karthikeyan Krishnamoorthy
- Nanomaterials & System Lab, Major of Mechatronics Engineering, Faculty of Applied Energy System, Jeju National University, Jeju, 63243, South Korea
| | - Yuvaraj Sivalingam
- Laboratory for Sensors, Energy and Electronic Devices, Department of Physics and Nanotechnology, SRM Institute of Science and Technology, Kattankulathur, Chennai, 603203, India
| | - Durairaj Arulappan
- School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Vigneshwaran Mohan
- Nanomaterials & System Lab, Major of Mechatronics Engineering, Faculty of Applied Energy System, Jeju National University, Jeju, 63243, South Korea; Department of Materials Science, School of Technology, Central University of Tamil Nadu, Thiruvarur, 610 005, Tamil Nadu, India
| | - Sang-Jae Kim
- Nanomaterials & System Lab, Major of Mechatronics Engineering, Faculty of Applied Energy System, Jeju National University, Jeju, 63243, South Korea; Nanomaterials & System Lab, Major of Mechanical System Engineering, College of Engineering, Jeju National University, Jeju, 63243, South Korea; Research Institute of Energy New Industry, Jeju National University, Jeju, 63243, South Korea.
| | - Gunasekaran Venugopal
- Department of Materials Science, School of Technology, Central University of Tamil Nadu, Thiruvarur, 610 005, Tamil Nadu, India.
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15
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Hosseini M, Chin AWH, Williams MD, Behzadinasab S, Falkinham JO, Poon LLM, Ducker WA. Transparent Anti-SARS-CoV-2 and Antibacterial Silver Oxide Coatings. ACS APPLIED MATERIALS & INTERFACES 2022; 14:8718-8727. [PMID: 35138100 PMCID: PMC8848512 DOI: 10.1021/acsami.1c20872] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 01/14/2022] [Indexed: 05/17/2023]
Abstract
Transparent antimicrobial coatings can maintain the aesthetic appeal of surfaces and the functionality of a touch-screen while adding the benefit of reducing disease transmission. We fabricated an antimicrobial coating of silver oxide particles in a silicate matrix on glass. The matrix was grown by a modified Stöber sol-gel process with vapor-phase water and ammonia. A coating on glass with 2.4 mg of Ag2O per mm2 caused a reduction of 99.3% of SARS-CoV-2 and >99.5% of Pseudomonas aeruginosa, Staphylococcus aureus, and methicillin-resistant Staphylococcus aureus compared to the uncoated glass after 1 h. We envisage that screen protectors with transparent antimicrobial coatings will find particular application to communal touch-screens, such as in supermarkets and other check-out or check-in facilities where a number of individuals utilize the same touch-screen in a short interval.
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Affiliation(s)
- Mohsen Hosseini
- Dept. of Chemical Engineering and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, Virginia, 24061, USA
| | - Alex W. H. Chin
- School of Public Health, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, Hong Kong, China
- Centre for Immunity and Infection, Hong Kong Science Park, Hong Kong, Hong Kong, China
| | - Myra D. Williams
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, 24061, USA
| | - Saeed Behzadinasab
- Dept. of Chemical Engineering and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, Virginia, 24061, USA
| | - Joseph O. Falkinham
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, 24061, USA
| | - Leo L. M. Poon
- School of Public Health, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, Hong Kong, China
- Centre for Immunity and Infection, Hong Kong Science Park, Hong Kong, Hong Kong, China
- HKU-Pasteur Research Pole, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - William A. Ducker
- Dept. of Chemical Engineering and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, Virginia, 24061, USA
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16
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Lin E, Wu J, Kang Z, Qin N, Ke K, Bao D. Synergistic Enhancement of Piezocatalytic Activity of BaTiO 3 Convex Polyhedrons Nanocomposited with Ag NPs/Co 3O 4 QDs Cocatalysts. ACS APPLIED MATERIALS & INTERFACES 2022; 14:5223-5236. [PMID: 35067059 DOI: 10.1021/acsami.1c19287] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Piezocatalysis is one of the green and promising catalytic technologies for the degradation of organic pollutants. Surface modifications such as exposed facet engineering and surface decoration of nanoparticles (NPs) are simple but useful enhancement strategies for a catalytic system. However, the synergistic effect and mechanism of facet engineering and dual-cocatalyst decoration on piezocatalytic activity are still ambiguous and more investigations are expected. Herein, the piezocatalytic activities of BaTiO3 (BTO) polyhedrons with anisotropic {001} and {110} facets and BTO cubes with isotropic {001} facets were compared. Furthermore, BaTiO3 (BTO) convex polyhedrons with selectively deposited Ag NPs and uniformly loaded Co3O4 quantum dots (QDs) are rationally synthesized through photochemical deposition. The individual and synergistic effects of Ag NPs and Co3O4 QDs on the piezocatalytic activities are systematically studied. It was found that dual-cocatalyst-modified BTO possesses the highest piezocatalytic activity in methyl orange degradation, with a reaction constant k of 0.0539 min-1, around 5, 2.2, and 1.3 times higher than that of nonmodified and Ag NP- and Co3O4 QD-modified BTO, respectively. Moreover, dual-cocatalyst-decorated BTO also exhibits excellent piezocatalytic performance in nondye pollutant degradation, with ∼100% tetracycline hydrochloride decomposed in 60 min. By analyzing the contribution, quantifying the amount of different free radicals, and comparing the chemical states of surface elements before and after piezocatalytic measurements, it was inferred that facet-dependent Ag NPs acted as efficient electron-transport sites, while uniformly loaded Co3O4 QDs served as hole-transfer sites to fully facilitate the migration of electrons and holes in a piezocatalytic reaction. This research presents a rational and effectual modification strategy to enhance the piezocatalytic activity of piezocatalysts and gives a thorough discussion of the enhanced mechanism.
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Affiliation(s)
- Enzhu Lin
- State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China
| | - Jiang Wu
- State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China
| | - Zihan Kang
- State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China
| | - Ni Qin
- State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China
| | - Kanghui Ke
- State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China
| | - Dinghua Bao
- State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China
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17
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Wang H, Li X, Zhao X, Li C, Song X, Zhang P, Huo P, Li X. A review on heterogeneous photocatalysis for environmental remediation: From semiconductors to modification strategies. CHINESE JOURNAL OF CATALYSIS 2022. [DOI: 10.1016/s1872-2067(21)63910-4] [Citation(s) in RCA: 108] [Impact Index Per Article: 54.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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18
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Nieves LM, Mossburg K, Hsu JC, Maidment ADA, Cormode DP. Silver chalcogenide nanoparticles: a review of their biomedical applications. NANOSCALE 2021; 13:19306-19323. [PMID: 34783806 PMCID: PMC8647685 DOI: 10.1039/d0nr03872e] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Silver chalcogenide (Ag2X, where X = S, Se, or Te) nanoparticles have been extensively investigated for their applications in electronics but have only recently been explored for biomedical applications. In the past 10 years, Ag2X, primarily silver sulfides at first, have become of great importance as quantum dots, since they not only possess excellent deep tissue imaging properties in the near-infrared regions I and II, but also have low toxicities. Their appealing properties have led to numerous recent developments of Ag2X for biomedical applications. Furthermore, Ag2X have been discovered in the past 2-3 years to be potent X-ray contrast agents, adding to the numerous biomedical uses of these nanoparticles. In this review, we discuss the most recent advances in silver chalcogenide nanoparticle use in areas such as bio-imaging, theranostics, and biosensors. Moreover, we examine the advances in synthetic approaches for these nanoparticles, which include aqueous and organic syntheses routes. Finally, we discuss the advantages and current limitations in the use of silver chalcogenides for different biomedical applications and their potential for advancement and expansions in use.
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Affiliation(s)
- Lenitza M Nieves
- Biochemistry and Molecular Biophysics Graduate Group, University of Pennsylvania, Philadelphia, PA, USA
- Radiology Department, University of Pennsylvania, Philadelphia, PA, USA.
| | - Katherine Mossburg
- Radiology Department, University of Pennsylvania, Philadelphia, PA, USA.
- Bioengineering Department, University of Pennsylvania, Philadelphia, PA, USA
| | - Jessica C Hsu
- Radiology Department, University of Pennsylvania, Philadelphia, PA, USA.
- Bioengineering Department, University of Pennsylvania, Philadelphia, PA, USA
| | | | - David P Cormode
- Radiology Department, University of Pennsylvania, Philadelphia, PA, USA.
- Bioengineering Department, University of Pennsylvania, Philadelphia, PA, USA
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19
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Lee AT, Tan CS, Huang MH. Current Rectification and Photo-Responsive Current Achieved through Interfacial Facet Control of Cu 2O-Si Wafer Heterojunctions. ACS CENTRAL SCIENCE 2021; 7:1929-1937. [PMID: 34841063 PMCID: PMC8614108 DOI: 10.1021/acscentsci.1c01067] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Indexed: 06/13/2023]
Abstract
Conductive atomic force microscopy (C-AFM) was employed to perform conductivity measurements on a facet-specific Cu2O cube, octahedron, and rhombic dodecahedron and intrinsic Si {100}, {111}, and {110} wafers. Similar I-V curves to those recorded previously using a nanomanipulator were obtained with the exception of high conductivity for the Si {110} wafer. Next, I-V curves of different Cu2O-Si heterostructures were evaluated. Among the nine possible arrangements, Cu2O octahedron/Si {100} wafer and Cu2O octahedron/Si {110} wafer combinations show good current rectification behaviors. Under white light illumination, Cu2O cube/Si {110} wafer and Cu2O rhombic dodecahedron/Si {111} wafer combinations exhibit the largest degrees of photocurrent, so such interfacial plane-controlled semiconductor heterojunctions with light sensitivity can be applied to make photodetectors. Adjusted band diagrams are presented highlighting different interfacial band bending situations to facilitate or inhibit current flow for different Cu2O-Si junctions. More importantly, the observation of clear current-rectifying effects produced at the semiconductor heterojunctions with properly selected contacting faces or planes implies that novel field-effect transistors (FETs) can be fabricated using this design strategy, which should integrate well with current chip manufacturing processes.
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Affiliation(s)
- An-Ting Lee
- Department
of Chemistry and Frontier Research Center on Fundamental and Applied
Sciences of Matters, National Tsing Hua
University, 101, Sec. 2, Kuang Fu Road, Hsinchu 30013, Taiwan
| | - Chih-Shan Tan
- Institute
of Electronics, National Yang Ming Chiao
Tung University, 1001 University Road, Hsinchu 30010, Taiwan
| | - Michael H. Huang
- Department
of Chemistry and Frontier Research Center on Fundamental and Applied
Sciences of Matters, National Tsing Hua
University, 101, Sec. 2, Kuang Fu Road, Hsinchu 30013, Taiwan
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20
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Zhang W, Song K, Ding R, Han H, Yao L, Ji M, Chen Z, Yu H, Wu C, Fang T. Role of polystyrene microplastics in sunlight-mediated transformation of silver in aquatic environments: Mechanisms, kinetics and toxicity. JOURNAL OF HAZARDOUS MATERIALS 2021; 419:126429. [PMID: 34174620 DOI: 10.1016/j.jhazmat.2021.126429] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 05/19/2021] [Accepted: 06/16/2021] [Indexed: 06/13/2023]
Abstract
Sunlight-oxidative ageing is a common and critical process for microplastics (MPs) in aquatic environments. O2•-, 1O2, and •OH generation has been widely proven in this process, which can alter metal speciation based on its reduction and oxidation potential. Herein, chemical speciation of Ag mediated by polystyrene (PS) MPs was determined under simulated sunlight irradiation. The O2•- generation on the PS MPs surfaces is the vital factor for Ag+ reduction, regardless of acid or base conditions. The 1O2 and •OH are dominant factors, and 1O2 played a more important role than •OH for its higher formation amount, causing oxidative dissolution of newly formed Ag0 nanoparticles (NPs). The Ag NPs can hetero-aggregate with PS MPs through electrostatic interactions with O-containing groups (C-O, C-OH and CO), and co-precipitate from the water phase. This hetero-aggregation can stabilize Ag NPs by inhibiting Ag NPs surface photooxidation and suppressing Ag+ release. Transformation of Ag species (from Ag+ to Ag0 NPs) mediated by sunlight with PS MPs significantly suppressed acute toxicity of Ag+ to Escherichia coli, Selenastrum capricornutum, Daphnia magna and zebrafish. This study emphasized that PS MPs play an important role in the speciation, migration and toxicity of Ag+ in freshwater environments.
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Affiliation(s)
- Weicheng Zhang
- Henan Provincial Academician Workstation of Water Security for Water Source Region of Mid-line of South-to-North Diversion Project, Nanyang Normal University, Nanyang 473061, China; Collaborative Innovation Center of Water Security for Water Source Region of Mid-line of South-to-North Diversion Project of Henan Province, Nanyang Normal University, Nanyang 473061, China
| | - Ke Song
- Henan Provincial Academician Workstation of Water Security for Water Source Region of Mid-line of South-to-North Diversion Project, Nanyang Normal University, Nanyang 473061, China; Collaborative Innovation Center of Water Security for Water Source Region of Mid-line of South-to-North Diversion Project of Henan Province, Nanyang Normal University, Nanyang 473061, China
| | - Runrun Ding
- Henan Provincial Academician Workstation of Water Security for Water Source Region of Mid-line of South-to-North Diversion Project, Nanyang Normal University, Nanyang 473061, China; Collaborative Innovation Center of Water Security for Water Source Region of Mid-line of South-to-North Diversion Project of Henan Province, Nanyang Normal University, Nanyang 473061, China
| | - Hui Han
- Henan Provincial Academician Workstation of Water Security for Water Source Region of Mid-line of South-to-North Diversion Project, Nanyang Normal University, Nanyang 473061, China; Collaborative Innovation Center of Water Security for Water Source Region of Mid-line of South-to-North Diversion Project of Henan Province, Nanyang Normal University, Nanyang 473061, China
| | - Lunguang Yao
- Henan Provincial Academician Workstation of Water Security for Water Source Region of Mid-line of South-to-North Diversion Project, Nanyang Normal University, Nanyang 473061, China; Collaborative Innovation Center of Water Security for Water Source Region of Mid-line of South-to-North Diversion Project of Henan Province, Nanyang Normal University, Nanyang 473061, China
| | - Mingfei Ji
- Henan Provincial Academician Workstation of Water Security for Water Source Region of Mid-line of South-to-North Diversion Project, Nanyang Normal University, Nanyang 473061, China; Collaborative Innovation Center of Water Security for Water Source Region of Mid-line of South-to-North Diversion Project of Henan Province, Nanyang Normal University, Nanyang 473061, China
| | - Zhaojin Chen
- Henan Provincial Academician Workstation of Water Security for Water Source Region of Mid-line of South-to-North Diversion Project, Nanyang Normal University, Nanyang 473061, China; Collaborative Innovation Center of Water Security for Water Source Region of Mid-line of South-to-North Diversion Project of Henan Province, Nanyang Normal University, Nanyang 473061, China
| | - Haiying Yu
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua 321004, China
| | - Chenxi Wu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; China University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Tao Fang
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; China University of Chinese Academy of Sciences, Beijing 100049, China.
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21
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Sboui M, Lachheb H, Bouattour S, Gruttadauria M, La Parola V, Liotta LF, Boufi S. TiO 2/Ag 2O immobilized on cellulose paper: A new floating system for enhanced photocatalytic and antibacterial activities. ENVIRONMENTAL RESEARCH 2021; 198:111257. [PMID: 33974837 DOI: 10.1016/j.envres.2021.111257] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 03/06/2021] [Accepted: 04/26/2021] [Indexed: 06/12/2023]
Abstract
Paper-TiO2-Ag2O floating photocatalysts were produced under mild condition and their photocatalytic activity for the degradation of aromatic amine under sunlight stimulant was investigated. Characterizations by Raman, XRD, XPS, DRS and PL confirmed the presence of TiO2 and Ag2O, and the morphology of the appended TiO2/Ag2O layer was probed by FE-SEM. The photocatalytic activity of the prepared samples was investigated by the degradation of aniline (AN) in water under simulated sun-light illumination and constrained conditions, i.e. non-stirring and non-oxygenation. The presence of Ag2O combined with TiO2 was shown to improve the resistance of paper to bacteria attack, thus increasing the durability of the photocatalyst. Thanks to its hydrophobic character, the paper-TiO2-Ag2O NPs can be employed as useful floating photocatalyst and can be reused in continuous cycles.
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Affiliation(s)
- Mouheb Sboui
- Faculty of Sciences, University of Sfax, Laboratoire de Chimie Inorganique (LCI), Sfax BP1171-3018, Tunisia.
| | - Hinda Lachheb
- URCMEP (UR11ES85), Faculty of Sciences, University of Gabès, 6029, Gabès, Tunisia
| | - Soraa Bouattour
- Faculty of Sciences, University of Sfax, Laboratoire de Chimie Inorganique (LCI), Sfax BP1171-3018, Tunisia
| | - Michelangelo Gruttadauria
- Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF), Università degli Studi di Palermo, Viale delle Scienze, Ed. 17, 90128, Palermo, Italy
| | - Valeria La Parola
- Istituto per lo Studio dei Materiali Nanostrutturati (ISMN-CNR), Via Ugo La Malfa 153, 90146, Palermo, Italy
| | - Leonarda Francesca Liotta
- Istituto per lo Studio dei Materiali Nanostrutturati (ISMN-CNR), Via Ugo La Malfa 153, 90146, Palermo, Italy.
| | - Sami Boufi
- Faculty of Sciences, University of Sfax, Laboratoire Sciences des Matériaux et Environnement (LSME), Sfax BP1171-3018, Tunisia.
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22
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Bai L, Chang Y, Zong S. Effort of ionic radius on doped style of silver and copper/zinc oxide nanorods for photodegradation of methylene blue. ENVIRONMENTAL TECHNOLOGY 2021; 43:1-9. [PMID: 34092200 DOI: 10.1080/09593330.2021.1939793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 05/29/2021] [Indexed: 06/12/2023]
Abstract
The homogeneous Cu-ZnO and heterogeneous Ag/ZnO nanorods were synthesised by controlling the ionic radius of Cu and Ag with lattice of ZnO. The structure of Cu-ZnO and Ag/ZnO was investigated by a series of methods. The study of the photoelectric properties suggested both the homogeneously and heterogeneously doped ZnO displayed an increased photocatalytic performance. It was worth noting that the Cu-ZnO and Ag/ZnO composites shown different degradation activities of methylene blue under the visible and UV light irradiation. The data suggested that the Cu species incorporated into the crystal lattice of ZnO nanorods could promote the utilisation of visible light, leading to 2.5- and 2.7-fold increase in the degradation rates compared with Ag/ZnO and ZnO nanorods. However, when UV light was employed, on the one hand, the significant increase of the activity for both Cu-ZnO and Ag/ZnO compared with ZnO was observed and on the other hand, the degradation rate of Cu-ZnO was close to that of Ag/ZnO. The investigation suggested that the metallic Cu in the ZnO crystal lattice could promote the separation of electrons and holes generated by ZnO under visible light. As for the UV light, both doping styles could favour the separation process. The present work could provide a further insight for the design of ZnO-based nanomaterials and development of their applications in environmental catalysis.
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Affiliation(s)
- Lei Bai
- College of Chemistry and Materials Engineering, Anhui Science and Technology University, Bengbu, People's Republic of China
| | - Yuting Chang
- College of Chemistry and Materials Engineering, Anhui Science and Technology University, Bengbu, People's Republic of China
| | - Shikun Zong
- College of Chemistry and Materials Engineering, Anhui Science and Technology University, Bengbu, People's Republic of China
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23
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Zhang T, Shang H, Zhang B, Yan D, Xiang X. Ag/Ultrathin-Layered Double Hydroxide Nanosheets Induced by a Self-Redox Strategy for Highly Selective CO 2 Reduction. ACS APPLIED MATERIALS & INTERFACES 2021; 13:16536-16544. [PMID: 33793186 DOI: 10.1021/acsami.1c02737] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The carbon-neutral photocatalytic CO2 reduction reaction (CO2RR) enables the conversion of CO2 into hydrocarbon fuels or value-added chemicals under mild conditions. Achieving high selectivity for the desired products of the CO2RR remains challenging. Herein, a self-redox strategy is developed to construct strong interfacial bonds between Ag nanoparticles and an ultrathin CoAl-layered double hydroxide (U-LDH) nanosheet support, where the surface hydroxyl groups associated with oxygen vacancies of U-LDH play a critical role in the formation of the interface structure. The supported Ag@U-LDH acts as a highly efficient catalyst for CO2 reduction, resulting in a high CO evolution rate of 757 μmol gcat-1 h-1 and a CO selectivity of 94.5% under light irradiation. Such a high catalytic selectivity may represent a new record among current photocatalytic CO2RR to CO systems. The Ag-O-Co interface bonding is confirmed by Fourier-transform infrared (FTIR) spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, and FTIR CO2 adsorption studies. The in situ FTIR measurements indicate that the formation of the *COOH intermediate is accelerated and the mass transfer is improved during the CO2RR. Density functional theory calculations show that the Ag-O-Co interface reduces the formation energy of the *COOH intermediate and accumulates localized charge. Experimental and theoretical analysis collectively demonstrates that the strong interface bonding between Ag and U-LDH activates the interface structure as catalytically CO2RR active sites, effectively optimizing the binding energies with reacted intermediates and facilitating the CO2RR performance.
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Affiliation(s)
- Tingting Zhang
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
| | - Huishan Shang
- School of Chemical Engineering, Zhengzhou University, Zhengzhou 450001, People's Republic of China
| | - Bing Zhang
- School of Chemical Engineering, Zhengzhou University, Zhengzhou 450001, People's Republic of China
| | - Dongpeng Yan
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, People's Republic of China
| | - Xu Xiang
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
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24
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Shang Y, Sun L, Wang H, Li S, Cao K, Huo P. Azobenzene-modified Ag/Ag 2O/CN photocatalysts with photoresponsive performance for controllable photodegradation of tetracyclines. NEW J CHEM 2021. [DOI: 10.1039/d1nj00933h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this work, an Azo@Ag/Ag2O/CN composite photocatalyst with light-responsive performance was successfully prepared by precipitation and emulsion polymerization. Azo@Ag/Ag2O/CN exhibits cis-trans isomerism under different light exposures.
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Affiliation(s)
- Ye Shang
- School of Chemistry
- Zhengzhou University
- Zhengzhou 450001
- P. R. China
- School of Chemical and Environmental Engineering
| | - Linlin Sun
- School of Chemistry and Chemical Engineering
- Jiangsu University
- Zhenjiang 212013
- P. R. China
| | - Huiqin Wang
- School of Energy and Power Engineering
- Jiangsu University
- Zhenjiang 212013
- P. R. China
| | - Songtian Li
- School of Chemistry
- Zhengzhou University
- Zhengzhou 450001
- P. R. China
- School of Chemical and Environmental Engineering
| | - Kesheng Cao
- School of Chemical and Environmental Engineering
- Pingdingshan University
- Pingdingshan 467000
- P. R. China
| | - Pengwei Huo
- School of Chemistry and Chemical Engineering
- Jiangsu University
- Zhenjiang 212013
- P. R. China
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25
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Tan CS, Huang MH. Surface-dependent band structure variations and bond-level deviations in Cu2O. Inorg Chem Front 2021. [DOI: 10.1039/d1qi00733e] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
New DFT calculations revealed notable variations in the band gap, bond length and bond geometry in different planes of Cu2O, which helped in understanding its various facet-dependent behaviors.
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Affiliation(s)
- Chih-Shan Tan
- Institute of Electronics, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
| | - Michael H. Huang
- Department of Chemistry and Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsinchu 30013, Taiwan
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26
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Zhang XF, Li JS, You WS, Zhu ZM. Ag2−O with highly exposed {111} crystal facets for efficient electrochemical oxygen evolution: Activity and mechanism. CHINESE JOURNAL OF CATALYSIS 2020. [DOI: 10.1016/s1872-2067(20)63574-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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27
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Sun S, Zhang X, Cui J, Liang S. Identification of the Miller indices of a crystallographic plane: a tutorial and a comprehensive review on fundamental theory, universal methods based on different case studies and matters needing attention. NANOSCALE 2020; 12:16657-16677. [PMID: 32766646 DOI: 10.1039/d0nr03637d] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Micro-/nanostructures exposed with special crystallographic planes (surface or crystal facets) exhibit distinctive physicochemical properties because of their unique atomic arrangements, resulting in their widespread applications in the fields of catalysis, energy conversion, sensors, electrical devices and so on. Therefore, tremendous progress has been made in facet-dependent investigation of various micro-/nanocrystals over the past decades. However, a lot of beginners including undergraduate students as well as graduate students lack systematic knowledge and don't know how to identify the Miller indices of a crystallographic plane in the actual research process. So far, to the best of our knowledge, there is no specialized review article in this respect. Herein, we present a tutorial and a comprehensive review on the identification of the Miller indices of a crystallographic plane, including fundamental theory, universal methods based on different case studies, and matters needing attention. Hopefully, this tutorial review will be a beneficial theoretical and practical reference for beginners currently focusing on the controllable preparation and facet-dependent investigation of micro-/nanocrystals.
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Affiliation(s)
- Shaodong Sun
- Engineering Research Center of Conducting Materials and Composite Technology, Ministry of Education; Shaanxi Engineering Research Center of Metal-Based Heterogeneous Materials and Advanced Manufacturing Technology; Shaanxi Province Key Laboratory for Electrical Materials and Infiltration Technology; School of Materials Science and Engineering, Xi'an University of Technology, Xi'an 710048, Shaanxi, People's Republic of China.
| | - Xiaochuan Zhang
- Engineering Research Center of Conducting Materials and Composite Technology, Ministry of Education; Shaanxi Engineering Research Center of Metal-Based Heterogeneous Materials and Advanced Manufacturing Technology; Shaanxi Province Key Laboratory for Electrical Materials and Infiltration Technology; School of Materials Science and Engineering, Xi'an University of Technology, Xi'an 710048, Shaanxi, People's Republic of China.
| | - Jie Cui
- Engineering Research Center of Conducting Materials and Composite Technology, Ministry of Education; Shaanxi Engineering Research Center of Metal-Based Heterogeneous Materials and Advanced Manufacturing Technology; Shaanxi Province Key Laboratory for Electrical Materials and Infiltration Technology; School of Materials Science and Engineering, Xi'an University of Technology, Xi'an 710048, Shaanxi, People's Republic of China.
| | - Shuhua Liang
- Engineering Research Center of Conducting Materials and Composite Technology, Ministry of Education; Shaanxi Engineering Research Center of Metal-Based Heterogeneous Materials and Advanced Manufacturing Technology; Shaanxi Province Key Laboratory for Electrical Materials and Infiltration Technology; School of Materials Science and Engineering, Xi'an University of Technology, Xi'an 710048, Shaanxi, People's Republic of China.
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28
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Huang MH. Semiconductor nanocrystals possessing broadly size‐ and facet‐dependent optical properties. J CHIN CHEM SOC-TAIP 2020. [DOI: 10.1002/jccs.202000267] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Michael H. Huang
- Department of Chemistry National Tsing Hua University Hsinchu Taiwan
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29
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Chen TN, Kao JC, Zhong XY, Chan SJ, Patra AS, Lo YC, Huang MH. Facet-Specific Photocatalytic Activity Enhancement of Cu 2O Polyhedra Functionalized with 4-Ethynylanaline Resulting from Band Structure Tuning. ACS CENTRAL SCIENCE 2020; 6:984-994. [PMID: 32607445 PMCID: PMC7318064 DOI: 10.1021/acscentsci.0c00367] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Indexed: 05/16/2023]
Abstract
Cu2O rhombic dodecahedra, octahedra, and cubes were densely modified with conjugated 4-ethynylaniline (4-EA) for facet-dependent photocatalytic activity examination. Infrared spectroscopy affirms bonding of the acetylenic group of 4-EA onto the surface copper atoms. The photocatalytically inactive Cu2O cubes showed surprisingly high activity toward methyl orange photodegradation after 4-EA modification, while the already active Cu2O rhombic dodecahedra and octahedra exhibited a photocatalytic activity enhancement. Electron, hole, and radical scavenger experiments prove that the photocatalytic charge transport processes have occurred in the functionalized Cu2O cubes. Electrochemical impedance spectroscopy also indicates reduced charge transfer resistance of the functionalized Cu2O crystals. A band diagram constructed from UV-vis spectral and Mott-Schottky measurements reveals significant band energy shifts in all Cu2O samples after decorating with 4-EA. From density functional theory (DFT) calculations, a new band has emerged slightly above the valence band maximum within the band gap of Cu2O, which has been found to originate from 4-EA through band-decomposed charge density analysis. The increased charge density localized on the 4-EA molecule and the smallest electron transition energy to reach the 4-EA-generated band are factors making {100}-bound Cu2O cubes photocatalytically active. Proper molecular decoration represents a powerful approach to improving the photocatalytic efficiency of semiconductors.
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Affiliation(s)
- Tzu-Ning Chen
- Department
of Chemistry and Frontier Research Center on Fundamental and Applied
Sciences of Matters, National Tsing Hua
University, Hsinchu 30013, Taiwan
| | - Jui-Cheng Kao
- Department
of Materials Science and Engineering, National
Chiao Tung University, Hsinchu 30010, Taiwan
| | - Xin-Yan Zhong
- Department
of Materials Science and Engineering, National
Chiao Tung University, Hsinchu 30010, Taiwan
| | - Shang-Ju Chan
- Department
of Chemistry and Frontier Research Center on Fundamental and Applied
Sciences of Matters, National Tsing Hua
University, Hsinchu 30013, Taiwan
| | - Anindya S. Patra
- Department
of Chemistry and Frontier Research Center on Fundamental and Applied
Sciences of Matters, National Tsing Hua
University, Hsinchu 30013, Taiwan
| | - Yu-Chieh Lo
- Department
of Materials Science and Engineering, National
Chiao Tung University, Hsinchu 30010, Taiwan
- E-mail:
| | - Michael H. Huang
- Department
of Chemistry and Frontier Research Center on Fundamental and Applied
Sciences of Matters, National Tsing Hua
University, Hsinchu 30013, Taiwan
- E-mail:
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30
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Polyaniline stabilized Silver (I) Oxide nanocubes for sensitive and selective detection of hemoglobin in urine for hematuria evaluation. Microchem J 2020. [DOI: 10.1016/j.microc.2020.104723] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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31
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Tan CS, Zhao Y, Guo RH, Chuang WT, Chen LJ, Huang MH. Facet-Dependent Surface Trap States and Carrier Lifetimes of Silicon. NANO LETTERS 2020; 20:1952-1958. [PMID: 32023411 DOI: 10.1021/acs.nanolett.9b05237] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The facet-dependent electrical conductivity properties of silicon wafers result from significant band structure differences and variations in bond length, bond geometry, and frontier orbital electron distribution between the metal-like and semiconducting planes of silicon. To further understand the emergence of conductivity facet effects, electrochemical impedance measurements were conducted on intrinsic Si {100}, {110}, and {111} wafers. The attempt-to-escape frequency, obtained from temperature-dependent capacitance versus applied frequency curves, and other parameters derived from typical semiconductor property measurements were used to construct a diagram of the trap energy level (Et) and the amount of trap states Nt(Et). The trap states are located 0.61-0.72 eV above the silicon conduction band. Compared to {100} and {110} wafers, Si {111} wafer shows far less densities of trap states over the range of -0.2 to 2 V. Since these trap states inhibit direct electron excitation to the conduction band, the {111} wafer having much fewer trap states presents the best electrical conductivity property. Impedance data also provide facet-specific carrier lifetimes. The {111} surface gives consistently the lowest carrier lifetime, which reflects its high electrical conductivity. Lastly, ultraviolet photoelectron spectra and diffuse reflectance spectra were taken to obtain Schottky barriers between Ag and contacting Si wafers. The most conductive {111} surface presenting the largest Schottky barrier means the degrees of surface band bending used to explain facet-dependent electrical behaviors cannot be reliably attained this way.
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Affiliation(s)
- Chih-Shan Tan
- Department of Materials Science and Engineering and Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Yicheng Zhao
- Institute of Materials for Electronics and Energy Technology (i-MEET), Friedrich-Alexander-Universitat Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany
| | - Rong-Hao Guo
- National Synchrotron Radiation Research Center (NSRRC), Hsinchu 30076, Taiwan
| | - Wei-Tsung Chuang
- National Synchrotron Radiation Research Center (NSRRC), Hsinchu 30076, Taiwan
| | - Lih-Juann Chen
- Department of Materials Science and Engineering and Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Michael H Huang
- Department of Chemistry and Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsinchu 30013, Taiwan
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32
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Padilla Villavicencio M, Escobedo Morales A, Ruiz Peralta MDL, Sánchez-Cantú M, Rojas Blanco L, Chigo Anota E, Camacho García JH, Tzompantzi F. Ibuprofen Photodegradation by Ag2O and Ag/Ag2O Composites Under Simulated Visible Light Irradiation. Catal Letters 2020. [DOI: 10.1007/s10562-020-03139-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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33
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He J, Fu H, Wu P, Lin Z, Zeng Y, Jiang W. Performance promotion of Ag 2O photocatalyst by particle size and crystal surface regulation. NEW J CHEM 2020. [DOI: 10.1039/d0nj00255k] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Photocatalytic performance of Ag2O was greatly improved by adjusting the crystal plane structure and size with pyridine, which promoted the application of Ag2O to actual industrial printing and dyeing wastewater treatment systems.
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Affiliation(s)
- Jian He
- Low-Carbon Technology and Chemical Reaction Engineering Laboratory
- School of Chemical Engineering
- Sichuan University
- Chengdu
- China
| | - Hongyan Fu
- Low-Carbon Technology and Chemical Reaction Engineering Laboratory
- School of Chemical Engineering
- Sichuan University
- Chengdu
- China
| | - Pan Wu
- Low-Carbon Technology and Chemical Reaction Engineering Laboratory
- School of Chemical Engineering
- Sichuan University
- Chengdu
- China
| | - Zehao Lin
- Low-Carbon Technology and Chemical Reaction Engineering Laboratory
- School of Chemical Engineering
- Sichuan University
- Chengdu
- China
| | - Ya Zeng
- Low-Carbon Technology and Chemical Reaction Engineering Laboratory
- School of Chemical Engineering
- Sichuan University
- Chengdu
- China
| | - Wei Jiang
- Low-Carbon Technology and Chemical Reaction Engineering Laboratory
- School of Chemical Engineering
- Sichuan University
- Chengdu
- China
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34
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Madasu M, Hsieh PL, Chen YJ, Huang MH. Formation of Silver Rhombic Dodecahedra, Octahedra, and Cubes through Pseudomorphic Conversion of Ag 2O Crystals with Nitroarene Reduction Activity. ACS APPLIED MATERIALS & INTERFACES 2019; 11:38039-38045. [PMID: 31538759 DOI: 10.1021/acsami.9b12344] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Using ethanol as a co-solvent, relatively small-sized Ag2O octahedra (∼645 nm in opposite corner distance) and rhombic dodecahedra (∼540 and 655 nm in opposite face distance) were synthesized in aqueous solutions. Ag2O cubes synthesized in an aqueous solution have an edge length of ∼425 nm. Band gaps of these crystals have been obtained, revealing the presence of facet-dependent light absorption properties. The Ag2O rhombic dodecahedra, octahedra, and cubes were treated with ammonia borane in ethanol at 50 °C for just 10 min to pseudomorphically convert to Ag polyhedra of the corresponding morphologies. Transmission electron microscopy characterization confirms that the Ag cubes, octahedra, and rhombic dodecahedra are bound by the {100}, {111}, and {110} faces, respectively. The Ag rhombic dodecahedra, available for the first time, showed more superior catalytic activity toward 4-nitroaniline reduction at 50 °C than Ag octahedra and cubes, and gave 100% product yield after 1 h of reaction. This work demonstrates the value of forming Ag rhombic dodecahedra, exposing {110} surfaces that may be useful in other organic transformations.
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35
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Tsendzughul NT, Ogwu AA. Physicochemical Aspects of the Mechanisms of Rapid Antimicrobial Contact-Killing by Sputtered Silver Oxide Thin Films under Visible Light. ACS OMEGA 2019; 4:16847-16859. [PMID: 31646231 PMCID: PMC6796911 DOI: 10.1021/acsomega.9b01856] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 09/12/2019] [Indexed: 06/10/2023]
Abstract
The morphology and band gap of silver oxide thin films have been tuned by radio frequency reactive magnetron sputtering to deposit transparent, visible-light-activated photocatalytic biomaterials with excellent antimicrobial properties. X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy using the Ag 3d5/2 and Ag 3d3/2 binding energy peaks have been used to study the chemical composition of the films, and the deposition of two antimicrobial phases of silver oxide, namely, Ag2O and Ag4O4 was confirmed. The optical band gaps of the films were determined by optical spectroscopy and are in the range 2.3 eV (539.6 nm) to 3.2 eV (387.8 nm). Strong transmission of up to 80% was observed in the visible region around 650-750 nm. Silver ion release on the surfaces of the films was monitored using atomic absorption spectroscopy, and sustained silver ion release in both water and saline solution for 24 h was confirmed. Nanocrystallites of sizes between 2.45 and 31.30 nm were observed on the surfaces. The films were challenged with two Gram-positive bacteria (Staphylococcus aureus and Staphylococcus epidermidis) and two Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) during antimicrobial activity tests using killing curve analysis with 100% contact killing recorded in 25 and 5 min, respectively. The mechanism of antimicrobial efficacy is suggested to be due to silver ion release, small crystallites, and the ease of ligand replacement in the silver oxide stoichiometry, their exchange and interactions of ligands in the microbe's biological systems. Our current finding opens the door to furthering the development of visible-light-activated antimicrobial surfaces.
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Affiliation(s)
- Nathaniel T. Tsendzughul
- School
of Computing, Engineering and Physical Sciences, University of the West of Scotland, High Street, Paisley Campus, PA1 2BE Scotland, U.K.
| | - Abraham A. Ogwu
- East
Kazakhstan State Technical University, Ust-Kamenogorsk 070004, Republic of Kazakhstan
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36
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Li J, Li X, Yin Z, Wang X, Ma H, Wang L. Synergetic Effect of Facet Junction and Specific Facet Activation of ZnFe 2O 4 Nanoparticles on Photocatalytic Activity Improvement. ACS APPLIED MATERIALS & INTERFACES 2019; 11:29004-29013. [PMID: 31314495 DOI: 10.1021/acsami.9b11836] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Crystal facet engineering has been proved as a versatile approach in modulating the photocatalytic activity of semiconductors. However, the facet-dependent properties and underlying mechanisms of spinel ZnFe2O4 in photocatalysis still have rarely been explored. Herein, ZnFe2O4 nanoparticles with different {001} and {111} facets exposed were successfully synthesized via a facile hydrothermal method. Facet-dependent photocatalytic degradation performance toward gaseous toluene under visible light irradiation was observed, where truncated octahedral ZnFe2O4 (ZFO(T)) nanoparticles with both {001} and {111} facets exposed exhibited a superior performance than the others. The formed surface facet junction between {010} and {100} facets was responsible for the improved activity by separating photogenerated e-/h+ pairs efficiently to reduce their recombination rate. Photogenerated electrons and holes were demonstrated to be immigrated onto {001} and {111} facets, separately. Intriguingly, electron paramagnetic resonance trapping results indicated that both •O2- and •OH were abundantly present in the ZFO(T) sample under visible light irradiation as major reactive oxygen species involved in the photocatalytic degradation process. Additionally, further investigation revealed that {001} facets played a predominant role in activating photogenerated transient species H2O2 into •OH, beneficially boosting the intrinsic photocatalytic activity. This work has not only presented a promising strategy in regulating photocatalytic performance through the synergetic effect of facet junction and specific facet activation but also broadened the application of facet engineering with multiple effects simultaneously cooperating.
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Affiliation(s)
- Jianan Li
- State Key Laboratory of Fine Chemicals and Key Laboratory of Industrial Ecology and Environmental Engineering, School of Environmental Science & Technology , Dalian University of Technology , Dalian 116024 , China
| | - Xinyong Li
- State Key Laboratory of Fine Chemicals and Key Laboratory of Industrial Ecology and Environmental Engineering, School of Environmental Science & Technology , Dalian University of Technology , Dalian 116024 , China
- ARC Centre of Excellence for Functional Nanomaterials, School of Chemical Engineering , The University of Queensland , St. Lucia , Brisbane , Queensland 4072 , Australia
| | - Zhifan Yin
- State Key Laboratory of Fine Chemicals and Key Laboratory of Industrial Ecology and Environmental Engineering, School of Environmental Science & Technology , Dalian University of Technology , Dalian 116024 , China
| | - Xinyang Wang
- State Key Laboratory of Fine Chemicals and Key Laboratory of Industrial Ecology and Environmental Engineering, School of Environmental Science & Technology , Dalian University of Technology , Dalian 116024 , China
| | - Hangfan Ma
- State Key Laboratory of Fine Chemicals and Key Laboratory of Industrial Ecology and Environmental Engineering, School of Environmental Science & Technology , Dalian University of Technology , Dalian 116024 , China
| | - Lianzhou Wang
- ARC Centre of Excellence for Functional Nanomaterials, School of Chemical Engineering , The University of Queensland , St. Lucia , Brisbane , Queensland 4072 , Australia
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37
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Tsai CY, Liu CW, Hsi HC, Lin KS, Lin YW, Lai LC, Weng TN. Preparation of AgCl/TNTs nanocomposites for organic dyes and inorganic heavy metal removal. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:22082-22096. [PMID: 31147996 DOI: 10.1007/s11356-019-05570-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 05/24/2019] [Indexed: 06/09/2023]
Abstract
In this study, TiO2 nanotubes (TNTs) and AgCl-modified TNTs nanocomposites with multiple crystal phases were synthesized through a hydrothermal method without calcination. The resultant samples had a large Brunauer-Emmett-Teller surface area. Additionally, the Ag modification process reduced the recombination rate of electron-hole pairs in the synthesized sample and possessed more oxygen vacancy sites. The surface area of the AgCl-modified TNTs was smaller than that of non-modified TNTs sample; however, the nanocomposites exhibited outstanding photocatalytic performance and adsorption properties. AgCl compounds present on the TNTs surface effectively interacted with Hg0, improving the dye photodegradation efficiency. The Hg0 removal efficiencies of the TNTs and AgCl-modified TNTs samples were about 63% and 86%, respectively. The crystal violet (CV) and malachite green (MG) removal efficiencies of the AgCl-modified TNTs sample were around 57% and 72%, respectively. Both dyes photodecomposition efficiencies for AgCl-modified TNTs sample are higher than those of TNTs sample. The oxygen vacancy on the AgCl-modified TNTs surface was determined to be advantageous for OH- and arsenate adsorption through ligand exchange. The maximum adsorption quantity of As5+ calculated by Langmuir equation was 15.38 mg g-1 (TNTs) and 21.10 mg g-1 (AgCl-modified TNTs).
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Affiliation(s)
- Cheng-Yen Tsai
- Department of Bioenvironmental Systems Engineering, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 106, Taiwan
| | - Chen-Wuing Liu
- Department of Bioenvironmental Systems Engineering, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 106, Taiwan.
| | - Hsing-Cheng Hsi
- Graduate Institute of Environmental Engineering, National Taiwan University, No. 71, Chou-Shan Road, Taipei, 106, Taiwan
| | - Kuen-Song Lin
- Department of Chemical Engineering and Materials Science, Yuan Ze University, No. 135, Yuan-Tung Road, Chung-Li, Taoyuan City, 320, Taiwan
| | - Yi-Wen Lin
- Department of Bioenvironmental Systems Engineering, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 106, Taiwan
| | - Li-Chi Lai
- Department of Bioenvironmental Systems Engineering, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 106, Taiwan
| | - Tsung-Nan Weng
- Department of Bioenvironmental Systems Engineering, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 106, Taiwan
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38
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Huang MH. Facet-Dependent Optical Properties of Semiconductor Nanocrystals. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2019; 15:e1804726. [PMID: 30650238 DOI: 10.1002/smll.201804726] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 12/14/2018] [Indexed: 05/10/2023]
Abstract
Recent observations of facet-dependent electrical conductivity and photocatalytic activity of various semiconductor crystals are presented. Then, the discovery of facet-dependent surface plasmon resonance absorption of metal-Cu2 O core-shell nanocrystals with tunable sizes and shapes is discussed. The Cu2 O shells also exhibit a facet-specific optical absorption feature. The facet-dependent electrical conductivity, photocatalytic activity, and optical properties are related phenomena, resulting from the presence of an ultrathin surface layer with different band structures and thus varying degrees of band bending for the {100}, {110}, and {111} faces of Cu2 O to absorb light of somewhat different wavelengths. Recently, it is shown that the light absorption and photoluminescence properties of pure Cu2 O cubes, octahedra, and rhombic dodecahedra also display size and facet effects because of their tunable band gaps. A modified band diagram of Cu2 O can be constructed to incorporate these optical effects. Literature also provides examples of facet-dependent optical behaviors of semiconductor nanostructures, indicating that optical properties of nanoscale semiconductor materials are intrinsically facet-dependent. Some applications of semiconductor optical size and facet effects are considered.
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Affiliation(s)
- Michael H Huang
- Department of Chemistry and Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsinchu, 30013, Taiwan
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39
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Naresh G, Hsieh PL, Meena V, Lee SK, Chiu YH, Madasu M, Lee AT, Tsai HY, Lai TH, Hsu YJ, Lo YC, Huang MH. Facet-Dependent Photocatalytic Behaviors of ZnS-Decorated Cu 2O Polyhedra Arising from Tunable Interfacial Band Alignment. ACS APPLIED MATERIALS & INTERFACES 2019; 11:3582-3589. [PMID: 30592409 DOI: 10.1021/acsami.8b19197] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
ZnS particles were grown over Cu2O cubes, octahedra, and rhombic dodecahedra for examination of their facet-dependent photocatalytic behaviors. After ZnS growth, Cu2O cubes stay photocatalytically inactive. ZnS-decorated Cu2O octahedra show enhanced photocatalytic activity, resulting from better charge carrier separation upon photoexcitation. Surprisingly, Cu2O rhombic dodecahedra give greatly suppressed photocatalytic activity after ZnS deposition. Electron paramagnetic resonance spectra agree with these experimental observations. Time-resolved photoluminescence profiles provide charge-transfer insights. The decrease in the photocatalytic activity is attributed to an unfavorable band alignment caused by significant band bending within the Cu2O(110)/ZnS(200) plane interface. A modified Cu2O-ZnS band diagram is presented. Density functional theory calculations generating plane-specific band energy diagrams of Cu2O and ZnS match well with the experimental results, showing that charge transfer across the Cu2O(110)/ZnS(200) plane interface would not happen. This example further illustrates that the actual photocatalysis outcome for semiconductor heterojunctions cannot be assumed because interfacial charge transfer is strongly facet-dependent.
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Affiliation(s)
| | | | - Vandana Meena
- Department of Chemistry , Indian Institute of Technology Roorkee , Roorkee 247 667 , India
| | - Shih-Kuang Lee
- Department of Materials Science and Engineering , National Chiao Tung University , Hsinchu 30010 , Taiwan
| | - Yi-Hsuan Chiu
- Department of Materials Science and Engineering , National Chiao Tung University , Hsinchu 30010 , Taiwan
| | | | | | | | - Ting-Hsuan Lai
- Department of Materials Science and Engineering , National Chiao Tung University , Hsinchu 30010 , Taiwan
| | - Yung-Jung Hsu
- Department of Materials Science and Engineering , National Chiao Tung University , Hsinchu 30010 , Taiwan
| | - Yu-Chieh Lo
- Department of Materials Science and Engineering , National Chiao Tung University , Hsinchu 30010 , Taiwan
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Abstract
Ag2O/TiO2 heterojunctions were prepared by a simple method, i.e., the grinding of argentous oxide with six different titania photocatalysts. The physicochemical properties of the obtained photocatalysts were characterized by diffuse-reflectance spectroscopy (DRS), X-ray powder diffraction (XRD) and scanning transmission electron microscopy (STEM) with an energy dispersive X-ray spectroscopy (EDS). The photocatalytic activity was investigated for the oxidative decomposition of acetic acid and methanol dehydrogenation under UV/vis irradiation and for the oxidative decomposition of phenol and 2-propanol under vis irradiation. Antimicrobial properties were tested for bacteria (Escherichia coli) and fungi (Candida albicans and Penicillium chrysogenum) under UV and vis irradiation and in the dark. Enhanced activity was observed under UV/vis (with synergism for fine anatase-containing samples) and vis irradiation for almost all samples. This suggests a hindered recombination of charge carriers by p-n heterojunction or Z-scheme mechanisms under UV irradiation and photo-excited electron transfer from Ag2O to TiO2 under vis irradiation. Improved antimicrobial properties were achieved, especially under vis irradiation, probably due to electrostatic attractions between the negative surface of microorganisms and the positively charged Ag2O.
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Hsieh P, Lee A, Chen L, Huang MH. Germanium Wafers Possessing Facet‐Dependent Electrical Conductivity Properties. Angew Chem Int Ed Engl 2018; 57:16162-16165. [DOI: 10.1002/anie.201809132] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Indexed: 11/12/2022]
Affiliation(s)
- Pei‐Lun Hsieh
- Department of Materials Science and Engineering and Frontier Research Center on Fundamental and Applied Sciences of MattersNational Tsing Hua University Hsinchu 30013 Taiwan
| | - An‐Ting Lee
- Department of Chemistry and Frontier Research Center on Fundamental and Applied Sciences of MattersNational Tsing Hua University Hsinchu 30013 Taiwan
| | - Lih‐Juann Chen
- Department of Materials Science and Engineering and Frontier Research Center on Fundamental and Applied Sciences of MattersNational Tsing Hua University Hsinchu 30013 Taiwan
| | - Michael H. Huang
- Department of Chemistry and Frontier Research Center on Fundamental and Applied Sciences of MattersNational Tsing Hua University Hsinchu 30013 Taiwan
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42
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Hsieh P, Lee A, Chen L, Huang MH. Germanium Wafers Possessing Facet‐Dependent Electrical Conductivity Properties. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201809132] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Pei‐Lun Hsieh
- Department of Materials Science and Engineering and Frontier Research Center on Fundamental and Applied Sciences of MattersNational Tsing Hua University Hsinchu 30013 Taiwan
| | - An‐Ting Lee
- Department of Chemistry and Frontier Research Center on Fundamental and Applied Sciences of MattersNational Tsing Hua University Hsinchu 30013 Taiwan
| | - Lih‐Juann Chen
- Department of Materials Science and Engineering and Frontier Research Center on Fundamental and Applied Sciences of MattersNational Tsing Hua University Hsinchu 30013 Taiwan
| | - Michael H. Huang
- Department of Chemistry and Frontier Research Center on Fundamental and Applied Sciences of MattersNational Tsing Hua University Hsinchu 30013 Taiwan
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Huang MH, Naresh G, Chen HS. Facet-Dependent Electrical, Photocatalytic, and Optical Properties of Semiconductor Crystals and Their Implications for Applications. ACS APPLIED MATERIALS & INTERFACES 2018; 10:4-15. [PMID: 29227621 DOI: 10.1021/acsami.7b15828] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Recent studies on the electrical conductivity and photocatalytic activity properties of semiconductor nanocrystals such as Cu2O, Ag2O, TiO2, PbS, and Ag3PO4 exposing well-defined surfaces have revealed strong facet effects. For example, the electrical conductivity of Cu2O crystals can vary from highly conductive to nonconductive, and they can be highly photocatalytically active or inactive depending on the exposed faces. The crystal surfaces can even tune their light absorption wavelengths. Our understanding is that the emergence of these unusual phenomena can be explained in terms of the presence of an ultrathin surface layer having different band structures and degrees of band bending for different surfaces, which affects charge transport and photons into and out of the crystals. This review uses primarily results from our research on this frontier area of semiconductor properties to illustrate the existence of semiconductor facet effects. A simple adjustment to normal semiconductor band diagram allows good understanding of the observed phenomena. Recognizing that facet-dependent behaviors are intrinsic semiconductor properties, we should pay attention to their influence in the explanation of the measured photocatalytic properties, and consider ways to enhance photocatalytic efficiency or design electrical components utilizing the facet effects. There should be many opportunities to advance applications of semiconductor nanocrystals and nanostructures with continued research on the facet-dependent properties of various semiconductor materials.
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Affiliation(s)
- Michael H Huang
- Department of Chemistry, National Tsing Hua University , Hsinchu 30013, Taiwan
| | - Gollapally Naresh
- Department of Chemistry, National Tsing Hua University , Hsinchu 30013, Taiwan
| | - Hsiang-Sheng Chen
- Department of Chemistry, National Tsing Hua University , Hsinchu 30013, Taiwan
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44
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Feng F, Chen M, Wu JH. Morphology-selective synthesis of Cu(NO3)2·2.5H2O micro/nanostructures achieved by rational manipulation of nucleation pathways and their morphology-preserved conversion to CuO porous micro/nanostructures. CrystEngComm 2018. [DOI: 10.1039/c8ce00049b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A special Cu(NO3)2 thin solution layer was built on highly hydrophilic mica surfaces and subjected to rapid evaporation. Controlling the evaporation time can intentionally manipulate the supersaturation.
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Affiliation(s)
- Feng Feng
- College of Chemistry
- Chemical Engineering and Materials Science
- Soochow University
- Suzhou
- 215123 China
| | - Muzi Chen
- Testing & Analysis Center
- Soochow University
- Suzhou
- 215123 China
| | - Ji Hong Wu
- College of Chemistry
- Chemical Engineering and Materials Science
- Soochow University
- Suzhou
- 215123 China
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45
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Firestein KL, Leybo DV, Steinman AE, Kovalskii AM, Matveev AT, Manakhov AM, Sukhorukova IV, Slukin PV, Fursova NK, Ignatov SG, Golberg DV, Shtansky DV. BN/Ag hybrid nanomaterials with petal-like surfaces as catalysts and antibacterial agents. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2018; 9:250-261. [PMID: 29441270 PMCID: PMC5789442 DOI: 10.3762/bjnano.9.27] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 12/27/2017] [Indexed: 05/08/2023]
Abstract
BN/Ag hybrid nanomaterials (HNMs) and their possible applications as novel active catalysts and antibacterial agents are investigated. BN/Ag nanoparticle (NP) hybrids were fabricated using two methods: (i) chemical vapour deposition (CVD) of BN NPs in the presence of Ag vapours, and (ii) ultraviolet (UV) decomposition of AgNO3 in a suspension of BN NPs. The hybrid microstructures were studied by high-resolution transmission electron microscopy (HRTEM), high-angular dark field scanning TEM imaging paired with energy dispersion X-ray (EDX) mapping, X-ray photoelectron spectroscopy (XPS), and infrared spectroscopy (FTIR). They were also characterized in terms of thermal stability, Ag+ ion release, catalytic and antibacterial activities. The materials synthesized via UV decomposition of AgNO3 demonstrated a much better catalytic activity in comparison to those prepared using the CVD method. The best catalytic characteristics (100% methanol conversion at 350 °C) were achieved using the UV BN/Ag HNMs without preliminary annealing at 600 °C in an oxidizing atmosphere. Both types of the BN/Ag HNMs possess a profound antibacterial effect against Escherichia coli K-261 bacteria.
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Affiliation(s)
- Konstantin L Firestein
- National University of Science and Technology “MISIS”, Leninsky prospect 4, Moscow, 119049, Russian Federation
- School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology (QUT), 2nd George st., Brisbane, QLD 4000, Australia
| | - Denis V Leybo
- National University of Science and Technology “MISIS”, Leninsky prospect 4, Moscow, 119049, Russian Federation
| | - Alexander E Steinman
- National University of Science and Technology “MISIS”, Leninsky prospect 4, Moscow, 119049, Russian Federation
| | - Andrey M Kovalskii
- National University of Science and Technology “MISIS”, Leninsky prospect 4, Moscow, 119049, Russian Federation
| | - Andrei T Matveev
- National University of Science and Technology “MISIS”, Leninsky prospect 4, Moscow, 119049, Russian Federation
| | - Anton M Manakhov
- National University of Science and Technology “MISIS”, Leninsky prospect 4, Moscow, 119049, Russian Federation
| | - Irina V Sukhorukova
- National University of Science and Technology “MISIS”, Leninsky prospect 4, Moscow, 119049, Russian Federation
| | - Pavel V Slukin
- State Research Center for Applied Microbiology and Biotechnology, Obolensk, Moscow Region 142279, Russian Federation
| | - Nadezda K Fursova
- State Research Center for Applied Microbiology and Biotechnology, Obolensk, Moscow Region 142279, Russian Federation
| | - Sergey G Ignatov
- State Research Center for Applied Microbiology and Biotechnology, Obolensk, Moscow Region 142279, Russian Federation
- Moscow State University, Department of Geocryology, Moscow 119992, Russian Federation
| | - Dmitri V Golberg
- School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology (QUT), 2nd George st., Brisbane, QLD 4000, Australia
- World Premier International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Namiki 1, Ibaraki 3050044, Japan
| | - Dmitry V Shtansky
- National University of Science and Technology “MISIS”, Leninsky prospect 4, Moscow, 119049, Russian Federation
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46
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Hsieh MS, Su HJ, Hsieh PL, Chiang YW, Huang MH. Synthesis of Ag 3PO 4 Crystals with Tunable Shapes for Facet-Dependent Optical Property, Photocatalytic Activity, and Electrical Conductivity Examinations. ACS APPLIED MATERIALS & INTERFACES 2017; 9:39086-39093. [PMID: 29043767 DOI: 10.1021/acsami.7b13941] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
This work has developed conditions for the synthesis of Ag3PO4 cubes, rhombic dodecahedra, {100}-truncated rhombic dodecahedra, tetrahedra, and tetrapods by tuning the amount of NH4NO3, NaOH, AgNO3, and K2HPO4 solutions added. Use of a minimal amount of AgNO3 solution can form much smaller rhombic dodecahedra and tetrahedra. Submicrometer-sized Ag3PO4 cubes and rhombic dodecahedra with sizes larger than 300 nm do not exhibit the optical size effect, but ∼290 nm rhombic dodecahedra show a smaller band gap value than larger cubes, and tetrahedra show the most blue-shifted absorption edge. The optical facet effect is present in Ag3PO4 crystals. Ag3PO4 cubes are more photocatalytically active than rhombic dodecahedra toward photodegradation of methyl orange, but tetrahedra are inactive, showing clear presence of photocatalytic facet effects. Electron paramagnetic resonance results confirm much higher production of hydroxyl radicals from photoirradiated Ag3PO4 cubes than from rhombic dodecahedra, while tetrahedra yield essentially no radicals. A modified band diagram showing different degrees of band edge bending can explain these observations. All these Ag3PO4 crystals show poor electrical conductivity properties, but the {110} faces are slightly more conductive than the {100} faces. As a result, current rectifying I-V curves have been obtained, demonstrating that facet-dependent electrical properties are broadly observable in many semiconductor materials. This work reveals again that facet-dependent optical, photocatalytic, and electrical conductivity properties are intrinsic semiconductor properties.
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Affiliation(s)
- Meng-Shan Hsieh
- Department of Chemistry, ‡Interdisciplinary Program of Sciences, and §Department of Materials Science and Engineering, National Tsing Hua University , Hsinchu 30013, Taiwan
| | - Huang-Jen Su
- Department of Chemistry, ‡Interdisciplinary Program of Sciences, and §Department of Materials Science and Engineering, National Tsing Hua University , Hsinchu 30013, Taiwan
| | - Pei-Lun Hsieh
- Department of Chemistry, ‡Interdisciplinary Program of Sciences, and §Department of Materials Science and Engineering, National Tsing Hua University , Hsinchu 30013, Taiwan
| | - Yun-Wei Chiang
- Department of Chemistry, ‡Interdisciplinary Program of Sciences, and §Department of Materials Science and Engineering, National Tsing Hua University , Hsinchu 30013, Taiwan
| | - Michael H Huang
- Department of Chemistry, ‡Interdisciplinary Program of Sciences, and §Department of Materials Science and Engineering, National Tsing Hua University , Hsinchu 30013, Taiwan
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47
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Tan CS, Huang MH. Metal-like Band Structures of Ultrathin Si {111} and {112} Surface Layers Revealed through Density Functional Theory Calculations. Chemistry 2017; 23:11866-11871. [DOI: 10.1002/chem.201701886] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Indexed: 11/12/2022]
Affiliation(s)
- Chih-Shan Tan
- Department of Chemistry; National Tsing Hua University; Hsinchu 30013 Taiwan
| | - Michael H. Huang
- Department of Chemistry; National Tsing Hua University; Hsinchu 30013 Taiwan
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48
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Tan CS, Chen YJ, Hsia CF, Huang MH. Facet-Dependent Electrical Conductivity Properties of Silver Oxide Crystals. Chem Asian J 2017; 12:293-297. [DOI: 10.1002/asia.201601520] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2016] [Indexed: 11/07/2022]
Affiliation(s)
- Chih-Shan Tan
- Department of Chemistry; National Tsing Hua University; Hsinchu 30013 Taiwan
| | - Ying-Jui Chen
- Department of Chemistry; National Tsing Hua University; Hsinchu 30013 Taiwan
| | - Chi-Fu Hsia
- Department of Chemistry; National Tsing Hua University; Hsinchu 30013 Taiwan
| | - Michael H. Huang
- Department of Chemistry; National Tsing Hua University; Hsinchu 30013 Taiwan
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