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Sudrajat H, Wella SA, Phanthuwongpakdee J, Lisovytskiy D, Sobczak K, Colmenares JC. Atomistic understanding of enhanced selectivity in photocatalytic oxidation of benzyl alcohol to benzaldehyde using graphitic carbon nitride loaded with single copper atoms. NANOSCALE 2024; 16:14813-14830. [PMID: 39034643 DOI: 10.1039/d4nr01610f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/23/2024]
Abstract
The loading of graphitic carbon nitride (gCN) with transition metals has received significant attention for efficient light-driven catalysis. However, the contribution of the loaded metals to enhanced performance remains unclear. In this study, Cu is loaded onto gCN to understand how photocatalytic activity is regulated by the loaded metals. Loading gCN with 3 wt% of Cu increases the electron population by 8.1 and 4.6 times under UV (λ < 370 nm) and visible light (390 < λ < 740 nm), respectively. This sample shows nearly 100% selectivity for oxidizing benzyl alcohol to benzaldehyde and a high yield-to-power ratio, reaching 0.35 mmol g-1 h-1 W-1. The loaded Cu species exist as single atoms with a +1-oxidation state. Each Cu+ cation is coordinated to two (at 3 wt% Cu) or four (at 6 wt% Cu) N atoms within the cavity of the gCN framework. Doubling the Cu loading results in a smaller electron population and coordinatively more saturated Cu+ cations, making it catalytically less reactive. Ab initio molecular dynamics simulations show that Cu+ cations produce filled mid-gap states above the valence band, which function as hole traps and hence oxidation centers. The Cu+ cation and the neighboring N atoms are electron-depletion and electron-accumulation sites due to Cu → N electron transfer, making it highly reactive for oxidative transformations via the hole transfer pathway. The role of Cu as a hole-transfer site updates the received understanding that surface-loaded Cu serves as an electron-accumulation site. A strong correlation is observed between the electron population at steady-state and the product yield, indicating that it could serve as a promising performance indicator for the design of future photocatalysts.
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Affiliation(s)
- Hanggara Sudrajat
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
- Research Center for Quantum Physics, National Research and Innovation Agency (BRIN), South Tangerang 15314, Indonesia
- Collaboration Research Center for Advanced Energy Materials, BRIN - Institut Teknologi Bandung, Bandung 40132, Indonesia
| | - Sasfan Arman Wella
- Research Center for Quantum Physics, National Research and Innovation Agency (BRIN), South Tangerang 15314, Indonesia
- Collaboration Research Center for Advanced Energy Materials, BRIN - Institut Teknologi Bandung, Bandung 40132, Indonesia
| | | | - Dmytro Lisovytskiy
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
| | - Kamil Sobczak
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, 02-089 Warsaw, Poland
| | - Juan Carlos Colmenares
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
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2
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Zeng D, Li Y. Precisely Assembling a CoO Cocatalyst onto Tb 4O 7/CN and Pt-Tb 4O 7/CN for Promoting Photocatalytic Overall Water Splitting. Inorg Chem 2024; 63:8397-8407. [PMID: 38652804 DOI: 10.1021/acs.inorgchem.4c00849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
Photocatalytic overall water splitting (POWS) is a promising approach for solar-to-hydrogen conversion. For achieving this target, it is urgent to develop efficient photocatalysts. Constructing a heterojunction and loading a cocatalyst are two effective strategies for enhancing POWS. However, how to achieve the cooperation of loading the cocatalyst site with the charge separation of a heterojunction remains a huge challenge. Herein, we present an ingenious method: precisely assembling a H2O2-producing cocatalyst CoO on Tb4O7/CN. Assembling CoO on CN of Tb4O7/CN improves the photoinduced electron-hole pair separation and promotes the POWS performance. Inversely, engineering CoO on Tb4O7 leads to production of Co, deactivating POWS performance with a H2-evolution rate 5.2 times lower than that of Tb4O7/CN. Furthermore, we precisely assemble CoO on the CN section of Pt-oriented Pt-Tb4O7/CN. The bioriented CoO and Pt cooperatively promote photogenerated carrier separation. Consequently, the prepared Pt-Tb4O7/CN-CoO exhibits spectacularly high POWS activity. The H2-evolution rate reaches 450 μmol h-1 g-1, which is about 9.4 times higher than that of the initial Tb4O7/CN. The apparent quantum yield (AQY) for H2 evolution at 420 nm reaches 14.1%, surpassing those of most reported CN-based photocatalysts. This work offers an approach to precisely load cocatalysts on heterojunctions. These findings provide insights for designing cocatalyst-decorated heterojunctions for POWS.
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Affiliation(s)
- Dedong Zeng
- School of Chemistry and Chemical Engineering, Key Laboratory of Jiangxi Province for Environment and Energy Catalysis, Nanchang University, Nanchang 330031, China
| | - Yuexiang Li
- School of Chemistry and Chemical Engineering, Key Laboratory of Jiangxi Province for Environment and Energy Catalysis, Nanchang University, Nanchang 330031, China
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3
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Ma L, Guan R, Kang W, Sun Z, Li H, Li Q, Shen Q, Chen C, Liu X, Jia H, Xue J. Preparation of highly dispersed Ni single-atom doped ultrathin g-C 3N 4 nanosheets by metal vapor exfoliation for efficient photocatalytic CO 2 reduction. J Colloid Interface Sci 2024; 660:381-392. [PMID: 38244504 DOI: 10.1016/j.jcis.2024.01.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 12/27/2023] [Accepted: 01/04/2024] [Indexed: 01/22/2024]
Abstract
Single-atom photocatalysts can modulate the utilization of photons and facilitate the migration of photogenerated carriers. However, the preparation of single-atom uniformly doped photocatalysts is still a challenging topic. Herein, we propose the preparation of Ni single-atom doped g-C3N4 photocatalysts by metal vapor exfoliation. The Ni vapor produced by calcining nickel foam at high temperature accumulates in between g-C3N4 layers and poses a certain vapor pressure to destroy the interlayer van der Waals forces of g-C3N4. Individual metal atoms are doped into the structure while exfoliating g-C3N4 into nanosheets by metal vapor. Upon optimization of Ni content, the Ni single atom doped g-C3N4 nanosheets with 2.81 wt% Ni exhibits the highest CO2 reduction performance in the absence of sacrificial agents. The generation rates of CO and CH4 are 19.85 and 1.73 μmol g-1h-1, respectively. The improved photocatalytic performance is attributed to the anchoring Ni of single atoms on g-C3N4 nanosheets, which increases both carrier separation efficiency and reaction sites. This work provides insight into the design of photocatalysts with highly dispersed single-atom.
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Affiliation(s)
- Lin Ma
- Key Laboratory of Interface Science and Engineering in Advanced Materials (Taiyuan University of Technology), Ministry of Education, Taiyuan 030024, PR China; College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, PR China
| | - Rongfeng Guan
- Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province, Yancheng Institute of Technology, Yancheng 224051, PR China
| | - Wenxiang Kang
- Key Laboratory of Interface Science and Engineering in Advanced Materials (Taiyuan University of Technology), Ministry of Education, Taiyuan 030024, PR China; College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, PR China
| | - Zhe Sun
- Key Laboratory of Interface Science and Engineering in Advanced Materials (Taiyuan University of Technology), Ministry of Education, Taiyuan 030024, PR China; College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, PR China
| | - Huimin Li
- Key Laboratory of Interface Science and Engineering in Advanced Materials (Taiyuan University of Technology), Ministry of Education, Taiyuan 030024, PR China; College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, PR China
| | - Qiurong Li
- Key Laboratory of Interface Science and Engineering in Advanced Materials (Taiyuan University of Technology), Ministry of Education, Taiyuan 030024, PR China; College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, PR China
| | - Qianqian Shen
- Key Laboratory of Interface Science and Engineering in Advanced Materials (Taiyuan University of Technology), Ministry of Education, Taiyuan 030024, PR China; College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, PR China
| | - Chaoqiu Chen
- State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, PR China
| | - Xuguang Liu
- Key Laboratory of Interface Science and Engineering in Advanced Materials (Taiyuan University of Technology), Ministry of Education, Taiyuan 030024, PR China; College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, PR China
| | - Husheng Jia
- Key Laboratory of Interface Science and Engineering in Advanced Materials (Taiyuan University of Technology), Ministry of Education, Taiyuan 030024, PR China; College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, PR China
| | - Jinbo Xue
- Key Laboratory of Interface Science and Engineering in Advanced Materials (Taiyuan University of Technology), Ministry of Education, Taiyuan 030024, PR China; College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, PR China.
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4
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Wang J, Zhao C, Yuan S, Li X, Zhang J, Hu X, Lin H, Wu Y, He Y. One-step fabrication of Cu-doped Bi 2MoO 6 microflower for enhancing performance in photocatalytic nitrogen fixation. J Colloid Interface Sci 2023; 638:427-438. [PMID: 36758255 DOI: 10.1016/j.jcis.2023.02.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 01/27/2023] [Accepted: 02/01/2023] [Indexed: 02/05/2023]
Abstract
This study enhances the photocatalytic N2 immobilization performance of Bi2MoO6 through Cu doping. Cu-doped Bi2MoO6 was synthesized via a simple solvothermal method. Various characterizations were implemented to examine the influence of Cu doping on the properties of Bi2MoO6. Results indicated that the doped Cu element had a valence state of + 2 and substituted the position of Bi3+. Cu doping exerted minimal effect on the morphology of Bi2MoO6 but largely influenced the energy band structure. The band gap was slightly narrowed, and the conduction band was raised, such that Cu-doped Bi2MoO6 could generate more electrons with stronger reducibility. Moreover, importantly, Cu doping reduced work function and improved charge separation efficiency, which was considered the major cause of enhanced photoactivity. In addition, the Cu-Bi2MoO6 catalyst exhibited higher capability in the adsorption and activation of N2. Under the combined effects of the aforementioned changes, Cu-Bi2MoO6 demonstrated considerably higher photocatalytic efficiency than Bi2MoO6. The optimized NH3 generation rate reached 302 μmol/L g-1h-1 and 157 μmol/L g-1h-1 under simulated solar light and visible light, respectively, both achieving about 2.2 times higher than that of Bi2MoO6. This work provides a successful example of improving photocatalytic N2 fixation, and it may show some light on the design and preparation of heteroatom-doped semiconductor photocatalysts for N2-to-NH3 conversion.
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Affiliation(s)
- Junfeng Wang
- Department of Materials Science and Engineering, Zhejiang Normal University, Yingbin Road 688, Jinhua 321004, China
| | - Chunran Zhao
- Department of Materials Science and Engineering, Zhejiang Normal University, Yingbin Road 688, Jinhua 321004, China
| | - Shude Yuan
- Department of Materials Science and Engineering, Zhejiang Normal University, Yingbin Road 688, Jinhua 321004, China
| | - Xiaojing Li
- Department of Materials Science and Engineering, Zhejiang Normal University, Yingbin Road 688, Jinhua 321004, China
| | - Jiayu Zhang
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Institute of Physical Chemistry, Zhejiang Normal University, Yingbin Road 688, Jinhua 321004, China
| | - Xin Hu
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Institute of Physical Chemistry, Zhejiang Normal University, Yingbin Road 688, Jinhua 321004, China
| | - Hongjun Lin
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua 321004, China
| | - Ying Wu
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Institute of Physical Chemistry, Zhejiang Normal University, Yingbin Road 688, Jinhua 321004, China.
| | - Yiming He
- Department of Materials Science and Engineering, Zhejiang Normal University, Yingbin Road 688, Jinhua 321004, China; Key Laboratory of Solid State Optoelectronic Devices of Zhejiang province, Zhejiang Normal University, Yingbin Road 688, Jinhua 321004, China.
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5
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Kao CC, Ye C, Hao J, Shan J, Li H, Qiao SZ. Suppressing Hydrogen Evolution via Anticatalytic Interfaces toward Highly Efficient Aqueous Zn-Ion Batteries. ACS NANO 2023; 17:3948-3957. [PMID: 36744842 DOI: 10.1021/acsnano.2c12587] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Aqueous Zn-ion batteries hold practical promise for large-scale energy storage because of the safety and affordability of aqueous-based electrolytes; in addition, the manufacturing process is significantly simplified by direct employment of Zn metal as an anode. However, hydrogen evolution due to near-surface water dissociation has hindered large-scale applications of them. Here, we report the suppression of the hydrogen evolution reaction via a CuN3-coordinated graphitic carbonitride (CuN3-C3N4) anticatalytic interface to achieve highly efficient aqueous Zn-ion batteries. Based on in situ gas chromatography and in situ synchrotron-based X-ray diffraction spectroscopy, we demonstrated that the hydrogen evolution reaction triggers the Zn4SO4(OH)6·xH2O formation. A combination of in situ infrared spectroscopy and density functional theory simulations has proved to stabilize near-surface H3O+ species and regulate adsorption of H* intermediates by an anticatalytic interface for hydrogen evolution reaction suppression. Consequently, the anticatalytic interface greatly improves the Coulombic efficiency of Zn plating/stripping to ∼99.7% for 5500 cycles and the cycling reversibility to over 1300 h at 1 mA cm-2 and 1 mAh cm-2. With an anticatalytic interface, the full cell shows an excellent Coulombic efficiency of 98.3% over 400 cycles at 1C. These findings provide strategic insight for targeted designing of highly efficient aqueous Zn-ion batteries.
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Affiliation(s)
- Chun-Chuan Kao
- School of Chemical Engineering and Advanced Materials, The University of Adelaide, Adelaide, SA5005, Australia
| | - Chao Ye
- School of Chemical Engineering and Advanced Materials, The University of Adelaide, Adelaide, SA5005, Australia
| | - Junnan Hao
- School of Chemical Engineering and Advanced Materials, The University of Adelaide, Adelaide, SA5005, Australia
| | - Jieqiong Shan
- School of Chemical Engineering and Advanced Materials, The University of Adelaide, Adelaide, SA5005, Australia
| | - Huan Li
- School of Chemical Engineering and Advanced Materials, The University of Adelaide, Adelaide, SA5005, Australia
| | - Shi-Zhang Qiao
- School of Chemical Engineering and Advanced Materials, The University of Adelaide, Adelaide, SA5005, Australia
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6
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Eid K, Sliem MH, Al-Ejji M, Abdullah AM, Harfouche M, Varma RS. Hierarchical Porous Carbon Nitride-Crumpled Nanosheet-Embedded Copper Single Atoms: An Efficient Catalyst for Carbon Monoxide Oxidation. ACS APPLIED MATERIALS & INTERFACES 2022; 14:40749-40760. [PMID: 36037411 DOI: 10.1021/acsami.2c06782] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Rational design of metal single-site embedded porous graphitic carbon nitride (P-g-C3N4) nanostructures exploiting maximum atom utilization is warranted to enhance the thermal CO oxidation (COOx) reaction. Herein, a facile, green, one-pot, and template-free approach is developed to fabricate the hierarchical porous P-g-C3N4-crumpled ultrathin nanosheets atomically doped with copper single atoms (Cu-P-g-C3N4). Mechanistically, the quick protonation of melamine and pyridine under acidic conditions induces deamination to form melem, which is polycondensed under heating. The interconnected pores, high surface area (240 m2g-1), and maximized exposed isolated Cu atomic active sites (1.8 wt %) coordinated with nitrogen atom P-g-C3N4 are the salient features of Cu- P-g-C3N4 that endowed complete conversion to CO2 at 184 °C. In contrast, P-g-C3N4 only converted 3.8% of CO even at 350 °C, implying the electronic effect of Cu single atoms. The abundant Cu-nitrogen moieties can drastically weaken the binding affinity of the CO-oxidation (COOx) intermediates and products, thus accelerating the reaction kinetics at a low temperature. This study may promote the fabrication of P-g-C3N4 doped with various single atoms for the oxidation of CO.
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Affiliation(s)
- Kamel Eid
- Gas Processing Center, College of Engineering, Qatar University, Doha 2713, Qatar
| | - Mostafa H Sliem
- Center for Advanced Materials, Qatar University, Doha 2713, Qatar
| | - Maryam Al-Ejji
- Center for Advanced Materials, Qatar University, Doha 2713, Qatar
| | | | - Messaoud Harfouche
- SESAME Synchrotron, King Hussein Bin Talal St / Box 7, Allan 19252, Jordan
| | - Rajender S Varma
- Regional Centre of Advanced Technologies and Materials, Czech Advanced Technology and Research Institute, Palacky University, Slechtitelu 27, Olomouc 783 71, Czech Republic
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7
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Capobianco MD, Younan SM, Tayvah U, Pattengale B, Neu J, Gu J, Brudvig GW. Terahertz Conductivity of Semiconducting 2H and Metallic 1T Phases of Molybdenum Disulfide. J Phys Chem Lett 2022; 13:8319-8326. [PMID: 36040312 DOI: 10.1021/acs.jpclett.2c02283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Molybdenum disulfide (MoS2) has been extensively studied in its commonly occurring semiconducting 2H phase. Recent synthetic advances have enabled the bulk synthesis of the catalytically promising metallic 1T phase. However, the conductivity of bulk 1T-MoS2 has not been well characterized to ascertain the carrier transport properties. Terahertz (THz) spectroscopy is an ideal technique for obtaining this crucial information because it is a noncontact method of measuring the conductivity of emerging materials with ultrafast time resolution. This work applies THz spectroscopy to bulk 2H-MoS2 and 1T-MoS2, representing the first application of the technique on the 1T phase, with measurements confirming the semiconducting character of 2H-MoS2 and the metallic character of 1T-MoS2. This study provides new insight into the metallic nature of bulk 1T-MoS2 and a direct comparison to the semiconducting 2H phase that, together with physical characterization to obtain material parameters, are important for optimizing applications in catalysis devices and beyond.
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Affiliation(s)
- Matt D Capobianco
- Department of Chemistry and Yale Energy Sciences Institute, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Sabrina M Younan
- Department of Chemistry and Biochemistry, San Diego State University, San Diego, California 92182-1030, United States
| | - Uriel Tayvah
- Department of Chemistry and Yale Energy Sciences Institute, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Brian Pattengale
- Department of Chemistry and Yale Energy Sciences Institute, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Jens Neu
- Department of Chemistry and Yale Energy Sciences Institute, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Jing Gu
- Department of Chemistry and Biochemistry, San Diego State University, San Diego, California 92182-1030, United States
| | - Gary W Brudvig
- Department of Chemistry and Yale Energy Sciences Institute, Yale University, New Haven, Connecticut 06520-8107, United States
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8
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Han S, Qiu T, Xiong C, Li X, Guo L. Tunable Nitrogen Defects on Graphitic Carbon Nitride toward the Visible-Light-Induced Reversible-Deactivation Radical Polymerization. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c01099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Shiwei Han
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, PR China
| | - Teng Qiu
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, PR China
- Key Laboratory of Carbon Fiber and Functional Polymers Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, People’s Republic of China
| | - Chongwen Xiong
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, PR China
| | - Xiaoyu Li
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, PR China
- Key Laboratory of Carbon Fiber and Functional Polymers Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, People’s Republic of China
| | - Longhai Guo
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, PR China
- Key Laboratory of Carbon Fiber and Functional Polymers Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, People’s Republic of China
- Beijing Engineering Research Center of Synthesis and Application of Waterborne Polymer, Beijing University of Chemical Technology, Beijing 100029, PR China
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9
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Wang G, Huang R, Zhang J, Mao J, Wang D, Li Y. Synergistic Modulation of the Separation of Photo-Generated Carriers via Engineering of Dual Atomic Sites for Promoting Photocatalytic Performance. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2105904. [PMID: 34664332 DOI: 10.1002/adma.202105904] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 09/15/2021] [Indexed: 06/13/2023]
Abstract
The separation efficiency of photo-generated carriers is still a great challenge that restricts the practical application of photocatalytic technology. The design of spatial separation path for photo-generated carriers at atomic level provides an innovative approach to address this challenge. Herein, a facile dual atomic sites strategy, consisting of Cu-N4 and C-S-C active moieties decorated on polymeric carbon nitride (Cu SAs/p-CNS) is reported to simultaneously achieve the highly efficient separation of photo-generated electrons and holes for boosting photocatalytic performance. As a proof of concept, the Cu SAs/p-CNS is successfully applied to the photo-oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-diformylfuran (DFF), which exhibits 77.1% HMF conversion and 85.6% DFF selectivity under visible light irradiation. The activity is considerably higher than that of bulk p-CN, S doped p-CN, and p-CN supported Cu single atom catalysts. Theoretical calculations and experimental results suggest that, during photocatalytic reaction, the isolated Cu-N4 sites directly capture photo-generated electrons, while the surrounding S atoms bear photo-generated holes, which synergistically facilitates the separation of photo-generated carriers and thus results in enhanced photocatalytic activity. This study provides a new perspective for the rational design of high performance photocatalysts at atomic level.
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Affiliation(s)
- Gang Wang
- Key Laboratory of Functional Molecular Solids, Ministry of Education, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, 241002, China
| | - Rong Huang
- Key Laboratory of Functional Molecular Solids, Ministry of Education, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, 241002, China
| | - Jiangwei Zhang
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| | - Junjie Mao
- Key Laboratory of Functional Molecular Solids, Ministry of Education, College of Chemistry and Materials Science, Anhui Normal University, Wuhu, 241002, China
| | - Dingsheng Wang
- Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yadong Li
- Department of Chemistry, Tsinghua University, Beijing, 100084, China
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10
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Hwang D, Schlenker CW. Photochemistry of carbon nitrides and heptazine derivatives. Chem Commun (Camb) 2021; 57:9330-9353. [PMID: 34528956 DOI: 10.1039/d1cc02745j] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We explore the photochemistry of polymeric carbon nitride (C3N4), an archetypal organic photocatalyst, and derivatives of its structural monomer unit, heptazine (Hz). Through spectroscopic studies and computational analysis, we have observed that Hz derivatives can engage in non-innocent hydrogen bonding interactions with hydroxylic species. The photochemistry of these complexes is influenced by intermolecular nπ*/ππ* mixing of non-bonding orbitals of each component and the relative energy of intermolecular charge-transfer (CT) states. Coupling of the former to the latter appears to facilitate proton-coupled electron transfer (PCET), resulting in biradical products. We have also observed that Hz derivatives exhibit an extremely rare inverted singlet/triplet energy splitting (ΔEST). In violation of Hund's multiplicity rules, the lowest energy singlet (S1) is stabilized relative to the lowest triplet (T1) electronic excited state. Exploiting this unique inverted ΔEST character has obvious implications for transformational discoveries in solid-state OLED lighting and photovoltaics. Harnessing this inverted ΔEST, paired with light-driven intermolecular PCET reactions, may enable molecular transformations relevant for applications ranging from solar energy storage to new classes of non-triplet photoredox catalysts for pharmaceutical development. To this end, we have explored the possibility of optically controlling the photochemistry of Hz derivatives using ultrafast pump-push-probe spectroscopy. In this case, the excited state branching ratios among locally excited states of the chromophore and the reactive intermolecular CT state can be manipulated with an appropriate secondary "push" excitation pulse. These results indicate that we can predictively redirect chemical reactivity with light in this system, which is an avidly sought achievement in the field of photochemistry. Looking forward, we anticipate future opportunities for controlling heptazine photochemistry, including manipulating PCET reactivity with a diverse array of substrates and optically delivering reducing equivalents with, for example, water as a partial source of electrons and protons. Furthermore, we wholly expect that, over the next decade, materials such as Hz derivatives, that exhibit inverted ΔEST character, will spawn a significant new research effort in the field of thin-film optoelectronics, where controlling recombination via triplet excitonic states can play a critical role in determining device performance.
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Affiliation(s)
- Doyk Hwang
- Department of Chemistry, University of Washington, Seattle, Washington 98195, USA
| | - Cody W Schlenker
- Department of Chemistry, University of Washington, Seattle, Washington 98195, USA.,Molecular Engineering & Sciences Institute, University of Washington, Seattle, Washington 98195-1652, USA.,Clean Energy Institute, University of Washington, Seattle, Washington 98195-1653, USA.
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11
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Yan K, Mu C, Meng L, Fei Z, Dyson PJ. Recent advances in graphite carbon nitride-based nanocomposites: structure, antibacterial properties and synergies. NANOSCALE ADVANCES 2021; 3:3708-3729. [PMID: 36133016 PMCID: PMC9419292 DOI: 10.1039/d1na00257k] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 05/27/2021] [Indexed: 05/04/2023]
Abstract
Bacterial infections and transmission threaten human health and well-being. Graphite carbon nitride (g-C3N4), a promising photocatalytic antibacterial nanomaterial, has attracted increasing attention to combat bacterial transmission, due to the outstanding stability, high efficiency and environmental sustainability of this material. However, the antibacterial efficiency of g-C3N4 is affected by several factors, including its specific surface area, rapid electron/hole recombination processes and optical absorption properties. To improve the efficiency of the antibacterial properties of g-C3N4 and extend its range of applications, various nanocomposites have been prepared and evaluated. In this review, the advances in amplifying the photocatalytic antibacterial efficiency of g-C3N4-based nanocomposites is discussed, including different topologies, noble metal decoration, non-noble metal doping and heterojunction construction. The enhancement mechanisms and synergistic effects in g-C3N4-based nanocomposites are highlighted. The remaining challenges and future perspectives of antibacterial g-C3N4-based nanocomposites are also discussed.
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Affiliation(s)
- Kai Yan
- School of Chemistry, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Xi'an Jiaotong University Xi'an 710049 P. R. China
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science and Technology Xi'an 710021 China
| | - Chenglong Mu
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science and Technology Xi'an 710021 China
| | - Lingjie Meng
- School of Chemistry, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, Xi'an Key Laboratory of Sustainable Energy Material Chemistry, Xi'an Jiaotong University Xi'an 710049 P. R. China
- Instrumental Analysis Center, Xi'an Jiaotong University Xi'an 710049 P. R. China
| | - Zhaofu Fei
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL) CH-1015 Lausanne Switzerland
| | - Paul J Dyson
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL) CH-1015 Lausanne Switzerland
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Nyakuchena J, Ostresh S, Streater D, Pattengale B, Neu J, Fiankor C, Hu W, Kinigstein ED, Zhang J, Zhang X, Schmuttenmaer CA, Huang J. Direct Evidence of Photoinduced Charge Transport Mechanism in 2D Conductive Metal Organic Frameworks. J Am Chem Soc 2020; 142:21050-21058. [PMID: 33226217 DOI: 10.1021/jacs.0c09000] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Conductive metal organic frameworks (MOFs) represent a promising class of porous crystalline materials that have demonstrated potential in photo-electronics and photocatalytic applications. However, the lack of fundamental understanding on charge transport (CT) mechanism as well as the correlation of CT mechanism with their structure hampered their further development. Herein, we report the direct evidence of CT mechanism in 2D Cu-THQ MOFs and the correlation of temporal and spatial behaviors of charge carriers with their photoconductivity by combining three advanced spectroscopic methods, including time resolved optical and X-ray absorption spectroscopy and terahertz spectroscopy. In addition to Cu-THQ, the CT in Cu/Zn-THQ after incorporating Zn2+ guest metal was also examined to uncover the contribution of through space pathway, as the presence of the redox inactive 3d10 Zn2+ is expected to perturb the long range in-plane CT. We show that the hot carriers in Cu-THQ generated after photoexcitation are highly mobile and undergo fast localization to a lower energy state (cool carriers) with electrons occupying Cu center and holes in ligands. The cool carriers, which have super long lifetime (>17 ns), are responsible for the long-term photoconductivity in Cu-THQ and transport through the O-Cu-O motif with negligible contribution from interlayer ligand π-π stacking, as incorporation of Zn2+ in Cu-THQ significantly reduced photoconductivity. These unprecedented results not only demonstrate the capability to experimentally probe CT mechanism but also provide important insight in the rational design of 2D MOFs for photoelectronic and photocatalytic applications.
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Affiliation(s)
- James Nyakuchena
- Department of Chemistry, Marquette University, Milwaukee, 53201, United States
| | - Sarah Ostresh
- Department of Chemistry and Yale Energy Science Institute, Yale University, New Haven, Connecticut 06520, United States
| | - Daniel Streater
- Department of Chemistry, Marquette University, Milwaukee, 53201, United States
| | - Brian Pattengale
- Department of Chemistry and Yale Energy Science Institute, Yale University, New Haven, Connecticut 06520, United States
| | - Jens Neu
- Department of Molecular Biophysics and Biochemistry and Yale Microbial Sciences Institute, Yale University, New Haven, Connecticut 06520-8107, Unites States
| | - Christian Fiankor
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, United States
| | - Wenhui Hu
- Department of Chemistry, Marquette University, Milwaukee, 53201, United States
| | - Eli Diego Kinigstein
- X-ray Science Division, Argonne National Laboratory, Argonne, Illinois 60349, United States
| | - Jian Zhang
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, United States
| | - Xiaoyi Zhang
- X-ray Science Division, Argonne National Laboratory, Argonne, Illinois 60349, United States
| | - Charles A Schmuttenmaer
- Department of Chemistry and Yale Energy Science Institute, Yale University, New Haven, Connecticut 06520, United States
| | - Jier Huang
- Department of Chemistry, Marquette University, Milwaukee, 53201, United States
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