1
|
Rybińska-Fryca A, Mikolajczyk A, Łuczak J, Paszkiewicz-Gawron M, Paszkiewicz M, Zaleska-Medynska A, Puzyn T. How thermal stability of ionic liquids leads to more efficient TiO2-based nanophotocatalysts: Theoretical and experimental studies. J Colloid Interface Sci 2020; 572:396-407. [DOI: 10.1016/j.jcis.2020.03.079] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 03/10/2020] [Accepted: 03/22/2020] [Indexed: 12/20/2022]
|
2
|
Wu WT, Chen CH, Chiang CY, Chau LK. Effect of Surface Coverage of Gold Nanoparticles on the Refractive Index Sensitivity in Fiber-Optic Nanoplasmonic Sensing. SENSORS (BASEL, SWITZERLAND) 2018; 18:E1759. [PMID: 29857535 PMCID: PMC6021843 DOI: 10.3390/s18061759] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 05/24/2018] [Accepted: 05/25/2018] [Indexed: 11/16/2022]
Abstract
A simple theoretical model was developed to analyze the extinction spectrum of gold nanoparticles (AuNPs) on the fiber core and glass surfaces in order to aid the determination of the surface coverage and surface distribution of the AuNPs on the fiber core surface for sensitivity optimization of the fiber optic particle plasmon resonance (FOPPR) sensor. The extinction spectrum of AuNPs comprises of the interband absorption of AuNPs, non-interacting plasmon resonance (PR) band due to isolated AuNPs, and coupled PR band of interacting AuNPs. When the surface coverage is smaller than 12.2%, the plasmon coupling effect can almost be ignored. This method is also applied to understand the refractive index sensitivity of the FOPPR sensor with respect to the non-interacting PR band and the coupled PR band. In terms of wavelength sensitivity at a surface coverage of 18.6%, the refractive index sensitivity of the coupled PR band (205.5 nm/RIU) is greater than that of the non-interacting PR band (349.1 nm/RIU). In terms of extinction sensitivity, refractive index sensitivity of the coupled PR band (-3.86/RIU) is similar to that of the non-interacting PR band (-3.93/RIU). Both maximum wavelength and extinction sensitivities were found at a surface coverage of 15.2%.
Collapse
Affiliation(s)
- Wei-Te Wu
- Department of Biomechatronics Engineering, National Pingtung University of Science and Technology, Pingtung 912, Taiwan.
| | - Chien-Hsing Chen
- Department of Chemistry and Biochemistry and Center for Nano Bio-Detection, National Chung Cheng University, Chiayi 621, Taiwan.
| | - Chang-Yue Chiang
- Department of Chemistry and Biochemistry and Center for Nano Bio-Detection, National Chung Cheng University, Chiayi 621, Taiwan.
| | - Lai-Kwan Chau
- Department of Chemistry and Biochemistry and Center for Nano Bio-Detection, National Chung Cheng University, Chiayi 621, Taiwan.
| |
Collapse
|
3
|
Tobaldi DM, Hortigüela Gallo MJ, Otero-Irurueta G, Singh MK, Pullar RC, Seabra MP, Labrincha JA. Purely Visible-Light-Induced Photochromism in Ag-TiO 2 Nanoheterostructures. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:4890-4902. [PMID: 28463002 DOI: 10.1021/acs.langmuir.6b04474] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We report titania nanoheterostructures decorated with silver, exhibiting tuneable photochromic properties for the first time when stimulated only by visible white light (domestic indoor lamp), with no UV wavelengths. Photochromic materials show reversible color changes under light exposure. However, all inorganic photochromic nanoparticles (NPs) require UV light to operate. Conventionally, multicolor photochromism in Ag-TiO2 films involves a change in color to brownish-gray during UV-light irradiation (i.e., reduction of Ag+ to Ag0) and a (re)bleaching (i.e., (re)oxidation of Ag0 to colorless Ag+) upon visible-light exposure. In this work, on the contrary, we demonstrate visible-light-induced photochromism (ranging from yellow to violet) of 1-10 mol % Ag-modified titania NPs using both spectroscopic and colorimetric CIEL*a*b* analyses. This is not a bleaching of the UV-induced color but a change in color itself under exposure to visible light, and it is shown to be a completely different mechanism-driven by the interfacial charge transfer of an electron from the valence band of TiO2 to that of the AgxO clusters that surround the titania-to the usual UV-triggered photochromism reported in titania-based materials. The quantity of Ag or irradiation time dictated the magnitude and degree of tuneability of the color change, from pale yellow to dark blue, with a rapid change visible only after a few seconds, and the intensity and red shift of surface plasmon resonance induced under visible light also increased. This effect was reversible after annealing in the dark at 100 °C/15 min. Photocatalytic activity under visible light was also assessed against the abatement of nitrogen oxide pollutants, for interior use, therefore showing the coexistence of photochromism and photocatalysis-both triggered by the same wavelength-in the same material, making it a multifunctional material. Moreover, we also demonstrate and explain why X-ray photoelectron spectroscopy is an unreliable technique with such materials.
Collapse
Affiliation(s)
- D M Tobaldi
- Department of Materials and Ceramic Engineering/CICECO-Aveiro Institute of Materials and ‡Center for Mechanical Technology and Automation-TEMA, Department of Mechanical Engineering, University of Aveiro , Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
| | - M J Hortigüela Gallo
- Department of Materials and Ceramic Engineering/CICECO-Aveiro Institute of Materials and ‡Center for Mechanical Technology and Automation-TEMA, Department of Mechanical Engineering, University of Aveiro , Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
| | - G Otero-Irurueta
- Department of Materials and Ceramic Engineering/CICECO-Aveiro Institute of Materials and ‡Center for Mechanical Technology and Automation-TEMA, Department of Mechanical Engineering, University of Aveiro , Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
| | - M K Singh
- Department of Materials and Ceramic Engineering/CICECO-Aveiro Institute of Materials and ‡Center for Mechanical Technology and Automation-TEMA, Department of Mechanical Engineering, University of Aveiro , Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
| | - R C Pullar
- Department of Materials and Ceramic Engineering/CICECO-Aveiro Institute of Materials and ‡Center for Mechanical Technology and Automation-TEMA, Department of Mechanical Engineering, University of Aveiro , Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
| | - M P Seabra
- Department of Materials and Ceramic Engineering/CICECO-Aveiro Institute of Materials and ‡Center for Mechanical Technology and Automation-TEMA, Department of Mechanical Engineering, University of Aveiro , Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
| | - J A Labrincha
- Department of Materials and Ceramic Engineering/CICECO-Aveiro Institute of Materials and ‡Center for Mechanical Technology and Automation-TEMA, Department of Mechanical Engineering, University of Aveiro , Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
| |
Collapse
|
4
|
Pilarczyk K, Daly B, Podborska A, Kwolek P, Silverson VA, de Silva AP, Szaciłowski K. Coordination chemistry for information acquisition and processing. Coord Chem Rev 2016. [DOI: 10.1016/j.ccr.2016.04.012] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
|
5
|
Rtimi S, Sanjines R, Pulgarin C, Houas A, Lavanchy JC, Kiwi J. Coupling of narrow and wide band-gap semiconductors on uniform films active in bacterial disinfection under low intensity visible light: implications of the interfacial charge transfer (IFCT). JOURNAL OF HAZARDOUS MATERIALS 2013; 260:860-868. [PMID: 23867967 DOI: 10.1016/j.jhazmat.2013.06.019] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Revised: 06/07/2013] [Accepted: 06/09/2013] [Indexed: 06/02/2023]
Abstract
This study reports the design, preparation, testing and surface characterization of uniform films deposited by sputtering Ag and Ta on non-heat resistant polyester to evaluate the Escherichia coli inactivation by TaON, TaN/Ag, Ag and TaON/Ag polyester. Co-sputtering for 120 s Ta and Ag in the presence of N₂ and O₂ led to the faster E. coli inactivation by a TaON/Ag sample within ∼40 min under visible light irradiation. The deconvolution of TaON/Ag peaks obtained by X-ray photoelectron spectroscopy (XPS) allowed the assignment of the Ta₂O₅ and Ag-species. The shifts observed for the XPS peaks have been assigned to AgO to Ag₂O and Ag(0), and are a function of the applied sputtering times. The mechanism of interfacial charge transfer (IFCT) from the Ag₂O conduction band (cb) to the lower laying Ta₂O₅ (cb) is discussed suggesting a reaction mechanism. The optical absorption of the TaON and TaON/Ag samples found by diffuse reflectance spectroscopy (DRS) correlated well with the kinetics of E. coli inactivation. The TaON/Ag sample microstructure was characterized by contact angle (CA) and by atomic force microscopy (AFM). Self-cleaning of the TaON/Ag polyester after each disinfection cycle enabled repetitive E. coli inactivation.
Collapse
Affiliation(s)
- S Rtimi
- Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-GPAO, Station 6, CH-1015 Lausanne, Switzerland.
| | | | | | | | | | | |
Collapse
|
6
|
Kwolek P, Oszajca M, Szaciłowski K. Catecholate and 2,3-acenediolate complexes of d0 ions as prospective materials for molecular electronics and spintronics. Coord Chem Rev 2012. [DOI: 10.1016/j.ccr.2012.03.028] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
7
|
Macyk W, Szaciłowski K, Stochel G, Buchalska M, Kuncewicz J, Łabuz P. Titanium(IV) complexes as direct TiO2 photosensitizers. Coord Chem Rev 2010. [DOI: 10.1016/j.ccr.2009.12.037] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
8
|
Gaweda S, Podborska A, Macyk W, Szaciłowski K. Nanoscale optoelectronic switches and logic devices. NANOSCALE 2009; 1:299-316. [PMID: 20648267 DOI: 10.1039/b9nr00145j] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The photoelectrochemical photocurrent switching (PEPS) effect, in the beginning regarded as a scientific curiosity, has become a field of extensive study for numerous research groups all over the world. This unique effect can be utilized for nanoscale switching and information processing, furthermore, is can serve as an interface between molecular information processing and macroscopic electronics. This review summarizes recent efforts in understanding photocurrent switching effects and their application for the construction of nanoscale switches and logic devices. Furthermore, some future prospects concerning the development of electronic/optoelectronic devices based on photoactive semiconducting hybrid materials are presented.
Collapse
Affiliation(s)
- Sylwia Gaweda
- Uniwersytet Jagielloński, Wydział Chemii, Kraków, Poland
| | | | | | | |
Collapse
|
9
|
Petroski J, Chou M, Creutz C. The coordination chemistry of gold surfaces: Formation and far-infrared spectra of alkanethiolate-capped gold nanoparticles. J Organomet Chem 2009. [DOI: 10.1016/j.jorganchem.2008.11.057] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
10
|
Okamoto A, Nakamura R, Osawa H, Hashimoto K. Site-specific synthesis of oxo-bridged mixed-valence binuclear complexes on mesoporous silica. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:7011-7017. [PMID: 18503283 DOI: 10.1021/la704032c] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We report the site-specific synthesis of mixed valence TiIV-O-FeII complexes within the pores of ordered mesoporous silica (SBA-15). By using 6-di- tert-butylpyridine as the selective activator of tripodally linked TiIV-OH groups of Ti-grafted SBA-15, the FeCl2.4H2O complexes reacted selectively with the nucleophilic TiIV-O(-) groups. The formation of Si-O-FeII byproducts, due to the reaction with the abundant Si-OH groups, was successfully restricted and the selectivity for forming the TiIV-O-FeII complexes exceeded 80%. The metal-metal interaction of TiIV-O-FeII complexes was confirmed by the appearance of TiIV/FeII --> TiIII/Fe III metal-to-metal charge transfer band, and their coordination, valency, and spin state were characterized by diffuse transmission UV-vis, Fourier transform IR, and Fe K-edge X-ray absorption fine structure measurements. It was also confirmed that the present methods can be extended to other metal combinations of TiIV-O-NiII and TiIV-O-MnII. The electron transfer processes occurring under photoinduced metal-to-metal charge transfer of oxo-bridged mixed valence complexes on silica supports have recently been proven as a new class of visible-light-sensitive redox centers. Thus, the present synthetic procedure allows the fabrication of a variety of photochemical reaction centers according to the molecular-level design.
Collapse
Affiliation(s)
- Akihiro Okamoto
- Department of Applied Chemistry, School of Engineering, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | | | | | | |
Collapse
|
11
|
Harris JA, Trotter K, Brunschwig BS. Interfacial Electron Transfer in Metal Cyanide-Sensitized TiO2 Nanoparticles. J Phys Chem B 2007; 111:6695-702. [PMID: 17402776 DOI: 10.1021/jp0679313] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Electroabsorption (Stark) spectroscopy has been used to study the charge-transfer absorption from a transition-metal-cyanide complex to a TiO2 nanoparticle. Transition-metal cyanide/TiO2(particle) systems were synthesized using FeII(CN)(6)4-, RuII(CN)6(4-), MoIV(CN)(8)4-, and WIV(CN)8(4-). On formation of the M(CN)n4-/TiO2(particle) system, a new metal-to-particle charge-transfer (MPCT) absorption band is observed in the 390-480 nm region. Analysis of the absorption spectra suggests that the TiO2 level involved in the MPCT transition resides at significantly higher energy than the bottom of the conduction band and that the electronic coupling between the two metal centers is the dominant factor determining the position of the MPCT band maximum. The average charge-transfer distances determined by Stark spectra range from 4.1-4.7 A. The observation of relatively short charge-transfer distances leads to the conclusion that the MPCT absorption is from the transition-metal cyanide center to a level that is localized on the Ti atom bound to a nitrogen end of the [O2Ti-N-C-M(CN)x] system. The electronic coupling, Hab, calculated for a two state model is similar to values observed in dinuclear metal complexes.
Collapse
Affiliation(s)
- James A Harris
- Molecular Materials Research Center, Beckman Institute, MC 139-74, California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, USA
| | | | | |
Collapse
|
12
|
Creutz C. Nonadiabatic, Short-Range, Intramolecular Electron Transfer from Ruthenium(II) to Cobalt(III) Complexes. J Phys Chem B 2007; 111:6713-7. [PMID: 17388525 DOI: 10.1021/jp0687450] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The activation parameters reported for intramolecular electron-transfer between ruthenium(II) and cobalt(III) complexes have been corrected for the thermodynamic contributions of the entropy change for the reaction DeltaS0 to the entropy of activation DeltaS*, and it is concluded that these electron-transfers range from adiabatic (pyrazine bridge) to highly nonadiabatic. The electronic factors are about 20 times smaller than for diruthenium mixed-valence complexes. Spanning the metal-metal separation range of 7-14 A over which beta=0.7 A-1, the electron-transfer rates are dominated by the electronic factors, which change three times more with separation than do the nuclear factors.
Collapse
Affiliation(s)
- Carol Creutz
- Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973-5000, USA
| |
Collapse
|
13
|
Creutz C, Brunschwig BS, Sutin N. Interfacial charge-transfer absorption: 3. Application to semiconductor-molecule assemblies. J Phys Chem B 2007; 110:25181-90. [PMID: 17165962 DOI: 10.1021/jp063953d] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Interfacial charge-transfer absorption (IFCTA) provides information concerning the barriers to charge transfer between molecules and the energy levels of a metal/semiconductor and the magnitude of the electronic coupling and could thus provide a powerful tool for understanding interfacial charge-transfer kinetics. Here we utilize a previously published model (J. Phys. Chem. B 2005, 109, 10251) to predict the energetics of IFCTA spectra for semiconductors and compare literature observations to these predictions for n-type semiconductors (largely TiO2). In contrast to metals, where IFCTA has been only rarely observed, new absorption features due to IFCTA are common for semiconductors such as TiO2. At issue is whether the electron accepting states in the TiO2 are localized or delocalized over the conduction band.
Collapse
Affiliation(s)
- Carol Creutz
- Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973-5000, USA.
| | | | | |
Collapse
|