In the present work,a new combination of Raman and ultraviolet and visible(UV/Vis)absorption spectroelectrochemistry in reflection mode is proposed.The new experimental setup allows obtaining the two kinds of spectros...In the present work,a new combination of Raman and ultraviolet and visible(UV/Vis)absorption spectroelectrochemistry in reflection mode is proposed.The new experimental setup allows obtaining the two kinds of spectroscopic data without interferences concomitantly with the electrochemical information.To the best of our knowledge,it is the first time to report the simultaneous obtention of electrochemical,electronic,and vibrational information in the same experiment.This new combination provides time-resolved information about the processes that are taking place on the electrode/solution interface which has significant implications in different fields of chemistry,such as modification of electrodes,studies of electrocatalytic reaction mechanisms,development of sensors,among others.Two different systems were used to demonstrate the advantages and capabilities of the brand-new technique,namely,the oxidation of potassium ferrocyanide,an out-sphere system that is usually employed in the validation of SEC techniques,and the electrochemical-surface enhanced Raman spectroscopy(EC-SERS)detection of crystal violet by in-situ formation of the silver SERS substrate,where the UV/Vis spectra were used to follow the formation of the SERS substrate,whereas the Raman response of a probe molecule was used to confirm either the formation of a nanostructured surface and to obtain the fingerprint of the molecule with a high time resolution.The brand-new experimental setup has shown to be useful,versatile,robust,compact,and easy to use for future applications.展开更多
Un-doped and Cu-doped ZnS（ZnS：Cu） thin films were synthesized by Successive Ion Layer Absorption and Reaction（SILAR） method. The UV–visible absorption studies have been used to calculate the band gap values of t...Un-doped and Cu-doped ZnS（ZnS：Cu） thin films were synthesized by Successive Ion Layer Absorption and Reaction（SILAR） method. The UV–visible absorption studies have been used to calculate the band gap values of the fabricated ZnS：Cu thin films. It was observed that by increasing the concentration of Cu^2＋ ions, the Fermi level moves toward the edge of the valence band of ZnS. Photoluminescence spectra of un-doped and Cu-doped ZnS thin films was recorded under 355 nm. The emission spectrum of samples has a blue emission band at 436 nm.The peak positions of the luminescence showed a red shift as the Cu^2＋ C ion concentration was increased, which indicates that the acceptor level（of Cu^2＋） is getting close to the valence band of ZnS.展开更多
Sol-gel-derived nanoporous ZnO film has been successfully deposited on glass substrate at 200 °C and subsequently annealed at different temperatures of 300, 400 and 600 °C. Atomic force micrographs demonstra...Sol-gel-derived nanoporous ZnO film has been successfully deposited on glass substrate at 200 °C and subsequently annealed at different temperatures of 300, 400 and 600 °C. Atomic force micrographs demonstrated that the film was crack-free, and that granular nanoparticles were homogenously distributed on the film surface. The average grain size of the nanoparticles and RMS roughness of the scanned surface area was 10 nm and 13.6 nm, respectively, which is due to the high porosity of the film. Photoluminescence （PL） spectra of the nanoporous ZnO film at room temperature show a diffused band, which might be due to an increased amount of oxygen va- cancies on the lattice surface. The observed results of the nanoporous ZnO film indicates a promising application in the development of electrochemical biosensors due to the porosity of film enhancing the higher loading of biomacromolecules （enzyme and proteins）.展开更多
基金support from Ministerio de Ciencia e innovación(No.PID2020-113154RB-C21)Ministerio de Economía,Industria y Competitividad(No.CTQ2017-83935-RAEI/FEDERUE)+4 种基金Junta de Castilla y León(No.BU297P18)Ministerio de Ciencia,Innovación y Universidades(No.RED2018-102412-T)J.V.P-R acknowledges Spanish Ministry of Economy,Industry,and Competitiveness for the Juan de la Cierva postdoctoral(No.FJCI-2017-32458)the University of Alcalá(No.CCG19/CC-071)S.H.thanks JCyL and European Social Fund for her predoctoral fellowship.
文摘In the present work,a new combination of Raman and ultraviolet and visible(UV/Vis)absorption spectroelectrochemistry in reflection mode is proposed.The new experimental setup allows obtaining the two kinds of spectroscopic data without interferences concomitantly with the electrochemical information.To the best of our knowledge,it is the first time to report the simultaneous obtention of electrochemical,electronic,and vibrational information in the same experiment.This new combination provides time-resolved information about the processes that are taking place on the electrode/solution interface which has significant implications in different fields of chemistry,such as modification of electrodes,studies of electrocatalytic reaction mechanisms,development of sensors,among others.Two different systems were used to demonstrate the advantages and capabilities of the brand-new technique,namely,the oxidation of potassium ferrocyanide,an out-sphere system that is usually employed in the validation of SEC techniques,and the electrochemical-surface enhanced Raman spectroscopy(EC-SERS)detection of crystal violet by in-situ formation of the silver SERS substrate,where the UV/Vis spectra were used to follow the formation of the SERS substrate,whereas the Raman response of a probe molecule was used to confirm either the formation of a nanostructured surface and to obtain the fingerprint of the molecule with a high time resolution.The brand-new experimental setup has shown to be useful,versatile,robust,compact,and easy to use for future applications.
文摘Un-doped and Cu-doped ZnS（ZnS：Cu） thin films were synthesized by Successive Ion Layer Absorption and Reaction（SILAR） method. The UV–visible absorption studies have been used to calculate the band gap values of the fabricated ZnS：Cu thin films. It was observed that by increasing the concentration of Cu^2＋ ions, the Fermi level moves toward the edge of the valence band of ZnS. Photoluminescence spectra of un-doped and Cu-doped ZnS thin films was recorded under 355 nm. The emission spectrum of samples has a blue emission band at 436 nm.The peak positions of the luminescence showed a red shift as the Cu^2＋ C ion concentration was increased, which indicates that the acceptor level（of Cu^2＋） is getting close to the valence band of ZnS.
文摘Sol-gel-derived nanoporous ZnO film has been successfully deposited on glass substrate at 200 °C and subsequently annealed at different temperatures of 300, 400 and 600 °C. Atomic force micrographs demonstrated that the film was crack-free, and that granular nanoparticles were homogenously distributed on the film surface. The average grain size of the nanoparticles and RMS roughness of the scanned surface area was 10 nm and 13.6 nm, respectively, which is due to the high porosity of the film. Photoluminescence （PL） spectra of the nanoporous ZnO film at room temperature show a diffused band, which might be due to an increased amount of oxygen va- cancies on the lattice surface. The observed results of the nanoporous ZnO film indicates a promising application in the development of electrochemical biosensors due to the porosity of film enhancing the higher loading of biomacromolecules （enzyme and proteins）.
