The kinetics of interracial processes of CdSe thin film electrode before and after sur- face modification of 1,1'-di linolene ferrocenyl L-B films have been studied in K_4Fe(CN)_6 solution by Intensity Modulated P...The kinetics of interracial processes of CdSe thin film electrode before and after sur- face modification of 1,1'-di linolene ferrocenyl L-B films have been studied in K_4Fe(CN)_6 solution by Intensity Modulated Photocurrent Spectroscopy(IMPS).Potential dependence of surface state relaxation time(T_s),steady state photocurrent(I_s),collection coefficient of minority carriers(G_o), rate constant of photocorrosion(K_(cr)),and density of surface state(N_(ss))were determined in terms of frequency response analysis of IMPS plots.展开更多
n-Si（111） surface tailed -C2H5, -C2H4COOH, -C2H2COOH were prepared by the reactions among Si-H to ethyl-Grignard, methyl acrylate and ethyl propionate, and the carboxyls were formed under the existence of trifluoroa...n-Si（111） surface tailed -C2H5, -C2H4COOH, -C2H2COOH were prepared by the reactions among Si-H to ethyl-Grignard, methyl acrylate and ethyl propionate, and the carboxyls were formed under the existence of trifluoroacetic acid. The composite n-Si（111） electrodes were obtained by depositing Pt nanodots and the photovoltaic characteristics for these electrodes were studied in I^-/I3^- redox electrolyte. The j-U （photo current density-potential） behaviors of photo-voltage and photocurrent densities to the electrodes under solar illumination varied regularly with groups of -C2H2COOH〉-C2H4COOH〉-H〉-C2H5. The photo-voltage and photocurrent density of the electrode tailed -C2 H2COOH were -0.641 V and 5.25 mA/cm^2, respectively, more negative than those of the non-conjugated modification.展开更多
CONSPECTUS:Increasing concentrations of atmospheric CO_(2)are a worldwide problem that have triggered considerable environmental concerns,such as global warming,glacier melting,and a loss of biodiversity.Therefore,the...CONSPECTUS:Increasing concentrations of atmospheric CO_(2)are a worldwide problem that have triggered considerable environmental concerns,such as global warming,glacier melting,and a loss of biodiversity.Therefore,the conversion and utilization of CO_(2)have become increasingly urgent.CO_(2)photoreduction mimics natural photosynthesis and performs CO_(2)reduction by using solar energy to drive the formation of renewable fuels,which has been documented as a potential solution for energy shortage and global warming.CO_(2)photoreduction is a promising approach for achieving energy sustainability by forming and utilizing C-based reduction products.The traditional thermocatalytic CO_(2)reduction technique requires high temperature and high-pressure conditions,which consumes huge energy amounts;by contrast,CO_(2)photoreduction employs solar energy and electrical energy as the activation energy for catalytic reaction,resulting in faster reaction rates and minimal environmental impact.Although semiconductor-based photocatalysts are advantageous,given their low cost and easy modification,their slow carrier transfer rates and poor photostabilities limit their use in practical applications.Homogenous catalysts consisting of integrated photosensitizers and catalyst units on the surface of semiconductor electrodes can provide more appropriate photocatalytic capabilities for simultaneous CO_(2)photoreduction and water oxidation.However,differences in reaction conditions for the two half reactions,with the integration of water oxidation and CO_(2)reduction in single one-catalyst systems,may be inaccessible.To overcome these bottlenecks,a variety of approaches for artificial photosynthesis have been investigated to achieve more highly efficient CO_(2)photoreduction,and these strategies primarily focused on the optimization of the surface structures of semiconductor electrodes and the development of novel catalysts.When the basic principles of the molecular chemical reaction are combined with surface construction preparations,the photocatalytic activity can be efficiently enhanced.This Account summarizes the mechanisms for CO_(2)photoreduction in a Dye-Sensitized PhotoElectrochemical Cell(DSPEC),and it outlines the progress made in this area based on the design and assembly of molecular-based DSPEC and the role of chromophore−catalyst assemblies in these applications.By optimizing surface film internal structures,surface molecular assemblies have been prepared that open a door for preparing durable,efficient integrated assemblies for CO_(2)photoreduction.In addition,this Account also briefly summarizes the research progress of a typical tandem DSPEC cell for coupling CO_(2)reduction with water oxidation.Based on the research progress and challenges of semiconductor-surface molecular catalyst design,prospects are outlined at the end of the Account,including enhancement of catalytic behaviors and long-term stability,optimization of the surface assembly structures,and novel design of efficient bias-free tandem cells.展开更多
基金This work was supported by the National Natural Science Foundation of China
文摘The kinetics of interracial processes of CdSe thin film electrode before and after sur- face modification of 1,1'-di linolene ferrocenyl L-B films have been studied in K_4Fe(CN)_6 solution by Intensity Modulated Photocurrent Spectroscopy(IMPS).Potential dependence of surface state relaxation time(T_s),steady state photocurrent(I_s),collection coefficient of minority carriers(G_o), rate constant of photocorrosion(K_(cr)),and density of surface state(N_(ss))were determined in terms of frequency response analysis of IMPS plots.
基金We are grateful to the Project of the National Natural Science Foundation of China(Grant No.50602004)the support from Chinese Education for Back Student Abroad and the fund for Young Teacher of BUCT(Project No.QN0512)for financial support.
文摘n-Si（111） surface tailed -C2H5, -C2H4COOH, -C2H2COOH were prepared by the reactions among Si-H to ethyl-Grignard, methyl acrylate and ethyl propionate, and the carboxyls were formed under the existence of trifluoroacetic acid. The composite n-Si（111） electrodes were obtained by depositing Pt nanodots and the photovoltaic characteristics for these electrodes were studied in I^-/I3^- redox electrolyte. The j-U （photo current density-potential） behaviors of photo-voltage and photocurrent densities to the electrodes under solar illumination varied regularly with groups of -C2H2COOH〉-C2H4COOH〉-H〉-C2H5. The photo-voltage and photocurrent density of the electrode tailed -C2 H2COOH were -0.641 V and 5.25 mA/cm^2, respectively, more negative than those of the non-conjugated modification.
基金supported by the Ningbo Top-Talent Team Program,Program for the National Natural Science Foundation of China(22106166)the Yongjiang Innovative Individual Introduction of China,and the China Postdoctoral Science Foundation(2022M723253).
文摘CONSPECTUS:Increasing concentrations of atmospheric CO_(2)are a worldwide problem that have triggered considerable environmental concerns,such as global warming,glacier melting,and a loss of biodiversity.Therefore,the conversion and utilization of CO_(2)have become increasingly urgent.CO_(2)photoreduction mimics natural photosynthesis and performs CO_(2)reduction by using solar energy to drive the formation of renewable fuels,which has been documented as a potential solution for energy shortage and global warming.CO_(2)photoreduction is a promising approach for achieving energy sustainability by forming and utilizing C-based reduction products.The traditional thermocatalytic CO_(2)reduction technique requires high temperature and high-pressure conditions,which consumes huge energy amounts;by contrast,CO_(2)photoreduction employs solar energy and electrical energy as the activation energy for catalytic reaction,resulting in faster reaction rates and minimal environmental impact.Although semiconductor-based photocatalysts are advantageous,given their low cost and easy modification,their slow carrier transfer rates and poor photostabilities limit their use in practical applications.Homogenous catalysts consisting of integrated photosensitizers and catalyst units on the surface of semiconductor electrodes can provide more appropriate photocatalytic capabilities for simultaneous CO_(2)photoreduction and water oxidation.However,differences in reaction conditions for the two half reactions,with the integration of water oxidation and CO_(2)reduction in single one-catalyst systems,may be inaccessible.To overcome these bottlenecks,a variety of approaches for artificial photosynthesis have been investigated to achieve more highly efficient CO_(2)photoreduction,and these strategies primarily focused on the optimization of the surface structures of semiconductor electrodes and the development of novel catalysts.When the basic principles of the molecular chemical reaction are combined with surface construction preparations,the photocatalytic activity can be efficiently enhanced.This Account summarizes the mechanisms for CO_(2)photoreduction in a Dye-Sensitized PhotoElectrochemical Cell(DSPEC),and it outlines the progress made in this area based on the design and assembly of molecular-based DSPEC and the role of chromophore−catalyst assemblies in these applications.By optimizing surface film internal structures,surface molecular assemblies have been prepared that open a door for preparing durable,efficient integrated assemblies for CO_(2)photoreduction.In addition,this Account also briefly summarizes the research progress of a typical tandem DSPEC cell for coupling CO_(2)reduction with water oxidation.Based on the research progress and challenges of semiconductor-surface molecular catalyst design,prospects are outlined at the end of the Account,including enhancement of catalytic behaviors and long-term stability,optimization of the surface assembly structures,and novel design of efficient bias-free tandem cells.
