The degradation of ethinylestradiol (EE, an orally bio-active estrogen) in an aqueous-methanolic solution using a Ti/TiO2 thin-film electrode and UV radiation (a photoelectrocatalytic system) was evaluated. Hence, HPL...The degradation of ethinylestradiol (EE, an orally bio-active estrogen) in an aqueous-methanolic solution using a Ti/TiO2 thin-film electrode and UV radiation (a photoelectrocatalytic system) was evaluated. Hence, HPLC/UV analysis shows that EE (at 0.34 mmol) is totally consumed after 30 minutes of exposure to the photoelectrocatalytic system in the presence of Na2SO4 (0.1 mol·L-1) and with an applied bias potential of +1.0 V versus the Ag/AgCl reference electrode. Moreover, monitoring by direct infusion electrospray ionization mass spectrometry (ESI-MS) and SPME-GC/ MS (solid phase microextraction coupled with gas chromatography-mass spectrometry) reveals that apparently no degradation products are formed under these conditions. Hence, this study demonstrates that the photoelectrocatalytic system can be efficiently used to promote the complete degradation (and likely mineralization) of this hormone under these conditions.展开更多
Photocatalytic oxidation kinetics of thiophene in n-octane/water extraction system was studied with fluorine and ferric ion codoped nano-TiO_2(nano-F^-/Fe^(3+)/TiO_2) powders used as the photocatalyst.Effects of initi...Photocatalytic oxidation kinetics of thiophene in n-octane/water extraction system was studied with fluorine and ferric ion codoped nano-TiO_2(nano-F^-/Fe^(3+)/TiO_2) powders used as the photocatalyst.Effects of initial concentration of thiophene and additional dosage of F^-/Fe^(3+)/TiO_2 on the reaction rate constant and half-life were investigated.The results showed that the appropriately added dosage of F^-/Fe^(3+)/TiO_2 was 0.1 g in the 100-mL reaction system and the photooxidative kinetics of thiophene in the presence of F^-/Fe^(3+)/TiO_2 catalyst was of first-order with a rate constant of 0.6508 h^(-1) and a half-life of 1.0651 h.The desulfurization rate of thiophene was 98.1%in 5 h and the sulfur content could be reduced from 800 ppm to 15 ppm.The reaction rate constant increased with a decreasing initial concentration of thiophene.展开更多
A process capable of simultaneously oxidizing NO, SO2, and Hg^0 was proposed, using a nigh-voltage and short-duration positive pulsed corona discharge. By focusing on NO, SO2, and Hg^0 oxidation efficiencies, the infl...A process capable of simultaneously oxidizing NO, SO2, and Hg^0 was proposed, using a nigh-voltage and short-duration positive pulsed corona discharge. By focusing on NO, SO2, and Hg^0 oxidation efficiencies, the influences of pulse peak voltage, pulse frequency, initial concentration, electrode number, residence time and water vapor addition were investigated. The results indicate that NO, SO2 and Hg^0 oxidation efficiencies depend primarily on the radicals (OH, HO2, O) and the active species (O3, H2O2, etc.) produced by the pulsed corona discharge. The NO, SO2 and Hg^0 oxidation efficiencies could be improved as pulse peak voltage, pulse frequency, electrode number and residence time increased, but they were reduced with increasing initial concentrations. By adding water vapor, the SO2 oxidation efficiency was improved remarkably, while the NO oxidation efficiency decreased slightly. In our experiments, the simultaneous NO, SO2, and Hg^0 oxidation efficiencies reached to 40%, 98%, and 55% with the initial concentrations 479 mg/m^3, 1040 mg/m^3, and 15.0 μg/m^3, respectively.展开更多
TiO_(2)has demonstrated outstanding performance in electrochemical advanced oxidation processes(EAOPs)due to its structural stability and high oxygen overpotential.However,there is still much room for improving its el...TiO_(2)has demonstrated outstanding performance in electrochemical advanced oxidation processes(EAOPs)due to its structural stability and high oxygen overpotential.However,there is still much room for improving its electrochemical activity.Herein,narrow bandgap manganese oxide(MnO_(x))was composited with TiO_(2)nanotube arrays(TiO_(2)NTAs)that in-situ oxidized on porous Ti sponge,forming the MnO_(x)-TiO_(2)NTAs anode.XANES and XPS analysis further proved that the composition of MnO_(x)is Mn2O3.Electrochemical characterizations revealed that increasing the composited concentration of MnO_(x)can improve the conductivity and reduce oxygen evolution potential so as to improve the electrochemical activity of the composited MnO_(x)-TiO_(2)NTAs anode.Meanwhile,the optimal degradation rate of benzoic acid(BA)was achieved using MnO_(x)-TiO_(2)NTAs with a MnO_(x)concentration of 0.1 mmol L^(-1),and the role of MnO_(x)was proposed based on DFT calculation.Additionally,the required electrical energy(EE/O)to destroy BA was optimized by varying the composited concentration of MnO_(x)and the degradation voltage.These quantitative results are of great significance for the design and application of high-performance materials for EAOPs.展开更多
Electrochemical reduction of CO2 to produce value-added feedstock chemicals using high-performance electrocatalysts is a promising protocol to address the excessive CO2 in the atmosphere and the energy crisis. However...Electrochemical reduction of CO2 to produce value-added feedstock chemicals using high-performance electrocatalysts is a promising protocol to address the excessive CO2 in the atmosphere and the energy crisis. However, the high overpotential, low current density, and poor product selectivity for CO2 electroreduction greatly impede their practical applications. In this work, we develop an efficient catalyst for CO2 reduction to CO consisting of well-dispersed ZrO2 nanoparticles tightly anchored on nitrogendoped carbon nanosheets(ZrO2/N-C) for the first time. Importantly, the ZrO2 nanoparticles possess oxygen vacancies and defects, which regulate the electronic structure of catalyst and thus greatly enhance the electrocatalytic activity. Specifically, ZrO2/N-C demonstrates a high CO Faradaic efficiency(FE) of 64% at-0.4 V vs. the reversible hydrogen electrode(RHE) and a respectable current density of ~2.6 m A cm-2 in CO2-saturated 0.5 M KHCO 3 solution. This work opens a new avenue for developing excellent catalysts for CO2 electroreduction with metal oxide/heteroatom-doped carbon composite structure.展开更多
Electrochemical carbon dioxide(CO_(2))reduction(ECR)is a promising technology to produce valuable fuels and feedstocks from CO_(2).Despite large efforts to develop ECR catalysts,the investigation of the catalytic perf...Electrochemical carbon dioxide(CO_(2))reduction(ECR)is a promising technology to produce valuable fuels and feedstocks from CO_(2).Despite large efforts to develop ECR catalysts,the investigation of the catalytic performance and electrochemical behavior of complex metal oxides,especially perovskite oxides,is rarely reported.Here,the inorganic perovskite oxide Ag-doped(La_(0.8)Sr_(0.2))_(0.95)Ag_(0.05)MnO_(3-δ)(LSA0.05M)is reported as an efficient electrocatalyst for ECR to CO for the first time,which exhibits a Faradaic efficiency(FE)of 84.3%,a remarkable mass activity of 75Ag^(-1)(normalized to the mass of Ag),and stability of 130 h at a moderate overpotential of 0.79 V.The LSA0.05M catalyst experiences structure reconstruction during ECR,creating the in operando-formed interface between the perovskite and the evolved Ag phase.The evolved Ag is uniformly distributed with a small particle size on the perovskite surface.Theoretical calculations indicate the reconstruction of LSA0.05M during ECR and reveal that the perovskite-Ag interface provides adsorption sites for CO_(2) and accelerates the desorption of the*CO intermediate to enhance ECR.This study presents a novel high-performance perovskite catalyst for ECR andmay inspire the future design of electrocatalysts via the in operando formation of metal-metal oxide interfaces.展开更多
Objective The selective loss of dopaminergic neurons in Parkinson's disease is suspected to correlate with the increase of cellular iron, which may be involved in the pathogenesis of PD by promotion of oxidative stre...Objective The selective loss of dopaminergic neurons in Parkinson's disease is suspected to correlate with the increase of cellular iron, which may be involved in the pathogenesis of PD by promotion of oxidative stress. This research investigated dopamine-induced oxidative stress toxicity contributed by iron and the production of dopamine-derived neurotoxins in dopaminergic SH-SYSY cells. Methods After the SH-SYSY cells were pre-incubated with dopamine and Fe^2+ for 24 h, the cell viability, hydroxyl radical, melondialdehyde, cell apoptosis, and catechol isoquinolines were measured by lactate dehydrogenase assay, salicylic acid trapping method, thiobarbuteric acid assay, Hoechst 33258 staining and HPLC-electrochemical detection (HPLC-ECD), respectively. Results (1) Optimal dopamine (150 μmol/L) and Fe^2+ (40 or 80 μmol/L) significantly increased the concentrations of hydroxy radicals and melondialdehyde in SH-SYSY cells. (2) Induction with dopamine alone or dopamine and Fe^2+ (dopamine/Fe^2+) caused cell apoptosis. (3) Compared with untreated cells, the catechol isoquinolines, salsolinol and N-methyl-salsolinol in dopamine/Fe^2+-induced cells were detected in increasing amounts. Conclusion Due to dopamine/Fe^2+-induced oxidative stress similar to the state in the parkinsonian substantia nigra neurons, dopamine and Fe^2+ impaired SH-SYSY cells could be used as the cell oxidative stress model of Parkinson's disease. The catechol isoquinolines detected in cells may be involved in the pathogenesis of Parkinson's disease as potential neurotoxins.展开更多
Yb-doped TiO2 pastes with different Yb/TiO2 weight ratios are prepared in the sol-gel process to obtain dyesensitized solar cells (DSCs). The nanocrystalline size of Yb-TiO2 becomes smaller and the lattice parameter...Yb-doped TiO2 pastes with different Yb/TiO2 weight ratios are prepared in the sol-gel process to obtain dyesensitized solar cells (DSCs). The nanocrystalline size of Yb-TiO2 becomes smaller and the lattice parameters change. Lattice distortion is observed and dark current is detected. It is found that a part of Yb existing as insulating oxide Yb2O3 state acts as barrier layers at the electrode-electrolyte interface to suppress charge recombination. A Yb-doped TiO2 electrode applied in DSCs leads to a higher open-circuit voltage and a higher fill factor. How the Yb-doped TiO2 films affect the photovoltaic response of DSCs is discussed.展开更多
In this work,we initially synthesized Sb2S3 with uniform flower-like structures via a facile hydrothermal method through the modification of the Sb source and pH value.Afterward,Sb2S3 with a nanosheet structure was su...In this work,we initially synthesized Sb2S3 with uniform flower-like structures via a facile hydrothermal method through the modification of the Sb source and pH value.Afterward,Sb2S3 with a nanosheet structure was successfully synthesized on reduced graphene oxide(Sb2S3@RGO).The flower-like Sb2S3 and the Sb2S3@RGO nanosheets were tested as the counter electrode(CE)of dye-sensitized solar cells,and the latter exhibited a higher electrocatalytic property than the former owing to the introduction of graphene.The results from electrochemical tests indicated that the as-prepared Sb2S3@RGO nanosheets possess higher catalytic activity,charge-transfer ability,and electrochemical stability than Sb2S3,RGO,and Pt CEs.More notably,the power conversion efficiency of Sb2S3@RGO reached 8.17%,which was higher than that of the standard Pt CE(7.75%).展开更多
An easy method for preparing CuO nanoparticles incorporated in a mesoporous structure was presented based on the thermal decomposition of a copper complex. The novel copper coordination compound of [Cu(anic)<sub>...An easy method for preparing CuO nanoparticles incorporated in a mesoporous structure was presented based on the thermal decomposition of a copper complex. The novel copper coordination compound of [Cu(anic)<sub>2</sub>]·0.75H<sub>2</sub>O (anic= 2-aminonicotinate) with the microflake morphology was synthesized through the reaction of 2-aminonicotinic acid (Hanic) and copper(II) nitrate. Using elemental analysis and Fourier transform infrared (FTIR) spectroscopy, the chemical composition of CuC<sub>12</sub>H<sub>11.5</sub>N<sub>4</sub>O<sub>4.75</sub> was proposed. Calcination process at 550 °C for 4 h transformed the microflakes into CuO nanoparticles incorporated in a mesoporous structure. The FTIR peaks assigned to 2-aminonicotinate were completely removed after calcination, confirming CuO formation. X-ray diffraction (XRD) analysis also confirmed the generation of pure and crystalline CuO. SEM showed CuO nanoparticles with the average diameter of 75 nm. The diffuse reflectance spectrum (DRS) of the CuO nanoparticles showed a band gap energy of −1.58 eV. The degradation efficiency toward rhodamine B was almost 100 % after 5 h illumination when both CuO and H<sub>2</sub>O<sub>2</sub> were utilized. The results show that the product can be used as an efficient photocatalyst for water treatment.展开更多
The efficiency of photo-electrocatalytic(PECa) devices for the production of solar fuels depends on several limiting factors such as light harvesting, charge recombination and mass transport diffusion. We analyse he...The efficiency of photo-electrocatalytic(PECa) devices for the production of solar fuels depends on several limiting factors such as light harvesting, charge recombination and mass transport diffusion. We analyse here how they influence the performances in PECa cells having a photo-anode based on Au-modified TiOnanotube(TNT) arrays, with the aim of developing design criteria to optimize the photo-anode and the PECa cell configuration for water photo-electrolysis(splitting) and ethanol photo-reforming processes.The TNT samples were prepared by controlled anodic oxidation of Ti foils and then decorated with gold nanoparticles using different techniques to enhance the visible light response through heterojunction and plasmonic effects. The activity tests were made in a gas-phase reactor, as well as in a PECa cell without applied bias. Results were analysed in terms of photo-generated current, Hproduction rate and photoconversion efficiency. Particularly, a solar-to-hydrogen efficiency of 0.83% and a Faradaic efficiency of 91%were obtained without adding sacrificial reagents.展开更多
文摘The degradation of ethinylestradiol (EE, an orally bio-active estrogen) in an aqueous-methanolic solution using a Ti/TiO2 thin-film electrode and UV radiation (a photoelectrocatalytic system) was evaluated. Hence, HPLC/UV analysis shows that EE (at 0.34 mmol) is totally consumed after 30 minutes of exposure to the photoelectrocatalytic system in the presence of Na2SO4 (0.1 mol·L-1) and with an applied bias potential of +1.0 V versus the Ag/AgCl reference electrode. Moreover, monitoring by direct infusion electrospray ionization mass spectrometry (ESI-MS) and SPME-GC/ MS (solid phase microextraction coupled with gas chromatography-mass spectrometry) reveals that apparently no degradation products are formed under these conditions. Hence, this study demonstrates that the photoelectrocatalytic system can be efficiently used to promote the complete degradation (and likely mineralization) of this hormone under these conditions.
文摘Photocatalytic oxidation kinetics of thiophene in n-octane/water extraction system was studied with fluorine and ferric ion codoped nano-TiO_2(nano-F^-/Fe^(3+)/TiO_2) powders used as the photocatalyst.Effects of initial concentration of thiophene and additional dosage of F^-/Fe^(3+)/TiO_2 on the reaction rate constant and half-life were investigated.The results showed that the appropriately added dosage of F^-/Fe^(3+)/TiO_2 was 0.1 g in the 100-mL reaction system and the photooxidative kinetics of thiophene in the presence of F^-/Fe^(3+)/TiO_2 catalyst was of first-order with a rate constant of 0.6508 h^(-1) and a half-life of 1.0651 h.The desulfurization rate of thiophene was 98.1%in 5 h and the sulfur content could be reduced from 800 ppm to 15 ppm.The reaction rate constant increased with a decreasing initial concentration of thiophene.
基金supported by the Science and Technology Research of Department of Education of China (No. 0305,03087)
文摘A process capable of simultaneously oxidizing NO, SO2, and Hg^0 was proposed, using a nigh-voltage and short-duration positive pulsed corona discharge. By focusing on NO, SO2, and Hg^0 oxidation efficiencies, the influences of pulse peak voltage, pulse frequency, initial concentration, electrode number, residence time and water vapor addition were investigated. The results indicate that NO, SO2 and Hg^0 oxidation efficiencies depend primarily on the radicals (OH, HO2, O) and the active species (O3, H2O2, etc.) produced by the pulsed corona discharge. The NO, SO2 and Hg^0 oxidation efficiencies could be improved as pulse peak voltage, pulse frequency, electrode number and residence time increased, but they were reduced with increasing initial concentrations. By adding water vapor, the SO2 oxidation efficiency was improved remarkably, while the NO oxidation efficiency decreased slightly. In our experiments, the simultaneous NO, SO2, and Hg^0 oxidation efficiencies reached to 40%, 98%, and 55% with the initial concentrations 479 mg/m^3, 1040 mg/m^3, and 15.0 μg/m^3, respectively.
基金the support from the Brook Byers Institute for Sustainable Systems,Hightower ChairGeorgia Research Alliance at the Georgia Institute of Technology。
文摘TiO_(2)has demonstrated outstanding performance in electrochemical advanced oxidation processes(EAOPs)due to its structural stability and high oxygen overpotential.However,there is still much room for improving its electrochemical activity.Herein,narrow bandgap manganese oxide(MnO_(x))was composited with TiO_(2)nanotube arrays(TiO_(2)NTAs)that in-situ oxidized on porous Ti sponge,forming the MnO_(x)-TiO_(2)NTAs anode.XANES and XPS analysis further proved that the composition of MnO_(x)is Mn2O3.Electrochemical characterizations revealed that increasing the composited concentration of MnO_(x)can improve the conductivity and reduce oxygen evolution potential so as to improve the electrochemical activity of the composited MnO_(x)-TiO_(2)NTAs anode.Meanwhile,the optimal degradation rate of benzoic acid(BA)was achieved using MnO_(x)-TiO_(2)NTAs with a MnO_(x)concentration of 0.1 mmol L^(-1),and the role of MnO_(x)was proposed based on DFT calculation.Additionally,the required electrical energy(EE/O)to destroy BA was optimized by varying the composited concentration of MnO_(x)and the degradation voltage.These quantitative results are of great significance for the design and application of high-performance materials for EAOPs.
基金The financial supports from the National 1000 Young Talents Program of Chinathe National Natural Science Foundation of China (Grant no. 21603078)
文摘Electrochemical reduction of CO2 to produce value-added feedstock chemicals using high-performance electrocatalysts is a promising protocol to address the excessive CO2 in the atmosphere and the energy crisis. However, the high overpotential, low current density, and poor product selectivity for CO2 electroreduction greatly impede their practical applications. In this work, we develop an efficient catalyst for CO2 reduction to CO consisting of well-dispersed ZrO2 nanoparticles tightly anchored on nitrogendoped carbon nanosheets(ZrO2/N-C) for the first time. Importantly, the ZrO2 nanoparticles possess oxygen vacancies and defects, which regulate the electronic structure of catalyst and thus greatly enhance the electrocatalytic activity. Specifically, ZrO2/N-C demonstrates a high CO Faradaic efficiency(FE) of 64% at-0.4 V vs. the reversible hydrogen electrode(RHE) and a respectable current density of ~2.6 m A cm-2 in CO2-saturated 0.5 M KHCO 3 solution. This work opens a new avenue for developing excellent catalysts for CO2 electroreduction with metal oxide/heteroatom-doped carbon composite structure.
基金Australian Centre for Neutron ScatteringAustralian Nuclear Science and Technology Organisation,Grant/Award Number:MI8046+1 种基金Max Planck-POSTECH-Hsinchu Center for Complex Phase MaterialsHigh-Performance Computing Center of Nanjing Tech University。
文摘Electrochemical carbon dioxide(CO_(2))reduction(ECR)is a promising technology to produce valuable fuels and feedstocks from CO_(2).Despite large efforts to develop ECR catalysts,the investigation of the catalytic performance and electrochemical behavior of complex metal oxides,especially perovskite oxides,is rarely reported.Here,the inorganic perovskite oxide Ag-doped(La_(0.8)Sr_(0.2))_(0.95)Ag_(0.05)MnO_(3-δ)(LSA0.05M)is reported as an efficient electrocatalyst for ECR to CO for the first time,which exhibits a Faradaic efficiency(FE)of 84.3%,a remarkable mass activity of 75Ag^(-1)(normalized to the mass of Ag),and stability of 130 h at a moderate overpotential of 0.79 V.The LSA0.05M catalyst experiences structure reconstruction during ECR,creating the in operando-formed interface between the perovskite and the evolved Ag phase.The evolved Ag is uniformly distributed with a small particle size on the perovskite surface.Theoretical calculations indicate the reconstruction of LSA0.05M during ECR and reveal that the perovskite-Ag interface provides adsorption sites for CO_(2) and accelerates the desorption of the*CO intermediate to enhance ECR.This study presents a novel high-performance perovskite catalyst for ECR andmay inspire the future design of electrocatalysts via the in operando formation of metal-metal oxide interfaces.
基金This work was supported by the National Natural Science Foundation of China (No. 20435020, No. 20275005, and No. 30670645).
文摘Objective The selective loss of dopaminergic neurons in Parkinson's disease is suspected to correlate with the increase of cellular iron, which may be involved in the pathogenesis of PD by promotion of oxidative stress. This research investigated dopamine-induced oxidative stress toxicity contributed by iron and the production of dopamine-derived neurotoxins in dopaminergic SH-SYSY cells. Methods After the SH-SYSY cells were pre-incubated with dopamine and Fe^2+ for 24 h, the cell viability, hydroxyl radical, melondialdehyde, cell apoptosis, and catechol isoquinolines were measured by lactate dehydrogenase assay, salicylic acid trapping method, thiobarbuteric acid assay, Hoechst 33258 staining and HPLC-electrochemical detection (HPLC-ECD), respectively. Results (1) Optimal dopamine (150 μmol/L) and Fe^2+ (40 or 80 μmol/L) significantly increased the concentrations of hydroxy radicals and melondialdehyde in SH-SYSY cells. (2) Induction with dopamine alone or dopamine and Fe^2+ (dopamine/Fe^2+) caused cell apoptosis. (3) Compared with untreated cells, the catechol isoquinolines, salsolinol and N-methyl-salsolinol in dopamine/Fe^2+-induced cells were detected in increasing amounts. Conclusion Due to dopamine/Fe^2+-induced oxidative stress similar to the state in the parkinsonian substantia nigra neurons, dopamine and Fe^2+ impaired SH-SYSY cells could be used as the cell oxidative stress model of Parkinson's disease. The catechol isoquinolines detected in cells may be involved in the pathogenesis of Parkinson's disease as potential neurotoxins.
文摘Yb-doped TiO2 pastes with different Yb/TiO2 weight ratios are prepared in the sol-gel process to obtain dyesensitized solar cells (DSCs). The nanocrystalline size of Yb-TiO2 becomes smaller and the lattice parameters change. Lattice distortion is observed and dark current is detected. It is found that a part of Yb existing as insulating oxide Yb2O3 state acts as barrier layers at the electrode-electrolyte interface to suppress charge recombination. A Yb-doped TiO2 electrode applied in DSCs leads to a higher open-circuit voltage and a higher fill factor. How the Yb-doped TiO2 films affect the photovoltaic response of DSCs is discussed.
基金funded by the Tianjin science and technology support key projects(18YFZCSF00500)the National Science Fund for Distinguished Young Scholars(21425729)the National Natural Science Foundation of China
文摘In this work,we initially synthesized Sb2S3 with uniform flower-like structures via a facile hydrothermal method through the modification of the Sb source and pH value.Afterward,Sb2S3 with a nanosheet structure was successfully synthesized on reduced graphene oxide(Sb2S3@RGO).The flower-like Sb2S3 and the Sb2S3@RGO nanosheets were tested as the counter electrode(CE)of dye-sensitized solar cells,and the latter exhibited a higher electrocatalytic property than the former owing to the introduction of graphene.The results from electrochemical tests indicated that the as-prepared Sb2S3@RGO nanosheets possess higher catalytic activity,charge-transfer ability,and electrochemical stability than Sb2S3,RGO,and Pt CEs.More notably,the power conversion efficiency of Sb2S3@RGO reached 8.17%,which was higher than that of the standard Pt CE(7.75%).
基金Iran University of Science and Technology, the Research Council of Sharif University of Technology and Iran Nanotechnology Initiative Council for financial support
文摘An easy method for preparing CuO nanoparticles incorporated in a mesoporous structure was presented based on the thermal decomposition of a copper complex. The novel copper coordination compound of [Cu(anic)<sub>2</sub>]·0.75H<sub>2</sub>O (anic= 2-aminonicotinate) with the microflake morphology was synthesized through the reaction of 2-aminonicotinic acid (Hanic) and copper(II) nitrate. Using elemental analysis and Fourier transform infrared (FTIR) spectroscopy, the chemical composition of CuC<sub>12</sub>H<sub>11.5</sub>N<sub>4</sub>O<sub>4.75</sub> was proposed. Calcination process at 550 °C for 4 h transformed the microflakes into CuO nanoparticles incorporated in a mesoporous structure. The FTIR peaks assigned to 2-aminonicotinate were completely removed after calcination, confirming CuO formation. X-ray diffraction (XRD) analysis also confirmed the generation of pure and crystalline CuO. SEM showed CuO nanoparticles with the average diameter of 75 nm. The diffuse reflectance spectrum (DRS) of the CuO nanoparticles showed a band gap energy of −1.58 eV. The degradation efficiency toward rhodamine B was almost 100 % after 5 h illumination when both CuO and H<sub>2</sub>O<sub>2</sub> were utilized. The results show that the product can be used as an efficient photocatalyst for water treatment.
基金The TERRA(Tandem Electrocatalytic Reactor for energy/Resource efficiency and process intensification,H2020 project 677471)Eco~2CO_2(Eco-friendly biorefinery fine chemicals from CO_2 photo-catalytic reduction,FP7 project 309701)
文摘The efficiency of photo-electrocatalytic(PECa) devices for the production of solar fuels depends on several limiting factors such as light harvesting, charge recombination and mass transport diffusion. We analyse here how they influence the performances in PECa cells having a photo-anode based on Au-modified TiOnanotube(TNT) arrays, with the aim of developing design criteria to optimize the photo-anode and the PECa cell configuration for water photo-electrolysis(splitting) and ethanol photo-reforming processes.The TNT samples were prepared by controlled anodic oxidation of Ti foils and then decorated with gold nanoparticles using different techniques to enhance the visible light response through heterojunction and plasmonic effects. The activity tests were made in a gas-phase reactor, as well as in a PECa cell without applied bias. Results were analysed in terms of photo-generated current, Hproduction rate and photoconversion efficiency. Particularly, a solar-to-hydrogen efficiency of 0.83% and a Faradaic efficiency of 91%were obtained without adding sacrificial reagents.