Pursuing appropriate photo-active Li-ion storage materials and understanding their basic energy storage/conversion principle are pretty crucial for the rapidly developing photoassisted Li-ion batteries(PA-LIBs).Copper...Pursuing appropriate photo-active Li-ion storage materials and understanding their basic energy storage/conversion principle are pretty crucial for the rapidly developing photoassisted Li-ion batteries(PA-LIBs).Copper oxide(CuO)is one of the most popular candidates in both LIBs and photocatalysis.While CuO based PA-LIBs have never been reported yet.Herein,one-dimensional(1D)CuO nanowire arrays in situ grown on a three-dimensional(3D)copper foam support were employed as dualfunctional photoanode for both‘solar-to-electricity’and‘electricity-to-chemical’energy conversion in the PA-LIBs.It is found that light energy can be indeed stored and converted into electrical energy through the assembled CuO based PA-LIBs.Without external power source,the photo conversion efficiency of CuO based photocell reaches about 0.34%.Impressively,at a high current density of 4000 m A g^(-1),photoassisted discharge and charge specific capacity of CuO based PA-LIBs respectively receive 64.01%and 60.35%enhancement compared with the net electric charging and discharging process.Mechanism investigation reveals that photogenerated charges from CuO promote the interconversion between Cu^(2+)and Cu^(+)during the discharging/charging process,thus forcing the lithium storage reaction more completely and increasing the specific capacity of the PA-LIBs.This work can provide a general principle for the development of other high-efficient semiconductor-based PA-LIBs.展开更多
The conversion of carbon dioxide into value-added products is of great industrial and environmental interest. However, as carbon dioxide is relatively stable, the input energy required for this conversion is a signifi...The conversion of carbon dioxide into value-added products is of great industrial and environmental interest. However, as carbon dioxide is relatively stable, the input energy required for this conversion is a significant limiting factor in the system's performance. By utilising energy from the sun, through a range of key routes, this limitation can be overcome. In this review, we present a comprehensive and critical overview of the potential routes to harvest the sun's energy, primarily through solar-thermal technologies and plasmonic resonance effects. Focusing on the localised heating approach, this review shortlists and compares viable catalysts for the photo-thermal catalytic conversion of carbon dioxide.Further, the pathways and potential products of different carbon dioxide conversion routes are outlined with the reverse water gas shift,methanation, and methanol synthesis being of key interest. Finally, the challenges in implementing such systems and the outlook to the future are detailed.展开更多
The role of reduced graphene oxide（rGO） in the enhancement of photo-conversion efficiency of ZnO films for photoelectrochemical（PEC） water-splitting applications was analyzed. ZnO and rGO-hybridized ZnO（rGO/ZnO）...The role of reduced graphene oxide（rGO） in the enhancement of photo-conversion efficiency of ZnO films for photoelectrochemical（PEC） water-splitting applications was analyzed. ZnO and rGO-hybridized ZnO（rGO/ZnO） films were prepared via a two-step electrochemical deposition method followed by annealing at 300 °C under argon gas flow. The physical, optical and electrochemical properties of the films were characterized to identify the effect of rGO-hybridization on the applied bias photon-to-current efficiency（ABPE） of ZnO. Scanning electron microscopy and X-ray diffraction indicated the formation of verticallyaligned, wurtzite-phase ZnO nanorods. Diffuse-reflectance UV–visible spectroscopy indicated that rGO-hybridization was able to increase the light absorption range of the rGO/ZnO film. UPS analysis showed that hybridization with rGO increased the band gap of ZnO（3.56 eV） to 3.63 eV for rGO/ZnO sample,which may be attributed to the Burstein–Moss effect. Photoluminescence（PL） spectra disclosed that rGOhybridization suppressed electron-hole recombination due to crystal defects. Linear sweep voltammetry of the prepared thin films showed photocurrent density of 1.0 and 1.8 m A/cm;for ZnO and rGO/ZnO at+0.7 V, which corresponded to an ABPE of 0.55% and 0.95%, respectively. Thus, this report highlighted the multi-faceted role of rGO-hybridization in the enhancement of ZnO photo-conversion efficiency.展开更多
Using carbon felt,polytetrafluoroethylene latex and powder catalyst to assembly a light energy conversion device,the photocatalytic activity of catalyst 2.0%WO3-TiO2(2%WO3 compounding TiO2) with oxygen vacancies was s...Using carbon felt,polytetrafluoroethylene latex and powder catalyst to assembly a light energy conversion device,the photocatalytic activity of catalyst 2.0%WO3-TiO2(2%WO3 compounding TiO2) with oxygen vacancies was studied through the water splitting for O2 evolution,using a high pressure mercury lamp as the light source and Fe 3+ as the electron acceptor in two different devices:an ordinary photolysis device with catalyst powder suspending through a magnetic stirrer and a self-assembly light energy conversion device.The results show that after 12 h irradiation,the photocatalytic activity of 2.0%WO3-TiO2 with oxygen vacancies in the self-assembly light energy conversion device is higher than that of the ordinary photolysis device,and the amount of oxygen evolution is about 12 and 9 mmol/L respectively in these two devices.After 12 h,the rates of O2 evolution are slow in each device and the photocatalyst almost loses the photoactivity in the ordinary photolysis device.So,compared with the ordinary photocatalytic device,the rate of oxygen evolution and the life time of the catalyst are improved in the self-assembly light energy conversion device.展开更多
yb3＋/Dy3＋ co-doped A1203 nanopowders have been prepared by the non-aqueous sol-gel method and their up- conversion photoluminescence spectra are measured under excitation by a 980-nm semiconductor laser. The results...yb3＋/Dy3＋ co-doped A1203 nanopowders have been prepared by the non-aqueous sol-gel method and their up- conversion photoluminescence spectra are measured under excitation by a 980-nm semiconductor laser. The results show that there are comparatively abundant spectra of up-conversion emissions centered at 378, 408, 527 and 543, and 663 nm, corresponding to 4C9/2→ 6H13/2, 4C9/2→ 6Hll/2, 4115/2 → 6H13/2, and 4F9/2 →6Hll/2 transitions of Dy3＋, respectively. Two-photon and three-photon processes are involved in ultraviolet, violet, green, and red up-conversion emissions. The energy transition between Yb3＋ and Dy3＋ is discussed.展开更多
Dye-sensitized solar cells (DSSCs) with ZnO spin-coated TiO2 photo-electrodes are compared to DSSC with a bare TiO2 photo-electrode. It is demonstrated that the deposited ZnO of controlled amount, by varying the precu...Dye-sensitized solar cells (DSSCs) with ZnO spin-coated TiO2 photo-electrodes are compared to DSSC with a bare TiO2 photo-electrode. It is demonstrated that the deposited ZnO of controlled amount, by varying the precursor concentration in the coating sol, can indeed enhance the performance of the DSSC. The measured power conversion efficiency shows a maximum around the precursor concentration 0.1 M and falls down sharply to 0% beyond this point. The results are interpreted on the basis of two competing factors: At ZnO concentrations less than 0.1 M, the formation of an energy barrier increases the photocurrent by reducing the rate of interfacial back-recombination. At ZnO concentrations greater than 0.1 M, the screening of the TiO2 film by thicker ZnO layers decreases the photocurrent through the reduction of TiO2 dye-adsorption efficiency.展开更多
The unique photo-thermal energy conversion property of polar bear hairs has long been regarded as an essential element to enable this creature to survive in extremely cold conditions. However, the relevant research wa...The unique photo-thermal energy conversion property of polar bear hairs has long been regarded as an essential element to enable this creature to survive in extremely cold conditions. However, the relevant research was ineffectual to provide sufficient evidence of its solar energy harvesting property. In this paper, the properties of polar bear hairs were analyzed and compared systematically with those of domestic sheep wool through the measurements in the aspects of photo-thermal conversion effi- ciency, scanning electron microscope, fluorescence spectral and transmission of UV-visible spectra. Moreover, this study was much more focused on exploring ultraviolet utilization property of polar bear hair than previous research. The research results demonstrated that the photo-thermal property of polar bear hair was superior to those of wool fiber, especially in harvesting ultraviolet part. The potential benefits of this research lie in the development of bionic solar energy collective devices, especially in artificial solar energy collection fibers and textile products.展开更多
基金supported by the Laboratory of Lingnan Modern Agriculture Project(NZ2021029)the National Natural Science Foundation of China(Nos.21802046 and 21972048)。
文摘Pursuing appropriate photo-active Li-ion storage materials and understanding their basic energy storage/conversion principle are pretty crucial for the rapidly developing photoassisted Li-ion batteries(PA-LIBs).Copper oxide(CuO)is one of the most popular candidates in both LIBs and photocatalysis.While CuO based PA-LIBs have never been reported yet.Herein,one-dimensional(1D)CuO nanowire arrays in situ grown on a three-dimensional(3D)copper foam support were employed as dualfunctional photoanode for both‘solar-to-electricity’and‘electricity-to-chemical’energy conversion in the PA-LIBs.It is found that light energy can be indeed stored and converted into electrical energy through the assembled CuO based PA-LIBs.Without external power source,the photo conversion efficiency of CuO based photocell reaches about 0.34%.Impressively,at a high current density of 4000 m A g^(-1),photoassisted discharge and charge specific capacity of CuO based PA-LIBs respectively receive 64.01%and 60.35%enhancement compared with the net electric charging and discharging process.Mechanism investigation reveals that photogenerated charges from CuO promote the interconversion between Cu^(2+)and Cu^(+)during the discharging/charging process,thus forcing the lithium storage reaction more completely and increasing the specific capacity of the PA-LIBs.This work can provide a general principle for the development of other high-efficient semiconductor-based PA-LIBs.
文摘The conversion of carbon dioxide into value-added products is of great industrial and environmental interest. However, as carbon dioxide is relatively stable, the input energy required for this conversion is a significant limiting factor in the system's performance. By utilising energy from the sun, through a range of key routes, this limitation can be overcome. In this review, we present a comprehensive and critical overview of the potential routes to harvest the sun's energy, primarily through solar-thermal technologies and plasmonic resonance effects. Focusing on the localised heating approach, this review shortlists and compares viable catalysts for the photo-thermal catalytic conversion of carbon dioxide.Further, the pathways and potential products of different carbon dioxide conversion routes are outlined with the reverse water gas shift,methanation, and methanol synthesis being of key interest. Finally, the challenges in implementing such systems and the outlook to the future are detailed.
基金University of Malaya for their financial support through the High Impact Research (HIR) grant no.H-21001-F0032Nanocat Laboratory for analytical testing
文摘The role of reduced graphene oxide（rGO） in the enhancement of photo-conversion efficiency of ZnO films for photoelectrochemical（PEC） water-splitting applications was analyzed. ZnO and rGO-hybridized ZnO（rGO/ZnO） films were prepared via a two-step electrochemical deposition method followed by annealing at 300 °C under argon gas flow. The physical, optical and electrochemical properties of the films were characterized to identify the effect of rGO-hybridization on the applied bias photon-to-current efficiency（ABPE） of ZnO. Scanning electron microscopy and X-ray diffraction indicated the formation of verticallyaligned, wurtzite-phase ZnO nanorods. Diffuse-reflectance UV–visible spectroscopy indicated that rGO-hybridization was able to increase the light absorption range of the rGO/ZnO film. UPS analysis showed that hybridization with rGO increased the band gap of ZnO（3.56 eV） to 3.63 eV for rGO/ZnO sample,which may be attributed to the Burstein–Moss effect. Photoluminescence（PL） spectra disclosed that rGOhybridization suppressed electron-hole recombination due to crystal defects. Linear sweep voltammetry of the prepared thin films showed photocurrent density of 1.0 and 1.8 m A/cm;for ZnO and rGO/ZnO at+0.7 V, which corresponded to an ABPE of 0.55% and 0.95%, respectively. Thus, this report highlighted the multi-faceted role of rGO-hybridization in the enhancement of ZnO photo-conversion efficiency.
基金Project(2010CL04) supported by the Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation, ChinaProject(K-081025) supported by State Key Laboratory Breeding Base of Photocatalysis,Fuzhou University,China
文摘Using carbon felt,polytetrafluoroethylene latex and powder catalyst to assembly a light energy conversion device,the photocatalytic activity of catalyst 2.0%WO3-TiO2(2%WO3 compounding TiO2) with oxygen vacancies was studied through the water splitting for O2 evolution,using a high pressure mercury lamp as the light source and Fe 3+ as the electron acceptor in two different devices:an ordinary photolysis device with catalyst powder suspending through a magnetic stirrer and a self-assembly light energy conversion device.The results show that after 12 h irradiation,the photocatalytic activity of 2.0%WO3-TiO2 with oxygen vacancies in the self-assembly light energy conversion device is higher than that of the ordinary photolysis device,and the amount of oxygen evolution is about 12 and 9 mmol/L respectively in these two devices.After 12 h,the rates of O2 evolution are slow in each device and the photocatalyst almost loses the photoactivity in the ordinary photolysis device.So,compared with the ordinary photocatalytic device,the rate of oxygen evolution and the life time of the catalyst are improved in the self-assembly light energy conversion device.
基金Project supported by the National Natural Science Foundation of China （Grant No. 11004092） and the Scientific Research Fund of Education Department of Liaoning Province, China （Grant No. 2009A417）.
文摘yb3＋/Dy3＋ co-doped A1203 nanopowders have been prepared by the non-aqueous sol-gel method and their up- conversion photoluminescence spectra are measured under excitation by a 980-nm semiconductor laser. The results show that there are comparatively abundant spectra of up-conversion emissions centered at 378, 408, 527 and 543, and 663 nm, corresponding to 4C9/2→ 6H13/2, 4C9/2→ 6Hll/2, 4115/2 → 6H13/2, and 4F9/2 →6Hll/2 transitions of Dy3＋, respectively. Two-photon and three-photon processes are involved in ultraviolet, violet, green, and red up-conversion emissions. The energy transition between Yb3＋ and Dy3＋ is discussed.
文摘Dye-sensitized solar cells (DSSCs) with ZnO spin-coated TiO2 photo-electrodes are compared to DSSC with a bare TiO2 photo-electrode. It is demonstrated that the deposited ZnO of controlled amount, by varying the precursor concentration in the coating sol, can indeed enhance the performance of the DSSC. The measured power conversion efficiency shows a maximum around the precursor concentration 0.1 M and falls down sharply to 0% beyond this point. The results are interpreted on the basis of two competing factors: At ZnO concentrations less than 0.1 M, the formation of an energy barrier increases the photocurrent by reducing the rate of interfacial back-recombination. At ZnO concentrations greater than 0.1 M, the screening of the TiO2 film by thicker ZnO layers decreases the photocurrent through the reduction of TiO2 dye-adsorption efficiency.
基金Projects(52106125,52206216,52076217)supported by the National Natural Science Foundation of ChinaProject(2023JJ40744)supported by the Natural Science Foundation of Hunan Province,China+1 种基金Project(2021RC4006)supported by the Science and Technology Innovation Program of Hunan Province,ChinaProject supported by the High Performance Computing Center of Central South University,China。
文摘The unique photo-thermal energy conversion property of polar bear hairs has long been regarded as an essential element to enable this creature to survive in extremely cold conditions. However, the relevant research was ineffectual to provide sufficient evidence of its solar energy harvesting property. In this paper, the properties of polar bear hairs were analyzed and compared systematically with those of domestic sheep wool through the measurements in the aspects of photo-thermal conversion effi- ciency, scanning electron microscope, fluorescence spectral and transmission of UV-visible spectra. Moreover, this study was much more focused on exploring ultraviolet utilization property of polar bear hair than previous research. The research results demonstrated that the photo-thermal property of polar bear hair was superior to those of wool fiber, especially in harvesting ultraviolet part. The potential benefits of this research lie in the development of bionic solar energy collective devices, especially in artificial solar energy collection fibers and textile products.
