The solar-driven catalytic conversion of CO2 to useful chemical fuels is regarded as an environmentally friendly approach to reduce the consumption of fossil fuels and mitigate the greenhouse effect.However,it is high...The solar-driven catalytic conversion of CO2 to useful chemical fuels is regarded as an environmentally friendly approach to reduce the consumption of fossil fuels and mitigate the greenhouse effect.However,it is highly intriguing and challenging to promote the selectivity and efficiency of visible-light-responsive photocatalysts that favor the adsorption of CO2 in photoreduction processes.In this work,three-dimensional hierarchical Cd0.8Zn0.2S flowers(C8Z2S-F)with ultrathin petals were successfully synthesized through an in-situ self-assembly growth process using sodium citrate as a morphology director.The flower-like Cd0.8Zn0.2S solid solution exhibited remarkable photocatalytic performance in the reduction of CO2,generating CO up to 41.4μmol g^−1 under visible-light illumination for 3 h;this was nearly three times greater than that of Cd0.8Zn0.2S nanoparticles(C8Z2S-NP)(14.7μmol g^−1).Particularly,a comparably high selectivity of 89.9%for the conversion of CO2 to CO,with a turnover number of 39.6,was obtained from the solar-driven C8Z2S-F system in the absence of any co-catalyst or sacrificial agent.Terahertz time-domain spectroscopy indicated that the introduction of flower structures enhanced the light-harvesting capacity of C8Z2S-F.The in situ diffuse reflectance infrared Fourier transform spectroscopy unveiled the existence of surface-adsorbed species and the conversion of photoreduction intermediates during the photocatalytic process.Empirical characterizations and predictions of the photocatalytic mechanism demonstrated that the flower-like Cd0.8Zn0.2S solid solution possessed desirable CO2 adsorption properties and an enhanced charge-transfer capability,thus providing a highly effective photocatalytic reduction of CO2.展开更多
以磁控溅射制备的ZnO纳米晶薄膜作为籽晶层,用水热法在80℃氧化铟锡(indium tin oxide,ITO)玻璃衬底上,实现了大面积ZnO纳米线阵列膜的取向生长,制备了3种金属-半导体-金属(metal-semiconductor-metal,MSM)结构的ZnO半导体纳米线阵列膜...以磁控溅射制备的ZnO纳米晶薄膜作为籽晶层,用水热法在80℃氧化铟锡(indium tin oxide,ITO)玻璃衬底上,实现了大面积ZnO纳米线阵列膜的取向生长,制备了3种金属-半导体-金属(metal-semiconductor-metal,MSM)结构的ZnO半导体纳米线阵列膜样品,测试了薄膜样品的光学特性和I-V特性。结果表明:在相同的生长液浓度下,籽晶层对所生长的纳米线尺度分布有显著影响。所制备的纳米线薄膜在室温下具有显著的紫外带边发射特性。ZnO纳米线/Ag和ZnO纳米线/Al的金属-半导体接触均具有明显的Schottky接触特性,而ZnO纳米线/Au的金属-半导体接触具有明显Ohmic接触特性。展开更多
文摘The solar-driven catalytic conversion of CO2 to useful chemical fuels is regarded as an environmentally friendly approach to reduce the consumption of fossil fuels and mitigate the greenhouse effect.However,it is highly intriguing and challenging to promote the selectivity and efficiency of visible-light-responsive photocatalysts that favor the adsorption of CO2 in photoreduction processes.In this work,three-dimensional hierarchical Cd0.8Zn0.2S flowers(C8Z2S-F)with ultrathin petals were successfully synthesized through an in-situ self-assembly growth process using sodium citrate as a morphology director.The flower-like Cd0.8Zn0.2S solid solution exhibited remarkable photocatalytic performance in the reduction of CO2,generating CO up to 41.4μmol g^−1 under visible-light illumination for 3 h;this was nearly three times greater than that of Cd0.8Zn0.2S nanoparticles(C8Z2S-NP)(14.7μmol g^−1).Particularly,a comparably high selectivity of 89.9%for the conversion of CO2 to CO,with a turnover number of 39.6,was obtained from the solar-driven C8Z2S-F system in the absence of any co-catalyst or sacrificial agent.Terahertz time-domain spectroscopy indicated that the introduction of flower structures enhanced the light-harvesting capacity of C8Z2S-F.The in situ diffuse reflectance infrared Fourier transform spectroscopy unveiled the existence of surface-adsorbed species and the conversion of photoreduction intermediates during the photocatalytic process.Empirical characterizations and predictions of the photocatalytic mechanism demonstrated that the flower-like Cd0.8Zn0.2S solid solution possessed desirable CO2 adsorption properties and an enhanced charge-transfer capability,thus providing a highly effective photocatalytic reduction of CO2.
文摘以磁控溅射制备的ZnO纳米晶薄膜作为籽晶层,用水热法在80℃氧化铟锡(indium tin oxide,ITO)玻璃衬底上,实现了大面积ZnO纳米线阵列膜的取向生长,制备了3种金属-半导体-金属(metal-semiconductor-metal,MSM)结构的ZnO半导体纳米线阵列膜样品,测试了薄膜样品的光学特性和I-V特性。结果表明:在相同的生长液浓度下,籽晶层对所生长的纳米线尺度分布有显著影响。所制备的纳米线薄膜在室温下具有显著的紫外带边发射特性。ZnO纳米线/Ag和ZnO纳米线/Al的金属-半导体接触均具有明显的Schottky接触特性,而ZnO纳米线/Au的金属-半导体接触具有明显Ohmic接触特性。
