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
Ophiopogonis polysaccharide-iron(Ⅲ)(OPI)was prepared and characterized in the present study.The optimum condition for preparing OPI was as follows:OP and trisodium citrate were mixed at a weight ratio of 4:1 and reac...Ophiopogonis polysaccharide-iron(Ⅲ)(OPI)was prepared and characterized in the present study.The optimum condition for preparing OPI was as follows:OP and trisodium citrate were mixed at a weight ratio of 4:1 and reacted in a water bath at 70°C for 3 h within the pH range of 8.0–8.5.Aggregation morphology or structure of OPI in aqueous solution and solid state was studied by scanning electron microscopy,transmission electron microscopy and small-angle X-ray diffraction.In aqueous solution,OPI could self-assemble into micron vesicles with flower-shaped morphology.Results of X-ray diffraction showed OPI with layered structure.A core-shell model was proposed for OPI.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.
基金Key Laboratory of Traditional Chinese Medicine Quality and Standard,Gansu University of Chinese Medicine,Lanzhou,China(Grant No.ZYZL18-006)
文摘Ophiopogonis polysaccharide-iron(Ⅲ)(OPI)was prepared and characterized in the present study.The optimum condition for preparing OPI was as follows:OP and trisodium citrate were mixed at a weight ratio of 4:1 and reacted in a water bath at 70°C for 3 h within the pH range of 8.0–8.5.Aggregation morphology or structure of OPI in aqueous solution and solid state was studied by scanning electron microscopy,transmission electron microscopy and small-angle X-ray diffraction.In aqueous solution,OPI could self-assemble into micron vesicles with flower-shaped morphology.Results of X-ray diffraction showed OPI with layered structure.A core-shell model was proposed for OPI.
