The conversion of CO2 into new carbon-based products, such as fuels and chemicals, is an attractive and promising means of mitigating global energy needs and minimizing environmental damage. Although bismuth tungstate (Bi2WO6) as a photocatalyst can promote CO2 photoreduction, a systematic study for the development of a low-cost and efficient catalyst is needed. Thus, Bi2WO6 with different morphologies was successfully synthesized using the hydrothermal method. An experimental design was applied to investigate the effect of synthesis time and PVP (polyvinylpyrrolidone) concentration on catalyst photocatalytic activity. Crystal structures, morphologies, optical absorption, and surface charges of the catalysts were characterized by X-ray diffraction, scanning electron microscope, UV-vis diffuse-reflection spectroscopy, nitrogen adsorption, and zeta potential. All samples exhibited good performance for the photoreduction of CO2 into ethanol, and both time and PVP concentration were significant in the ethanol yield. Changes in synthesis conditions induced differences in catalyst characteristics, such as morphology, crystallinity, and, predominantly, surface area. Furthermore, PVP addition improved photocatalytic efficiency by up to 258% compared with results without the surfactant. The best sample, W-8h-10%, presented a flower-like morphology and ethanol yield of 68.9 μmol g-1 h-1.

中文翻译：

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加入PVP增强Bi2WO6的光催化活性，可在可见光下将CO2还原为乙醇。

将CO2转换为新的碳基产品（例如燃料和化学药品）是缓解全球能源需求和最大程度减少环境破坏的有吸引力且有希望的手段。尽管钨酸铋（Bi2WO6）作为光催化剂可以促进CO2的光还原，但仍需要对开发低成本高效催化剂的系统研究。因此，使用水热法成功地合成了不同形态的Bi2WO6。应用实验设计来研究合成时间和PVP（聚乙烯吡咯烷酮）浓度对催化剂光催化活性的影响。用X射线衍射，扫描电子显微镜，紫外可见漫反射光谱，氮吸附，X射线衍射等方法表征了催化剂的晶体结构，形貌，光吸收和表面电荷。和ζ电位。所有样品均表现出将CO2光还原为乙醇的良好性能，时间和PVP浓度均对乙醇产量有重要影响。合成条件的变化引起催化剂特性的差异，例如形态，结晶度以及主要是表面积。此外，与没有表面活性剂的结果相比，添加PVP可以将光催化效率提高多达258％。最佳样品W-8h-10％呈现花状形态，乙醇收率为68.9μmolg-1 h-1。表面积。此外，与没有表面活性剂的结果相比，添加PVP可以将光催化效率提高多达258％。最佳样品W-8h-10％呈现花状形态，乙醇收率为68.9μmolg-1 h-1。表面积。此外，与没有表面活性剂的结果相比，添加PVP可以将光催化效率提高多达258％。最佳样品W-8h-10％呈现花状形态，乙醇收率为68.9μmolg-1 h-1。