Abstract:

The use of photocatalytic technology to convert atmospheric CO₂ into high-value-added chemical raw materials is an effective way to alleviate energy and environmental problems. In this work, BiOBr was synthesized via a hydrothermal method, and polyvinylpyrrolidone (PVP) was used to regulate the morphology of BiOBr. The catalyst characterization results show that nano-spherical BiOBr-xP (x represents the amount of PVP introduced) was successfully prepared by introducing PVP. Compared with BiOBr, BiOBr-xP has a larger specific surface area and increases the exposure probability of active sites. Meanwhile, the use of PVP improved the band structure of BiOBr, resulting in a more negative conduction band potential for BiOBr-xP, effectively improving its reduction capacity. Photocatalytic CO₂ reduction tests indicate that BiOBr-2P exhibits optimal photocatalytic activity, achieving a CO generation rate of 2.74 μmol‧g^-1‧h^-1, which is 3.38 times greater than that of BiOBr without PVP (0.81 μmol‧g^-1‧h^-1).

Key words: photocatalysis, carbon dioxide, carbon monoxide, morphology, BiOBr

摘要：

利用光催化技术将大气中的CO₂转化为高附加值的化学原料，是缓解能源和环境问题的有效方法。通过水热法制备了BiOBr，并采用聚乙烯吡咯烷酮（PVP）调控BiOBr的形貌。分析催化剂表征结果可知，引入PVP可成功制备得到纳米球状的BiOBr-xP（x表示引入PVP的量），相比于BiOBr，BiOBr-xP具有更大的比表面积，提高了活性位点的暴露概率。同时，PVP的引入改善了BiOBr的能带结构，BiOBr-xP的导带电势更负，有效提高了BiOBr的还原能力。光催化CO₂还原测试结果表明，BiOBr-2P具有最佳的光催化CO₂还原活性，CO的生成速率为2.74 μmol‧g^-1‧h^-1，是未引入PVP制备的BiOBr（0.81 μmol‧g^-1‧h^-1）的3.38倍。

关键词: 光催化, 二氧化碳, 一氧化碳, 形貌, BiOBr