一步法直接合成rGO/Bi2O2CO3及其光催化性能研究

采用简单易行的一锅水热法, 制备了还原氧化石墨烯(RGO)复合的Bi₂O₂CO₃光催化剂。通过XRD、N₂吸附、XPS、SEM和TEM等测试手段对光催化剂进行表征。结果表明: 石墨烯与Bi₂O₂CO₃纳米片形成了有效复合。在设计吸附饱和排除RGO物理吸附的影响下, 发现复合光催化剂的性能明显提高, 其中RGO复合量为6.0wt%时活性最佳, 其光催化降解RhB的速率是Bi₂O₂CO₃的3.02倍, 并具有良好的循环稳定性。光电谱学分析表明复合RGO有效抑制了光生电子-空穴对的复合, 且拓宽和增强了催化剂的可见光吸收。机理分析表明: RGO/Bi₂O₂CO₃中O₂可多位点捕获光生电子, 从而产生更多活性物种O₂^-·, 实现对污染物的快速有效降解。

RGO/Bi2O2CO3: One-step Synthesis and Photocatalytic Property

RGO/Bi₂O₂CO₃ photocatalyst was prepared by one-pot hydrothermal method. The samples were characterized by XRD, N₂ adsorption, XPS, SEM, and TEM. The results indicate that Bi₂O₂CO₃ are effectively composited by the reduced graphene oxide (RGO). The photocatalytic property of RGO/Bi₂O₂CO₃ composite is obviously improved after exclusion of physical adsorption from graphene. Specifically, the sample composited by 6.0wt% RGO shows the best photocatalytic activity with a rate constant as fast as 3.02-folds of Bi₂O₂CO₃ for degradation of RhB. Photoelectrochemical analysis indicate that the introduction of RGO effectively inhibits the recombination of photogenerated e^-/h⁺ pairs and broadens the visible light absorption of Bi₂O₂CO₃. Mechanism exploration shows that more active species O₂^-· is produced due to the multi-site electron capture of O₂ in the composite.