Baghdadi Yasmine, Temerov Filipp, Cui Junyi, Daboczi Matyas, Rattner Eduardo, Sena Michael Segundo, Itskou Ioanna, Eslava Salvador
Department of Chemical Engineering and Centre for Processable Electronics, Imperial College London, London SW7 2AZ, United Kingdom.
Nano and molecular system (NANOMO) research unit, University of Oulu, Oulu 90570, Finland.
Chem Mater. 2023 Oct 16;35(20):8607-8620. doi: 10.1021/acs.chemmater.3c01635. eCollection 2023 Oct 24.
Lead-free halide perovskite derivative CsBiBr has recently been found to possess optoelectronic properties suitable for photocatalytic CO reduction reactions to CO. However, further work needs to be performed to boost charge separation for improving the overall efficiency of the photocatalyst. This report demonstrates the synthesis of a hybrid inorganic/organic heterojunction between CsBiBr and g-CN at different ratios, achieved by growing CsBiBr crystals on the surface of g-CN using a straightforward antisolvent crystallization method. The synthesized powders showed enhanced gas-phase photocatalytic CO reduction in the absence of hole scavengers of 14.22 (±1.24) μmol CO g h with 40 wt % CsBiBr compared with 1.89 (±0.72) and 5.58 (±0.14) μmol CO g h for pure g-CN and CsBiBr, respectively. Photoelectrochemical measurements also showed enhanced photocurrent in the 40 wt % CsBiBr composite, demonstrating enhanced charge separation. In addition, stability tests demonstrated structural stability upon the formation of a heterojunction, even after 15 h of illumination. Band structure alignment and selective metal deposition studies indicated the formation of a direct Z-scheme heterojunction between the two semiconductors, which boosted charge separation. These findings support the potential of hybrid organic/inorganic g-CN/CsBiBr Z-scheme photocatalyst for enhanced CO photocatalytic activity and improved stability.
最近发现无铅卤化物钙钛矿衍生物CsBiBr具有适合光催化将CO₂还原为CO的光电特性。然而，需要进一步开展工作以促进电荷分离，从而提高光催化剂的整体效率。本报告展示了通过使用简单的反溶剂结晶法在g-C₃N₄表面生长CsBiBr晶体，合成了不同比例的CsBiBr与g-C₃N₄之间的无机/有机杂化异质结。与纯g-C₃N₄和CsBiBr分别为1.89（±0.72）和5.58（±0.14）μmol CO g⁻¹ h⁻¹相比，所合成的粉末在没有空穴清除剂的情况下，40 wt% CsBiBr的气相光催化CO₂还原性能增强，达到14.22（±1.24）μmol CO g⁻¹ h⁻¹。光电化学测量还表明，40 wt% CsBiBr复合材料中的光电流增强，证明电荷分离得到增强。此外，稳定性测试表明，即使在光照15小时后，形成异质结时结构仍保持稳定。能带结构排列和选择性金属沉积研究表明，两种半导体之间形成了直接的Z型异质结，这促进了电荷分离。这些发现支持了有机/无机g-C₃N₄/CsBiBr Z型杂化光催化剂在增强CO₂光催化活性和提高稳定性方面的潜力。
