Shoneye Ayoola, Jiao Haimiao, Tang Junwang
Department of Chemical Engineering University College London Torrington Place, London, WC1E 7JE, U.K.
J Phys Chem C Nanomater Interfaces. 2023 Jan 17;127(3):1388-1396. doi: 10.1021/acs.jpcc.2c06796. eCollection 2023 Jan 26.
A series of monometallic and bimetallic cocatalyst(s), comprising FeO , CuO , CoO , FeO -CuO , and FeO -CoO loaded TiO catalysts prepared by the surface impregnation method, were investigated for the photocatalytic mineralization of the widely used four herbicides: 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP), 2,4-dichlorophenoxyacetic acid (2,4-D), and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T). It was found that FeO -CoO /TiO showed the highest photocatalytic efficiency toward mineralization of selected herbicides. FeO -CoO /TiO achieves 92% TOC removal in 180 min, representing nearly three time activity of the benchmark PC50 TiO. From XPS analysis, FeOOH, CuO, and CoO were determined to be loaded onto the TiO surface. The outstanding photocatalytic performance of the optimized FeO -CoO /TiO sample for herbicides mineralization is due to an increased charge separation and enhanced hydroxyl radicals production monitored by diverse spectroscopies. Based on the proposed charge transfer mechanism, FeO -CoO cocatalyst species accelerate the transfer of photogenerated holes on TiO, thus facilitating hydroxyl radicals production.
通过表面浸渍法制备了一系列负载有FeO 、CuO 、CoO 、FeO -CuO 和FeO -CoO 的单金属和双金属助催化剂的TiO催化剂，用于光催化矿化四种广泛使用的除草剂：2,4-二氯苯酚（2,4-DCP）、2,4,6-三氯苯酚（2,4,6-TCP）、2,4-二氯苯氧基乙酸（2,4-D）和2,4,5-三氯苯氧基乙酸（2,4,5-T）。结果发现，FeO -CoO /TiO对所选除草剂的矿化表现出最高的光催化效率。FeO -CoO /TiO在180分钟内实现了92%的总有机碳去除率，几乎是基准PC50 TiO活性的三倍。通过XPS分析确定，FeOOH、CuO和CoO负载在TiO表面。优化后的FeO -CoO /TiO样品对除草剂矿化具有出色的光催化性能，这归因于通过多种光谱监测到的电荷分离增加和羟基自由基生成增强。基于所提出的电荷转移机制，FeO -CoO 助催化剂物种加速了TiO上光生空穴的转移，从而促进了羟基自由基的生成。
