Jayeola Kehinde D, Sipuka Dimpo S, Sebokolodi Tsholofelo I, Babalola Jonathan O, Zhao Yumeng, Arotiba Omotayo A
Department of Chemical Sciences, University of Johannesburg Doornfontein Johannesburg South Africa
Centre for Nanomaterials Science Research, University of Johannesburg South Africa.
RSC Adv. 2025 Aug 21;15(36):29680-29691. doi: 10.1039/d5ra03795f. eCollection 2025 Aug 18.
This study presents the design of a 2D/1D BiOBr/BiOS p-n heterojunction developed for the degradation of organic pollutants in water, addressing the issue of water contamination caused by pharmaceutical compounds. In an hydrothermal synthesis method, the BiOBr nanosheets were synthesised on BiOS nanorods in varying ratio to form a heterojunction that maximises charge separation and suppressed charge recombination. At an optimal 20% BiOS ratio, BiOBr/BiOS heterojunction achieved 88% degradation efficiency of ciprofloxacin and TOC removal of 60%, when compared with the pristine BiOBr and BiOS. The wider application of the photoanode was investigated by degrading other pollutants like tetracycline and sulfamethoxazole. Comprehensive structural, optical, and electrochemical analyses confirmed the increased surface area and active sites, enhanced light properties and better charged separation. The radical trapping studies identified the hydroxyl radical as a primary contributor to the degradation process, indication the p-n heterojunction facilitated by the formation of a space charge region. This study establishes the BiOBr/BiOS as an effective photoanode for PEC water treatment and provides a promising approach to mitigate organic pollutant detection in water.
本研究展示了一种为降解水中有机污染物而开发的二维/一维BiOBr/BiOS p-n异质结的设计，解决了药物化合物造成的水污染问题。在水热合成法中，BiOBr纳米片以不同比例在BiOS纳米棒上合成，形成一个能使电荷分离最大化并抑制电荷复合的异质结。在最佳的20% BiOS比例下，与原始的BiOBr和BiOS相比，BiOBr/BiOS异质结对环丙沙星的降解效率达到88%，总有机碳去除率为60%。通过降解四环素和磺胺甲恶唑等其他污染物，对光阳极的更广泛应用进行了研究。全面的结构、光学和电化学分析证实了表面积和活性位点的增加、光性能的增强以及更好的电荷分离。自由基捕获研究确定羟基自由基是降解过程的主要贡献者，表明由空间电荷区形成促进的p-n异质结。本研究确立了BiOBr/BiOS作为一种用于光电化学水处理的有效光阳极，并提供了一种减轻水中有机污染物检测的有前景的方法。
