Department of Chemical Sciences, University of Johannesburg, Johannesburg, South Africa.
Centre for Nanomaterials Science Research, University of Johannesburg, Johannesburg, South Africa.
Sci Rep. 2022 Mar 10;12(1):4214. doi: 10.1038/s41598-022-08213-0.
We report the photoelectrocatalysis of diclofenac sodium using a reactor consisting of Ag-BiVO/BiOI anode and Ag-BiOI cathode. The electrodes were prepared through electrodeposition on FTO glass and modified with Ag nanoparticles through photodeposition. The structural and morphological studies were carried out using XRD, SEM, and EDS which confirmed the successful preparation of the materials. The optical properties as observed with UV-DRS revealed that the electrodes were visible light active and incorporation of metallic Ag particles on the surface increased the absorption in the visible light region. Presence of p-n heterojunction in the anode led to decrease in the spontaneous recombination of photoexcited electron-hole pairs as seen in the photocurrent response. The results from photoelectrocatalytic degradation experiments revealed that replacing platinum sheet with Ag-BiOI as counter electrode resulted in higher (92%) and faster removal of diclofenac sodium as evident in the values of apparent rate constants. The reaction mechanism further revealed that efficiently separated photogenerated holes played a major role in the degradation of the pharmaceutical. The prepared electrodes showed good stability and impressive reusability. The reports from this study revealed that the dual photoelectrodes system has a great potential in treating pharmaceutical polluted wastewater using visible light irradiation.
我们报告了使用由 Ag-BiVO/BiOI 阳极和 Ag-BiOI 阴极组成的反应器对双氯芬酸钠进行光电催化。通过在 FTO 玻璃上电沉积和通过光沉积在 Ag 纳米颗粒上修饰制备了电极。通过 XRD、SEM 和 EDS 进行了结构和形态研究，证实了材料的成功制备。通过紫外可见漫反射光谱观察到的光学性质表明，电极具有可见光活性，表面上金属 Ag 颗粒的掺入增加了可见光区域的吸收。阳极中存在 p-n 异质结导致光激发电子-空穴对的自发复合减少，如在光电流响应中所见。光电催化降解实验的结果表明，用 Ag-BiOI 代替铂片作为对电极可以实现更高（92%）和更快地去除双氯芬酸钠，这从表观速率常数的值中可以明显看出。反应机理进一步表明，有效地分离光生空穴在药物降解中起主要作用。所制备的电极表现出良好的稳定性和令人印象深刻的可重复使用性。该研究的报告表明，双光电电极系统在使用可见光照射处理药物污染废水方面具有巨大的潜力。
