PDF(Pubmed)
Abstract：
Rhodamine B (RhB) is a harmful dye released by industrial wastewaters, thus necessitating its urgent removal. Advanced oxidation processes constitute promising strategies to purify polluted water. Among others, photocatalysis relies on reactive oxygen species (ROS) produced by photocatalytic particles, typically semiconductors like titania or zinc oxide (ZnO), excited by solar or UV-Vis light. However, their wide band gap limits their catalytic capabilities within the absorption of the UV spectrum and causes fast electron-hole recombination. This study presents novel strategies to overcome these limitations: (i) doping semiconductors to increase photocatalytic efficiency; (ii) sensitization-mediated photocatalysis for visible light activation using chemical moieties to trap dye molecules; (iii) nanosizing the photocatalysts to enhance the surface area. ZnO nanoparticles, doped with iron or gadolinium and capped with oleic acid are here synthesized and tested in RhB dye solutions. Remarkably, the results demonstrate an ultra-fast RhB degradation, driven by oleic acid having crucial role in dye adsorption. The degradation mechanisms, including ROS-induced N-deethylation and xanthene group cleavage, are also unraveled. These findings underscore the efficacy of the proposed semiconductor photocatalyst design, highlighting a significant advancement with extensive potential applications in wastewater remediation. This innovative approach paves the way for more efficient and practical solutions to combat industrial dye pollution.
摘要：
罗丹明B（RhB）是工业废水释放的有害染料，因此，有必要将其紧急删除。高级氧化工艺构成了净化污水的有希望的策略。其中,光催化依赖于光催化颗粒产生的活性氧（ROS），通常是二氧化钛或氧化锌(ZnO)等半导体，由太阳能或UV-Vis光激发。然而,它们的宽带隙限制了它们在紫外光谱吸收范围内的催化能力，并导致快速的电子-空穴复合。本研究提出了克服这些限制的新策略:(i)掺杂半导体以提高光催化效率;(ii)使用化学部分捕获染料分子的用于可见光活化的敏化介导的光催化;(iii)纳米化光催化剂以增强表面积。ZnO纳米颗粒,这里合成了铁或钆掺杂并用油酸封端，并在RhB染料溶液中进行了测试。值得注意的是,结果表明RhB超快降解，由油酸驱动，在染料吸附中起关键作用。降解机制，包括ROS诱导的N-去乙基化和黄吨基团裂解，也被解开了。这些发现强调了所提出的半导体光催化剂设计的功效，突出了在废水修复中具有广泛潜在应用的重大进展。这种创新方法为更有效和实用的解决方案铺平了道路，以对抗工业染料污染。
