Department of Electronic Engineering, Hanyang University, Seoul, 04763, South Korea.
Department of Electronic Engineering, Hanyang University, Seoul, 04763, South Korea; Division of Nanoscale Semiconductor Engineering, Hanyang University, Seoul, 04763, Republic of Korea.
Environ Pollut. 2023 Jan 1;316(Pt 1):120353. doi: 10.1016/j.envpol.2022.120353. Epub 2022 Oct 11.
Partial phase modification of zinc hydroxystannate (ZHS) is an effective technique for improving its light absorption capacity. In this study, a zinc hydroxystannate/zinc-tin oxide (ZHS/ZTO) heterostructure was synthesized via chemical co-precipitation followed by annealing. The as-prepared heterostructure revealed cubic crystal morphology along with high-intensity diffraction peaks in the XRD pattern. The XPS analysis of ZHS/ZTO heterostructures demonstrated the presence of key elements (Zn, Sn, and O) in their most stable ionic forms. The photocatalytic degradation efficiencies of the prepared samples were tested against methyl orange (MO) and tetracycline (TC) in an aqueous medium under UVC (254 nm) radiation. Under optimized conditions, maximum degradation efficiencies of 99% for MO and 97% for TC were observed in 120 and 180 min, respectively. Further, the predominant role of OH˙ radicals in the photocatalytic removal of MO and TC was evident through scavenging experiments. 2nd order kinetic model was outperformed in simulating the degradation mechanism of both targets over 1st and zero-order kinetic models. Finally, a photocatalytic degradation mechanism is proposed based on the energy values estimated for the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) using UPS analysis.
锌锡氢氧化物（ZHS）的部分相改性是提高其光吸收能力的有效方法。在这项研究中，通过化学共沉淀法随后进行退火，合成了锌锡氢氧化物/氧化锡锌（ZHS/ZTO）异质结构。所制备的异质结构具有立方晶体形态，并且在 XRD 图谱中具有高强度衍射峰。ZHS/ZTO 异质结构的 XPS 分析表明，其最稳定的离子形式存在关键元素（Zn、Sn 和 O）。在 UVC（254nm）辐射下，在水介质中对所制备的样品进行了针对甲基橙（MO）和四环素（TC）的光催化降解效率测试。在优化条件下，MO 和 TC 的最大降解效率分别为 99%和 97%，分别在 120 和 180min 内观察到。此外，通过清除实验证明了 OH˙自由基在 MO 和 TC 的光催化去除中的主要作用。2 级动力学模型在模拟两种目标的降解机制方面优于 1 级和 0 级动力学模型。最后，根据 UPS 分析估算的最高占据分子轨道（HOMO）和最低未占据分子轨道（LUMO）的能量值，提出了一种光催化降解机制。
