Applied Chemistry Research Laboratory, Department of Chemistry, Faculty of Science, University of Zanjan, Zanjan, Iran.
Applied Chemistry Research Laboratory, Department of Chemistry, Faculty of Science, University of Zanjan, Zanjan, Iran.
Ultrason Sonochem. 2019 Nov;58:104632. doi: 10.1016/j.ultsonch.2019.104632. Epub 2019 Jun 8.
In this research, a series of CuZnTi-LDHs with different Cu/Zn molar ratio were synthesized by co-precipitation method with the purpose of improving the sonocatalytic performance of ZnTi-LDH. All the LDH samples were synthesized by a facile co-precipitation process. The as-prepared LDHs were characterized by Powder X-ray diffraction (XRD), Field emission-scanning electron microscopy (FESEM), Transition electron microscopy (TEM), Brunauer-Emmelt-Teller (BET) analysis, and UV-visible diffuse reflectance spectroscopy (DRS) analysis. The results showed that Cu substitution can significantly enhance the sonocatalytic properties of ZnTi-LDH. The Methylene blue degradation percentage over ZnTi-LDH reached 30% in 90 min, whilst this percentage reaches 71% over CuZnTi-LDH (1:1). The role of the Cu incorporation on the observed enhancement in sonocatalytic performance was revealed by investigating the effect of radical scavengers on degradation efficiency and DRS spectra of ZnTi-LDH and CuZnTi-LDH (1:1). Benzoquinone (BQ), ammonium oxalate and tert-Bu lead to 22.5%, 53.5% and 74.6% decrease in degradation percentage by CuZnTi-LDH (1:1). However, the degradation efficiency showed 16.6%, 3.3% and 63.3% reduction in the presence of BQ, ammonium oxalate and tert-Bu respectively, in dye degradation by ZnTi-LDH. DRS spectra demonstrated that the band gap of the LDH decreases by Cu substitution. The effect of operational parameters on sonodegradation was investigated as well. The kinetics of sonodegradation reaction obeyed the first order reaction kinetics with R of 0.95.
在这项研究中，通过共沉淀法合成了一系列不同 Cu/Zn 摩尔比的 CuZnTi-LDH，目的是提高 ZnTi-LDH 的超声催化性能。所有 LDH 样品均通过简便的共沉淀法合成。所制备的 LDH 采用粉末 X 射线衍射（XRD）、场发射扫描电子显微镜（FESEM）、透射电子显微镜（TEM）、Brunauer-Emmett-Teller（BET）分析和紫外可见漫反射光谱（DRS）分析进行了表征。结果表明，Cu 取代可以显著提高 ZnTi-LDH 的超声催化性能。ZnTi-LDH 在 90 分钟内亚甲蓝的降解率达到 30%，而 CuZnTi-LDH（1:1）的降解率达到 71%。通过研究自由基清除剂对 ZnTi-LDH 和 CuZnTi-LDH（1:1）的降解效率和 DRS 光谱的影响，揭示了 Cu 掺入对观察到的超声催化性能增强的作用。苯醌（BQ）、草酸铵和叔丁基导致 CuZnTi-LDH（1:1）的降解率分别下降 22.5%、53.5%和 74.6%。然而，在存在 BQ、草酸铵和叔丁基的情况下，ZnTi-LDH 降解时，降解效率分别降低了 16.6%、3.3%和 63.3%。DRS 光谱表明，LDH 的带隙通过 Cu 取代而降低。还研究了操作参数对超声降解的影响。超声降解反应动力学符合一级反应动力学，R 为 0.95。
