Heterostructured TiO<sub>2</sub>@HKUST-1 for the enhanced removal of methylene blue by integrated adsorption and photocatalytic degradation
Min Xiaobo, Xinyu Li, Jie Zhao, Xiaoxian Hu, Yang Weichun
Abstract
Aiming at exploring an effective photocatalytic adsorbent for organic dye removal, a series of heterostructured TiO2@HKUST-1 photocatalysts, by incorporating HKUST-1 with different TiO2 nanoparticles loading, were prepared by single-step hydrothermal method. The morphology and surface characteristics of the as-prepared TiO2@HKUST-1were analyzed using SEM, HRTEM, XRD, FTIR, UV–vis DRS, and Photoluminescence techniques. The adsorption-photocatalytic degradation of the model dye methylene blue (MB) on the catalysts was investigated. It was indicated that the introduction of a certain amount of TiO2 on the surface of HKUST-1 could improve the transfer and separation of the photogenerated charge carriers, resulting in the enhanced photocatalytic activity. The optimal 0.02TiO2@HKUST-1 exhibited the highest MB removal rate with about 4.4 and 19.3 times as high MB removal efficiency as that of HKUST-1 and TiO2, respectively. Heterostructured TiO2@HKUST-1 materials for the removal of MB involved the integrated adsorption and visible light photocatalysis. Meanwhile, the composite exhibited good reusability in the process of cyclic experiments. Therefore, this work provides a potential MOF-based photocatalytic adsorbent for organic dye removal.