Channei Duangdao, Nakaruk Auppatham, Phanichphant Sukon
Department of Chemistry, Faculty of Science, Naresuan University, Phitsanulok 65000, Thailand; Research Center for Academic Excellence in Petroleum, Petrochemicals and Advanced Materials, Naresuan University, Phitsanulok 65000, Thailand.
Department of Industrial Engineering, Faculty of Engineering, Naresuan University, Phitsanulok 65000, Thailand; Centre of Excellence for Innovation and Technology for Water Treatment, Naresuan University, Phitsanulok 65000, Thailand.
Spectrochim Acta A Mol Biomol Spectrosc. 2017 Aug 5;183:218-224. doi: 10.1016/j.saa.2017.04.063. Epub 2017 Apr 22.
The main task of the present work is to enhance the photocatalytic degradation efficiency of methylene blue (MB) by using CeO/sugarcane bagasse (SCB) composite catalysts. Homogeneous precipitation method was used to synthesis CeO-SCB composite catalysts by adding SCB powder to precursor solution of Ce base-metal. The structural analytical data indicated the pure cubic fluorite structure of CeO. Morphological images revealed the coating of CeO layer on high surface area of SCB core-shell. The chemical analysis presented spectrum of the Ce 3d in CeO/SCB sample existed in the form of the Ce and Ce mixed- valence states. Optical spectra showed the shift of absorption edge towards longer visible region upon supporting CeO with SCB. The main chemical composition of the SCB was K, Ca, and Si. Furthermore, recombination of the photogenerated electrons and holes was identified by photoluminescence techniques (PL), the data suggested inhibition of electron-hole pairs recombination by the cations from SCB loaded in CeO/SCB composite. Photocatalytic activity of CeO/SCB catalyst was investigated via the degradation of MB under UV-A irradiation. Experimental kinetic data followed the pseudo-first order model. CeO supported with SCB adsorbent had higher photocatalytic activity in dye wastewater treatment compared to the pure CeO. The proposed mechanism explaining the high photocatalytic efficiency of CeO/SCB was associated with high surface properties and the suppression of recombination of the photogenerated electron-hole pairs by the SCB adsorbent.
本工作的主要任务是通过使用CeO/甘蔗渣（SCB）复合催化剂来提高亚甲基蓝（MB）的光催化降解效率。采用均匀沉淀法，将SCB粉末加入到Ce基金属前驱体溶液中合成CeO-SCB复合催化剂。结构分析数据表明CeO具有纯立方萤石结构。形态图像显示在SCB核壳的高表面积上有CeO层的包覆。化学分析表明，CeO/SCB样品中Ce 3d的光谱以Ce和Ce混合价态的形式存在。光谱表明，当用SCB负载CeO时，吸收边向更长的可见光区域移动。SCB的主要化学成分是K、Ca和Si。此外，通过光致发光技术（PL）确定了光生电子和空穴的复合，数据表明负载在CeO/SCB复合材料中的SCB阳离子抑制了电子-空穴对的复合。通过在UV-A照射下MB的降解研究了CeO/SCB催化剂的光催化活性。实验动力学数据符合准一级模型。与纯CeO相比，负载SCB吸附剂的CeO在染料废水处理中具有更高的光催化活性。所提出的解释CeO/SCB高光催化效率的机理与高表面性质以及SCB吸附剂对光生电子-空穴对复合的抑制有关。
