Synthesis and Photocatalytic Activity of Pt-Deposited TiO2 Nanotubes (TNT) for Rhodamine B Degradation

Xiaojian Qiu; Zhenning Wan; Mengjie Pu; Xiuru Xu; Yuanyao Ye; Chunhua Hu

doi:10.3389/fchem.2022.922701

Synthesis and Photocatalytic Activity of Pt-Deposited TiO₂ Nanotubes (TNT) for Rhodamine B Degradation

Front Chem. 2022 May 31:10:922701. doi: 10.3389/fchem.2022.922701. eCollection 2022.

Authors

Xiaojian Qiu¹, Zhenning Wan², Mengjie Pu², Xiuru Xu³, Yuanyao Ye⁴, Chunhua Hu¹

Affiliations

¹ School of Resources and Environment, Nanchang University, Nanchang, China.
² College of Life and Environmental Science, Wenzhou University, Wenzhou, China.
³ School of Agricultural and Biological Technology, Wenzhou Vocational College of Science and Technology, Zhejiang, China.
⁴ School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, China.

Abstract

Dye wastewater has attracted more and more attention because of its high environmental risk. In this study, a novel TiO₂ nanotube (TNT) catalyst was prepared and its morphology and structure were characterized. The synthetic catalyst was used to degrade Rhodamine B (RhB) under UV light and evaluated for the application performance. According to the characterization results and degradation properties, the optimum synthetic conditions were selected as 400°C calcination temperature and 10 wt% Pt deposition. As a result, the degradation efficacies were sequenced as TNT-400-Pt > TNT-500-Pt > TNT-400 > TNT-300-Pt. In addition, the effect of pH and initial concentration of RhB were explored, and their values were both increased with the decreased degradation efficacy. While the moderate volume of 11 mm of H₂O₂ addition owned better performance than that of 0, 6, and 15 mm. Scavengers such as tertbutanol (t-BuOH), disodium ethylenediaminetetraacetate (EDTA-Na₂), and nitroblue tetrazolium (NBT) were added during the catalytic process and it proved that superoxide radical anions $(O_{2}^{- •})$ , photogenerated hole (h⁺) and hydroxyl radical (OH•) were the main active species contributing for RhB removal. For the application, TNT-Pt could deal with almost 100% RhB, Orange G (OG), Methylene blue (MB), and Congo red (CR) within 70 min and still kept more than 50% RhB removal in the fifth recycling use. Therefore, TNT-Pt synthesized in this study is potential to be applied to the dye wastewater treatment.

Keywords: Rh B; TNT-Pt; morphology and structure; photocatalysis; superoxide radical anions.