Urea-H2O2 defect engineering of δ-MnO2 for propane photothermal oxidation: Structure-activity relationship and synergetic mechanism determination

Chao Feng; Yuxi Bi; Chong Chen; Shuangju Li; Zhong Wang; Hongchuan Xin; Yuan Pan; Fang Liu; Yukun Lu; Yunqi Liu; Runduo Zhang; Xuebing Li

doi:10.1016/j.jcis.2023.03.052

Urea-H₂O₂ defect engineering of δ-MnO₂ for propane photothermal oxidation: Structure-activity relationship and synergetic mechanism determination

J Colloid Interface Sci. 2023 Jul:641:48-58. doi: 10.1016/j.jcis.2023.03.052. Epub 2023 Mar 11.

Authors

Chao Feng¹, Yuxi Bi², Chong Chen², Shuangju Li³, Zhong Wang³, Hongchuan Xin³, Yuan Pan², Fang Liu², Yukun Lu², Yunqi Liu⁴, Runduo Zhang⁵, Xuebing Li⁶

Affiliations

¹ Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China; State Key Laboratory of Heavy Oil Processing, College of Chemical Engineering, China University of Petroleum, Qingdao 266580, China.
² State Key Laboratory of Heavy Oil Processing, College of Chemical Engineering, China University of Petroleum, Qingdao 266580, China.
³ Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China.
⁴ State Key Laboratory of Heavy Oil Processing, College of Chemical Engineering, China University of Petroleum, Qingdao 266580, China. Electronic address: liuyq@upc.edu.cn.
⁵ State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Energy Environmental Catalysis, Beijing University of Chemical Technology, Beijing 100029, China.
⁶ Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China. Electronic address: Lixb@qibebt.ac.cn.

PMID: 36924545
DOI: 10.1016/j.jcis.2023.03.052

Abstract

Photothermal catalysis has an advantage in effective and economical elimination technology of volatile organic compounds (VOCs) in the ascendant. Herein, various surface defect engineering routes were adopted to enhance the low-temperature propane oxidation of δ-MnO₂. Compared to reducing etchants urea and vitamin C, δ-MnO₂ treated with urea - H₂O₂ exhibited an excellent thermal (T₉₀ = 240 ℃) and photothermal (T₉₀ = 196 ℃) activities of propane oxidation. Urea - H₂O₂ treatment provided high concentration of Mn⁴⁺ and surface-active oxygen (Mn⁴⁺-O_sur) species as surface-active sites, and produced numerous oxygen vacancies to improve charge separation and superoxide species generation capacity. Thus, the photothermal conversion efficiency and low-temperature reducibility were remarkably enhanced. Furthermore, the photothermal synergistic catalytic mechanism was proposed based on in-situ diffuse reflectance infrared Fourier transform spectroscopy and control experiments. The strategy here offered insight into the rational design of efficient transition catalysts, and in-depth understanding of the photothermal catalytic VOCs removal mechanism.

Keywords: Defect engineering; Photothermal catalysis; Propane oxidation; Reaction mechanism; δ-MnO(2).