Surface oxygen vacancy-dependent molecular oxygen activation for propane combustion over α-MnO2

Huayu Gu; Jintong Lan; Haolu Hu; Falong Jia; Zhihui Ai; Lizhi Zhang; Xiao Liu

doi:10.1016/j.jhazmat.2023.132499

Surface oxygen vacancy-dependent molecular oxygen activation for propane combustion over α-MnO₂

J Hazard Mater. 2023 Oct 15:460:132499. doi: 10.1016/j.jhazmat.2023.132499. Epub 2023 Sep 6.

Authors

Huayu Gu¹, Jintong Lan¹, Haolu Hu¹, Falong Jia¹, Zhihui Ai¹, Lizhi Zhang², Xiao Liu³

Affiliations

¹ Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, PR China.
² Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, PR China; School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China.
³ Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, PR China. Electronic address: liuxiao71@ccnu.edu.cn.

PMID: 37683342
DOI: 10.1016/j.jhazmat.2023.132499

Abstract

Oxygen vacancies (O_V), as the sites of molecular oxygen adsorption and activation, play an important role in the catalytic combustion process of volatile organic compounds (VOCs). Revealing the relationship between O_V concentration and molecular oxygen activation behavior is of significance to construct the efficient catalysts. Herein, α-MnO₂ with different O_V concentrations was prepared to investigate the molecular oxygen activation for C₃H₈ combustion. It is disclosed that the enhanced O_V concentration in α-MnO₂ induced the reconfiguration of surface metal atoms, resulting in the transformation of oxygen activation configuration from end-on mode to side-on mode. Oxygen molecules in side-on mode possessed more localized electron density and weaker coordination bond strength with surrounding Mn atoms, which were more favorable to adsorb C₃H₈ molecules and activate C-H bond for the improved combustion performance. This work provides a new understanding to reveal that the increased O_V concentration contributes to more efficient VOCs combustion.

Keywords: Adsorption configuration; Molecular oxygen activation; Oxygen vacancy; Propane combustion; α-MnO(2).