Amorphous Boron Dispersed in LaCoO3 with Large Oxygen Vacancies for Efficient Catalytic Propane Oxidation

Chemistry. 2021 Mar 8;27(14):4738-4745. doi: 10.1002/chem.202004848. Epub 2021 Feb 3.

Abstract

Unsatisfactory oxygen mobility is a considerable barrier to the development of perovskites for low-temperature volatile organic compounds (VOCs) oxidation. This work introduced small amounts of dispersed non-metal boron into the LaCoO3 crystal through an easy sol-gel method to create more oxygen defects, which are conducive to the catalytic performance of propane (C3 H8 ) oxidation. It reveals that moderate addition of boron successfully induces a high distortion of the LaCoO3 crystal, decreases the perovskite particle size, and produces a large proportion of bulk Co2+ species corresponding to abundant oxygen vacancies. Additionally, surface Co3+ species, as the acid sites, which are active for cleaving the C-H bonds of C3 H8 molecules, are enriched. As a result, the LCB-7 (molar ratio of Co/B=0.93:0.07) displays the best C3 H8 oxidation activity. Simultaneously, the above catalyst exhibits superior thermal stability against CO2 and H2 O, lasting 200 h. This work provides a new strategy for modifying the catalytic VOCs oxidation performance of perovskites by the regulation of amorphous boron dispersion.

Keywords: LaCoO3; amorphous boron dispersion; catalytic propane oxidation; durability; oxygen vacancies.