Surface exposure engineering on LaMnO3@Co2MnO4 for high-efficiency ethane catalytic combustion

Abstract

Higher specific surface area and abundant surface oxygen vacancies are considered to be essential to the catalytic combustion. Herein, we elaborately fabricated an innovative catalyst on the basis of LaMnO3@Co2MnO4 under a controllable selective dissolution (SD) treatment for ethane catalytic combustion. La element in perovskite could effectively protect the spinel system as a sacrifice, with MnO2 covering on the spinel surface, thereby enhancing the activity and stability. In combination with XPS, in-situ DRIFT and various characterization results, this acid corrosion could provide induce better reducibility, larger specific surface area, higher Mn4+ and Co3+content and more oxygen vacancies, which played a significant role in promoting the adsorption, activation and decomposition of ethane. Among all as-prepared catalysts, the optimal performance for catalytic ethane combustion was achieved on LMO@CMO-10 catalyst. The T90 of LMO@CMO-10 was 341 °C under space velocity of 80,000 mL·g−1·h−1. This work not only fabricated the catalyst system with higher specific surface area and more oxygen vacancy by SD method, but also provided a potential strategy for the preparation of highly active catalysts.