Defect engineering over Co3O4 catalyst for surface lattice oxygen activation and boosted propane total oxidation

Abstract

Developing efficient and stable catalyst is crucial for the catalytic removal of volatile organic compounds (VOCs). Herein, we report an effective and versatile surface defect engineering for regulation of surface lattice oxygen species in Co3O4 catalyst by alkaline-earth metal doping-etching strategy. The as-synthesized Ca-Co3O4-Ac exhibited remarkable catalytic activity and stability in propane oxidation, with high propane oxidation rate (5.65 × 10−7 mol g−1 s−1) and turnover frequency (TOF, 2.12 × 10−3 s−1) at 210 °C. Simultaneously, the doping-etching strategy could increase the specific surface area, low-temperature reducibility, and oxygen mobility of Co3O4 catalyst. In addition, in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS), density function theory (DFT) calculation, and propane temperature-programmed desorption/surface reaction (C3H8-TPD/TPSR) further revealed that active lattice oxygen species induced by doping-etching strategy promoted the propane activation on the catalyst surface. This work offers a deeper understanding of the reactive oxygen species and provides a feasible strategy for the design of efficient catalysts for practical VOCs removal.