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 (C3H8) 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 C3H8 molecules, are enriched. As a result, the LCB‐7 (molar ratio of Co/B=0.93:0.07) displays the best C3H8 oxidation activity. Simultaneously, the above catalyst exhibits superior thermal stability against CO2 and H2O, 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.

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In the oxidation reaction of volatile organic compounds catalyzed by metal oxides, distinguishing the role of active metal sites and oxygen mobility at specific preferentially exposed crystal planes and diverse temperatures is challenging. Herein, Co3O4 catalysts with four different preferentially exposed crystal planes [(220), (222), (311), and (422)] and oxygen vacancy formation energies were synthesized and evaluated in styrene complete oxidation. It is demonstrated that the Co3O4 sheet (Co3O4–I) presents the highest C8H8 catalytic oxidation activity (R 250 °C = 8.26 μmol g–1 s–1 and WHSV = 120,000 mL h–1 g–1). Density functional theory studies reveal that it is difficult for the (311) and (222) crystal planes to form oxygen vacancies, but the (222) crystal plane is the most favorable for C8H8 adsorption regardless of the presence of oxygen vacancies. The combined analysis of temperature-programmed desorption and temperature-programmed surface reaction of C8H8 proves that Co3O4–I possesses the best C8H8 oxidation ability. It is proposed that specific surface area is vital at low temperature (below 250 °C) because it is related to the amount of surface-adsorbed oxygen species and low-temperature reducibility, while the ratio of surface Co3+/Co2+ plays a decisive role at higher temperature because of facile lattice oxygen mobility. In situ diffuse reflectance infrared Fourier spectroscopy and the 18O2 isotope experiment demonstrate that C8H8 oxidation over Co3O4–I, Co3O4–S, Co3O4–C, and Co3O4–F is mainly dominated by the Mars–van Krevelen mechanism. Furthermore, Co3O4–I shows superior thermal stability (57 h) and water resistance (1, 3, and 5 vol % H2O), which has the potential to be conducted in the actual industrial application.

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