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The properties of LaCoO 3 are modified by a controllable P doping strategy via a simple sol−gel route. It is demonstrated that appropriate P doping is beneficial for forming a relatively pure perovskite phase and hinders the growth of perovskite nanoparticles. The combined results of density functional theory (DFT), extended X-ray absorption fine structure (EXAFS), X-ray absorption near-edge structure (XANES), temperature-programmed reduction of hydrogen (H 2 -TPR), Xray photoelectron spectroscopy (XPS), and temperature-programmed desorption of ammonia (NH 3 -TPD) reveal that appropriate P doping gives rise to more oxygen vacancies, optimized distribution of Co ions, and improved surface acidity, which are beneficial for the adsorption of active oxygen species and the activation of propane molecules, resulting in an excellent catalytic oxidation performance. Especially, LaCo 0.97 P 0.03 O 3 exhibits more surface-active oxygen species, higher bulk Co 3+ proportion, increased surface Co 2+ species, and increased acidity, resulting in its superior propane oxidation performance, which is dominated by the Langmuir−Hinshelwood mechanism. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) confirms that the presence of P will accelerate oxygen mobility, which in turn promotes the oxidation rate. Moreover, the obtained LaCo 0.97 P 0.03 O 3 catalyst displays excellent thermal stability during the 60 h durability test at 400 °C and strong resistance against 5 vol % H 2 O and/or 5 vol % CO 2 for prolonged 150 h.

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Mn–Co–O catalysts with different Mn/Co molar ratios were synthesized by means of a facile inverse coprecipitation strategy and applied for the oxidation of propane (C3H8). The XRD pattern of Co2Mn1Oδ (molar ratio of Mn:Co = 1:2) indicates a Co3O4 phase, and most Mn incorporates into Co3O4 lattice to form a solid solution. Minor distributed Mn species occur structure reforming, totally converting to a stable Co–Mn solid solution during oxidation process. Meanwhile, Co2Mn1Oδ features a porous core–shell morphology, the core and shell of which are made up of Co–Mn solid solution, giving rise to a high surface area. The optimized synergistic effect of manganese and cobalt improves low temperature reducibility and produces rich surface active Co3+ species and surface-absorbed oxygen over Co2Mn1Oδ. As a result, it exhibits a prominent excellent catalytic activity, and delivers good thermal stability in the presence of 5 vol % H2O and 5 vol % CO2. In situ DRIFTs analysis displays the reaction path of C3H8 over Co2Mn1Oδ, where dominate intermediate species formate are easily decomposed into CO2. The synthesized porous core–shell Mn–Co–O can be a promising candidate replacing non-noble catalysts toward C3H8 oxidation at low temperature.

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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Summary of main observation and conclusionA series of electrospun LaCoO3 perovskites derived from CoX2 (X = CH3COO–, NO3–) were prepared and investigated for total propane oxidation. It is shown that pure rhombohedral perovskite LaCoO3 from Co(CH3COO)2 can be obtained at a relatively low temperature, 400 °C, benefitting from the complexation effect of CH3COO–. On the other hand, CH3COO– can accelerate the complete decomposition of polymer. The low‐temperature process can protect LaCoO3 nanoparticles from growing up. As a result, Co(CH3COO)2‐derived catalysts exhibit better propane oxidation activity than the ones suffered the same thermal treatment by using Co(NO3)2. XPS and H2‐TPR analysis provide that there is subtle change in Co3+/Co2+ on bulk/surface of Co(CH3COO)2‐derived catalysts prepared at different temperatures, giving rise to similar propane oxidation activities. Moreover, the result of cyclic stability test over 400 °C obtained catalyst shows little deactivation, demonstrating a good thermal stability. Our study can provide a feasible route for energy‐saving synthesis of LaCoO3 catalyst applied in the catalytic oxidation of volatile organic compounds (VOCs).