With the rare earth element La was selected as the A site and transition metal ions (Ni, Fe) as the B site of perovskite-type oxides with general formula ABO3, a series of LaNixFe1-xO3 (x=0, 0.3, 0.5, 0.7, 0.8, 1.0) perovskite catalysts were prepared by sol-gel method to investigate their catalytic performance for oxygen evolution reaction (OER). The catalyst activity was screened by linear scanning cyclic voltammetry (LSV), Tafel curves, and electrochemical impedance spectroscopy (EIS). A group of electrochemical tests for LaNixFe1-xO3 with various Ni/Fe ratios indicate that LaNi0.8Fe0.2O3 catalyst exhibits excellent electrochemical activity, with a resistance to charge-transfer reaction (Rct) of 5.942 Ω cm-2, overpotential of 391 mV, a Tafel slope of 102.8 mV dec-1, and electrochemical double-layer capacitance (Cdl) of 12.31 mF cm-1. The stability test after 15000 s proves that the optimized LaNi0.8Fe0.2O3 has better stability compared to pristine LaFeO3 and LaNiO3. In addition, LaNi0.8Fe0.2O3 also exhibits the largest electrochemical active area (ECSA=307.75 cm2) and exchange current density (jo=1.08 mA cm-2). This work provides reference for perovskite in improving oxygen evolution performance.

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A series of LaNixB1-xO3 (B=Co, Cu) perovskite catalysts were prepared by sol-gel method and employed in toluene degradation. The catalysts were characterized by XRD, UV-Vis, SEM and XPS to investigate crystal structure, morphology and composition of the catalyst. The effect of different calcination temperatures and time on the performance of perovskite catalysts for toluene degradation were investigated. And the CO2 selectivity was also carried out on as-prepared catalysts. The results showed that a small amount of Co-doping in B site of LaNiO3 could significantly improve its toluene degradation, while the substitution of Ni with Cu could not effectively enhance its activity. When the Ni/Co molar ratio in LaNixCo1-xO3 perovskite was 3:1, LaNi0.75Co0.25O3 catalyst exhibited the best activity, and it showed relatively short time and low temperature for toluene conversion of 100%. Therefore, LaNi0.75Co0.25O3 catalyst has a broad prospect in the degradation of volatile organic pollutants.