Perovskite oxides are highly promising catalysts for the combustion removal of volatile organic compounds (VOCs) due to their excellent stability, structural flexibility, and compositional versatility. This study presents a novel perovskite oxide that exhibits enhanced catalytic activity and superior durability for toluene combustion at reduced temperatures. This improvement is achieved by phosphorus doping at the B-site of LaCoO_3-δ (LC) perovskite oxide, followed by post-synthesis acid etching for a proper time. The resulting catalyst demonstrates increased specific surface area, higher total pore volume, and enhanced oxygen vacancy concentration both in the bulk and on the surface. Additionally, the activity of surface lattice oxygen species is significantly improved, leading to enhanced catalytic performance in toluene combustion. Notably, the optimized catalyst shows an exceptionally low activation energy (E_a) of 49.3 kJ mol⁻¹, with a T₉₀ reduction of over 214 ℃ compared to the phosphorus doped LC and 190 ℃ compared to pristine LC. Phosphorus doping plays a main role in significantly improving the long-term durability, particularly in the presence of CO₂ and H₂O, while acid etching boosts the catalytic activity. This work introduces a rational and innovative strategy for optimizing VOC oxidation by improving the structure and surface chemical states of perovskite catalysts.

For protonic ceramic fuel cells, it is key to develop material with high intrinsic activity for oxygen activation and bulk proton conductivity enabling water formation at entire electrode surface. However, a higher water content which benefitting for the increasing proton conductivity will not only dilute the oxygen in the gas, but also suppress the O₂ adsorption on the electrode surface. Herein, a new electrode design concept is proposed, that may overcome this dilemma. By introducing a second phase with high-hydrating capability into a conventional cobalt-free perovskite to form a unique nanocomposite electrode, high proton conductivity/concentration can be reached at low water content in atmosphere. In addition, the hydronation creates additional fast proton transport channel along the two-phase interface. As a result, high protonic conductivity is reached, leading to a new breakthrough in performance for proton ceramic fuel cells and electrolysis cells devices among available air electrodes.