Enhanced Low-Temperature Photothermal Combustion of C3H8 Using Surface-Engineered Co3O4 Nanocatalysts

Abstract

Propane (C₃H₈), a challenging volatile organic compound (VOC), faces limitations in catalytic combustion due to high ignition temperatures and catalyst deactivation. Photothermal catalytic combustion for C3H8, an innovative catalysis approach, significantly improves the low-temperature purification efficiency of catalysts but is limited by the band structure. This study addresses these issues by developing a photothermal Co₃O₄-HT catalyst through hydrothermal synthesis, achieving breakthrough low-temperature oxidation performance (T₅₀ <160 °C) under illumination. Key mechanistic insights reveal that the narrow bandgap and enhanced surface photocurrent of Co₃O₄-HT facilitate efficient charge separation, while light irradiation synergistically accelerates lattice oxygen release via the Mars-van Krevelen (MvK) mechanism and promotes gas-phase oxygen activation. Crucially, photogenerated active oxygen species strengthen C₃H₈ adsorption and rapidly degrade carboxylate/carbonyl intermediates, overcoming conventional kinetic limitations. This work establishes a dual-functional catalytic strategy that integrates photonic energy utilization with thermal activation, providing a universal framework for designing high-efficiency VOC oxidation systems. The demonstrated synergy between band gap engineering and reaction pathway optimization opens new avenues for sustainable air pollution control technologies.