<p>Photothermocatalytic oxidation technology stands out as one of the most environmentally friendly and effective approaches for VOC degradation, and the catalyst plays a pivotal role in this process. In this study, carbon-doped Co₃O₄ nanocomposites (C-Co₃O₄) were synthesized via the sol-gel method and employed for the photothermal degradation of toluene. The results reveal that the calcination temperature profoundly influences the photothermal catalytic performance of the materials. C-Co₃O₄-250, obtained by calcination at 250&#xa0;°C, exhibits the largest specific surface area, superior low-temperature reduction capability, and enhanced oxygen species activity, leading to its optimal catalytic performance in the photothermal oxidation of toluene. Under a light intensity of 400 mW/cm², toluene conversion reaches 95%, and the CO₂ yield attains 80% on C-Co₃O₄-250 during continuous flow reactions, much higher than that of 18% and 10% on pure Co₃O₄.</p> Graphical Abstract <p></p>