Crystalline Carbon Nitride Embedded with Pt Nanoparticles for Boosting Photothermal Degradation of Toluene

Degradation of volatile organic compounds (VOCs) by environmentally friendly methods remains a challenging issue. Photothermal catalysis, as an emerging green catalytic technology, merges the benefits of both thermal catalysis and photocatalysis, presenting itself as a viable strategy for VOC degradation. However, achieving higher catalytic performance by reasonably designing the synthetic route of catalyst carriers remains difficult. In this study, crystalline carbon nitride material, poly(triazine imide) (PTI), was prepared using a unique molten salt synthesis method and employed as a support for Pt to construct an exceptional photothermal catalyst. In a continuous-flow system under Xe lamp irradiation with external temperature control, toluene was efficiently degraded at a high rate of nearly 100% under low Pt content (0.31 wt%) and a relatively low operational temperature condition (143 °C). As a carrier of noble metals, PTI material exhibited a larger specific surface area and fewer structural defects, resulting in more efficient toluene conversion and mineralization. The joint action of photocatalysis and thermocatalysis synergistically facilitated the efficient generation of active species and accelerated charge transfer, thereby significantly boosting toluene catalytic oxidation. These findings provide valuable guidance for designing and optimizing photothermal catalysts for the removal of VOCs.