Development of spinel oxide/attapulgite composite for photothermal catalytic degradation of toluene

The degradation of large flow volatile organic compounds (VOCs) at low temperature remains a significant challenge. Photothermal catalytic technology, which integrates the advantages of photocatalysis and thermal catalysis, has the potential to address this challenge. In this work, using attapulgite (ATP) as the substrate, MnCo 2 O 4.5 /ATP composites with various spinel loading amount were prepared via a sol-gel approach. Results demonstrated that the 20 % MnCo 2 O 4.5 /ATP catalyst presented the best catalytic performance at a space velocity of 10,000 mL·g −1 h −1 (500 ppm toluene) under light illumination. The toluene conversion rate and mineralization rate reached 99 % and 81 %, respectively. The surface temperature of MnCo 2 O 4.5 /ATP composite rapidly increased under Xenon lamp irradiation, reaching as high as 301.6 °C. In-situ DRIFTS and DFT calculations were performed to explore the photothermal catalytic reaction mechanism. The effective MnCo 2 O 4.5 /ATP interface facilitated the mobility of lattice oxygen and strengthened the activation of oxygen. The ATP surface with its high surface area and rich hydroxyl groups promoted the adsorption of toluene. The oxygen vacancies enriched on the surface of MnCo 2 O 4.5 intensified the adsorption and activation of oxygen, facilitating the transformation of toluene at the MnCo 2 O 4.5 /ATP interface. Current work offers a new strategy for the efficient catalytic elimination of VOCs by taking advantage of solar energy and minerals.