Probing Activity Enhancement of Photothermal Catalyst under Near-Infrared Irradiation.

Exploring highly efficient catalysts with excellent photothermal conversion and further unveiling their catalytic mechanism are of significant importance for photothermal catalysis technologies, but there remain grand challenges to these activities. Herein, we fabricate a nest-like photothermal nanocatalyst with Pd decorated on a N-doped carbon functionalized Bi2S3 nanosphere (Bi2S3@NC@Pd). Given its well-dispersed ultrafine Pd nanoparticles and the excellent photothermal heating ability of support material, the Bi2S3@NC@Pd composite exhibits a superior activity and photothermal conversion property to commercial Pd/C catalyst for hydrogenation of organic dyes upon exposure to near-infrared (NIR) light irradiation. In addition, the photothermal effect (temperature rise) and activity enhancement of the heterogeneous catalysis system are further probed by comparing the reaction rate with and without the NIR light irradiation. Furthermore, the catalytic behaviors of the Bi2S3@NC@Pd catalyst under conventional and photothermal heating are investigated at the same reaction temperature. This work not only improves our fundamental understanding of the catalytic behavior in heterogeneous liquid-solid reaction systems under near-infrared irradiation but also may promote the design of catalysts with photothermally promoted activity.