Selective laser-induced photothermal effect in a semiconductor-based nanocomposite for boosting the photocatalytic performance in degradation of organic pollutant

Abstract

In recent years, the laser-fabrication technology has attracted significant attention in processing the nanomaterials. Comparing with the conventional wet chemical routes and thermal annealing processing method, even though the relevant products can be well-prepared by using these methods, but the spherical nanomaterials widely used in photocatalytic fields, with neat surface and precisely controllable temperature are hard to realize. Laser technology enables the fabrication of nanospheres, which act as atomic clusters to expand the performance of functional semiconductors. In this work, an innovative approach is proposed to increase photogenerated carrier of g-C₃N₄. Under laser irradiation, g-C₃N₄ was successfully welded to Ag nanospheres, which was observed and confirmed using high-precision instruments. Additionally, a numerical simulation under typical liquid-phase conditions at the nanoscale is elaborated, and efficient heat generation under electromagnetic radiation is calculated. The surface temperature of the Ag nanoparticles was 1415 K. A Schottky barrier between Ag and g-C₃N₄ was naturally established, and the performance of the photogenerated charge carriers was effectively enhanced. Degradation of organic pollutants was carried out as a typical example to demonstrate the photogenerated carrier performance. The maximum reaction rate was accelerated by 14 times, and an increased Electron Paramagnetic Resonance (EPR) intensity of 1.8 times was obtained. The optimized photocatalytic mechanism was investigated. This work demonstrates an efficient approach for the precise construction of nanomaterials and provides a valuable way to optimize the photogenerated carrier performance of semiconductors.