Enhanced efficiency of AgAlO2/g-C3N4 binary composite to degrade organic pollutants for environmental remediation under visible light irradiation

Abstract

This study explores the utilization of semiconductor-based photocatalysts for environmental remediation through photocatalytic degradation, harnessing solar energy for effective treatment. The primary focus is on the application of photocatalytic technology for the degradation of 2-chlorophenol and methylene blue, critical pollutants requiring remediation. The research involves the synthesis of binary AgAlO₂/g-C₃N₄ nanocomposites through an exchange ion method, subsequent calcination, and sonication. This process enhances the transfer of photogenerated electrons from AgAlO₂ to g-C₃N₄, resulting in a significantly increased reductive electron charge on the surface of g-C₃N₄. The photocatalytic activity of the synthesized composites is comprehensively examined in the degradation of 2-chlorophenol and methylene blue through detailed crystallographic, electron-microscopy, photoemission spectroscopy, electrochemical, and spectroscopic characterizations. Among the various composites, AgAlO₂/20% g-C₃N₄ emerges as the most active photocatalyst, achieving an impressive 98% degradation of methylene blue and 97% degradation of 2-chlorophenol under visible light. Notably, AgAlO₂/20% g-C₃N₄ surpasses bare AgAlO₂ and bare g-C₃N₄, exhibiting 1.66 times greater methylene blue degradation and constant rate (k) values of 20.17 × 10^-3 min^-1, 4.18 × 10^-3 min^-1 and 3.48 × 10^-3 min^-1, respectively. The heightened photocatalytic activity is attributed to the diminished recombination rate of electron-hole pairs. Scavenging evaluations confirm that O₂^•- and h⁺ are the primary photoactive species steering methylene blue photodegradation over AgAlO₂/g-C₃N₄ in the visible region. These findings present new possibilities for the development of efficient binary photocatalysts for environmental remediation.

Keywords: 2-Chlorophenol; AgAlO(2)/g-C(3)N(4); Binary photocatalyst; Environmental remediation; Methylene blue; Photocatalytic degradation.