Rational design of Ag@Ag-Bi-KBa2Ta5O15 nanocomposites as efficient plasmonic photocatalysts for degradation of organic pollutants in water under visible light

Abstract

Bismuth (Bi) and silver (Ag) co-doped KBa2Ta5O15 nanocomposites were fabricated and modified with Ag nanoparticles (NPs) to form a novel visible light-driven plasmonic photocatalyst (Ag@Ag-Bi-KBT) for photodegradation applications. X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, UV–vis diffuse reflectance spectroscopy and high resolution transmission electron microscopy have been conducted to investigate the structural, morphological, electronic and optical characteristics of the photocatalysts. The photocatalytic activity of the Ag@Ag-Bi-KBT nanocomposites has been systematically evaluated by photodegradation of four organic contaminants (rhodamine B, orange G, methyl orange and bisphenol A) in aqueous solution under visible light irradiation (λ>420nm). The degradation mechanism over Ag@Ag-Bi-KBT is discussed. Ag@Ag-Bi-KBT exhibits high photocatalytic activity under visible light irradiation, mainly due to increased reaction sites and strong visible light absorption by Bi- and Ag-co-doping, as well as to the optimized localized surface plasmon resonance behavior and efficient charge separation resulting from Ag NPs.