Photocatalytic action of Ag/TiO2 nanoparticles to emerging pollutants degradation: A comprehensive review

Abstract

Silver (Ag) doped titanium dioxide (TiO₂) nanoparticles are promising photocatalysts for the degradation of emerging pollutants. These nanocomposites enhance the photocatalytic activity of TiO₂ in visible light, suppress the e^-/h⁺ rearrangement, and enhance their bactericidal properties. This review proposes a bibliometric analysis that elucidates research trends, and important topics on contaminant degradation, analyzes the advantages and limitations of different synthesis techniques (solvothermal, photochemical reduction, sol-gel, and others), their properties to produce Ag/TiO₂, and their potential for pollutant degradation. Thus, depending on the technique chosen, Ag doping of TiO₂ can offer high stability, recyclability for more than 3 cycles, customized morphologies and sizes, among others. Applications of Ag/TiO₂ include wastewater treatment, antibacterial surfaces, food packaging, implants, and others. Advances in the synthesis of Ag/TiO₂ photocatalysts offer excellent photocatalytic degradation, between 80 % and 100 %, for organic dyes, hormones, pharmaceuticals, pesticides and other emerging pollutants. Ag/TiO₂ photocatalysts show superior degradation rates compared to pure TiO₂, with some achieving up to 99 % pollutant removal. The bibliometric analysis performed by Methodi Ordinatio, classifying 267 articles, reveals a foundation of relevant articles, around 35 % of articles published on these topics were published between 2019 and 2021. A complete cost analysis of Ag/TiO₂ is considered to determine the feasibility for pilot and large-scale experimentation. These nanocomposites offer a promising solution to address the growing concern about emerging pollutants, disinfection of water, and in the inactivation of pathogenic microorganisms.