Silver-doped SnO2 nanostructures for photocatalytic water splitting and catalytic nitrophenol reduction

Abstract

Driven by the quest for renewable and clean energy sources, researchers all around the globe are seeking solutions to replace non-renewable fossil fuels to meet the ever-increasing energy supply requirements and solve the relevant environmental concerns. In this study, as a promising photocatalyst, silver-doped SnO₂ (Ag–SnO₂) nanoparticles (NPs) (1%, 2.5%, and 5%) were synthesized without any additives by employing a simple and environmentally friendly modified hydrothermal route. The optical bandgap was found to be 3.15, 3.08, and 3.00 eV for the 1%, 2.5%, and 5% Ag–SnO₂, respectively. The surface area was found to be 85, 54, and 53 m² g⁻¹ for the 1%, 2.5%, and 5% Ag–SnO₂, respectively. The studies showed the H₂-production rate of the 1% Ag–SnO₂ NPs from photocatalytic water splitting was 19.04 mmol g⁻¹, which was much higher than that of the 2.5% and 5% Ag–SnO₂ NPs. Furthermore, all of the as-synthesized Ag–SnO₂ NPs could significantly reduce 4-nitrophenol (4-NP) to 4-aminophenol (4-AP), especially the 5% Ag–SnO₂ NPs, which exhibited exceptional performance in its catalytic activity, reducing 4-NP to 4-AP in just 5.5 min. Our report elucidates the efficient photocatalytic and catalytic performance of Ag–SnO₂ NPs for hydrogen-evolution and organic-degradation conversion reactions.