Ionic liquid-assisted synthesis of Ag/Ag2Te nanocrystals via a hydrothermal route for enhanced photocatalytic performance

Abstract

Herein, Ag₂Te and Ag/Ag₂Te nanocrystals were synthesised via a hydrothermal method using diphenyl ditelluride as a new tellurium source and 1-butyl-3-methyl imidazolium acetate (BMIA IL) as a structure controlling and conducting coating source. The as-synthesized nanocrystals were characterized via XRD, SEM-EDS, XPS, TEM, FTIR, UV-vis, and PL measurements. The photocatalytic behaviour of the Ag₂Te and Ag/Ag₂Te nanocrystals was investigated for the degradation of methylene blue in the presence of UV-visible light. After 90 minutes of photo-irradiation, up to 95.74% of the dye was photocatalytically degraded by the Ag/Ag₂Te nanocrystals. This improved photocatalytic activity was achieved due to the effective charge separation, synergic effect of the Ag₂Te semiconductor and plasmonic metallic Ag, conducting BMIA IL coating, and morphological features of the nanocrystals. The appearance of strong peaks in the photoluminescence emission spectra at room temperature suggests a high-level transition in the prepared plasmonic photocatalyst system. The enhanced photocatalytic mechanism for dye degradation using the Ag/Ag₂Te nanocrystals has also been described. Thus, the present report presents new insight into the design and development of Ag/Ag₂Te plasmonic photocatalysts for environmental applications.