Pseudo-SILAR assisted unique synthesis of ZnO/Ag2O nanocomposites for improved photocatalytic and antibacterial performance without cytotoxic effect

Abstract

The combination of silver (I) oxide (Ag2O) with zinc oxide (ZnO) evolves the magnificent response of composite for antimicrobial and photocatalytic applications concomitantly. A novel, cost-effective and facile wet-chemical recipe for developing ZnO/Ag2O nanocomposites is realized by customizing pseudo-successive ionic layer adsorption and reaction (p-SILAR) process. Quantitatively as well as qualitatively controlled Ag2O was deposited on flower-like ZnO, termed as ZnO NFs, by carrying out 1-4 cycles of customized p-SILAR. It was affirmed that the cationic adsorption of Ag+ from AgNO3 solution instigates the formation of Ag2O over ZnO NFs via a simple heat-treatment process. Followed by the customary material characterizations including SEM, TEM, XPS etc., the ZnO/Ag2O nanocomposites were tested for controlling the toxic organic dye (Rhodamine B) and harmful bacterial species i.e. E. coli and B. subtilis. A significant increase in the photocatalytic performance of ZnO NFs under ultra-violet (UV) as well as visible (vis) irradiation was obtained by incorporating 2 cycles of Ag2O deposition. Consequently, the degradation rate constant of optimal ZnO/Ag2O-2C was increased to 0.1077 and 0.0104 from 0.0235 and 0.0011 min(-1), under UV and vis light respectively. Similarly, ZnO/Ag2O evolved a significant increase in the inhibition zones without exhibiting a considerable decrease in the cell viability of HepG2, which further avowed the bio-compatibility of ZnO NFs having Ag2O.