ZnO/Ag2ZrO3 nanocomposites: A tailored nanostructure for enhanced supercapacitor, photocatalytic & antimicrobial applications

The present study reported the synthesis of a novel ZnO/Ag2ZrO3 nanocomposite by a two-step method, involving hydrothermal synthesis followed by a co-precipitation method. As synthesized ZnO/Ag2ZrO3 nanocomposite was further used for the supercapacitor study, photocatalytic dye degradation, and antimicrobial applications. It was fairly challenging to enhance the supercapacitor performances of ZnO. Therefore, it was imperative to develop a novel approach utilizing a binary nanostructure composed of ZnO and Ag2ZrO3. This strategy aims to synergistically enhance the energy storage and conversion capabilities of inorganic materials, while simultaneously augmenting the photocatalytic and antimicrobial activity in the synthesized ZnO/Ag2ZrO3 nanocomposites. Among ZnO, Ag2ZrO3, and ZnO/Ag2ZrO3 nanocomposites with a varying weight percentage of Ag2ZrO3 (10 %, 20 %, 30 %, & 40 %), the ZnO/Ag2ZrO3 (20 %) electrode exhibited the highest specific capacitance (463.3 Fg(-1)) and energy density (10.2 Whkg(-1)) at current density 1 mAcm(-2). Furthermore, we examined the photocatalytic activity, in the presence of persulfate ion (PS), the ZnO/Ag2ZrO3 (20 %) nanocomposite demonstrated superior degradation efficiency for Rhodamine B (RhB), Methyl Orange (MO), and Methylene Blue (MB). Almost 100 % degradation of RhB was observed in just 120 min of visible light irradiation, whereas only 27.6 %, 62.4 %, and 42.7 % of RhB degradation was observed on the pristine ZnO, ZnO/PS, and ZnO/Ag2ZrO3 (20 %) materials, respectively. This enhanced photocatalytic activity was attributed to the synergetic effect of photoinduced electron activating PS ions to form sulfate radicals ((SO4-)-S-center dot), higher visible light harvesting by ZnO/Ag2ZrO3 nanocomposite, and better charge separation. Five cycles of reusability test with no significant loss in dye degradation efficiency, confirms the stability test of ZnO/Ag2ZrO3 (20 %) nanocomposite. Moreover, the synthesized ZnO/Ag2ZrO3 (20 %) nanocomposite possesses improved antimicrobial potential against both gram +ve and gram -ve bacteria.