Cow urine-based green synthesis of sunlight-responsive ZrO2-Bi2O3 and its application in photocatalysis of 2,4-Dichlorophenoxyactetic acid in aqueous solution – Kinetics, mechanisms and sustainability analysis

The 2,4-dichlorophenoxyacetic acid (2,4-D) is an agrochemical used to remove weeds in paddy fields. Due to the toxicity associated, 2,4-D containing water needs treatment. Thus, herein, a sunlight-responsive ZrO2-Bi2O3 photocatalyst was prepared by green synthesis using cow urine and tested for its efficiency in degrading 2,4-D. The prepared ZrO2-Bi2O3 was then characterized in detail. The experimental results showed that 40% ZrO2-Bi2O3 showed the best photocatalytic activity and stable even after five cycles of reuse. Furthermore, the sustainability of the studied technique that was analysed by the newly developed “weightage-based ranking method” showed that the present work addressed 14 of 17 SDGs. [Display omitted] •Foremost study on cow urine based green synthesis of ZrO2-Bi2O3 nano photocatalyst.•ZrO2-Bi2O3-enabled degradation of 2,4-D and kinetics under sunlight were studied.•ZrO2–40%Bi2O3 at pH 6 functioned the best due to effective e−-h+ pairs suppression.•The photocatalytic performance of ZrO2-Bi2O3 was supported by characterization.•Study analysed sustainability of 4-functional elements using weightage based ranks.