Sunlight-driven photocatalytic degradation of industrial dyes using Withania Somnifera decorated MnO2 nanoparticles

Abstract

The level of pollution in water bodies has recently increased to a concerning degree due to the expansion of industrial activities. The consumption of organic dyes in textile industries has also set up an alarming situation worldwide for their side-effects. These pigments are typically persistent and challenging for traditional wastewater treatment methods to break them down. The present study reports a novel, rapid, and green method for the synthesis of MnO2 nanoparticles using the Withania Somnifera (Ashwagandha) extract. The techniques such as UV-Vis spectroscopy, FESEM, FTIR, EDX were employed to confirm the synthesis of the prepared nanoparticles. Bromocresol green and Bromothymol blue were set up as benchmark for measuring the photocatalytic efficacy of the prepared nanoparticles. It was observed that the prepared nanocatalyst on the sunlight exposure displayed excellent removal effectiveness for both the dyes i.e. 92% for Bromothymol blue and 95% for Bromocresol green respectively for a time period of 1 h. The effect of parameters such as time, dose of photocatalyst, and photodegradation kinetics was also systematically investigated for evaluating the effectiveness of the developed photocatalyst. The developed method is easy to implement, is environment friendly and does not require any chemical agents or sophisticated instrumentation for synthesis. This opens a novel avenue for the development of green photocatalyst which can emerge as an exceptional nanomaterial for the waste water remediation.