Renewable RGO@CuI nanocomposites for redox triggered single electron transfer (SET) reaction under aerobic and anaerobic conditions

Renewable mineral derived nanocatalysts are of special interest to accomplish green and sustainable goals with unique advantages over homogeneous catalysts such as recyclability, robustness, superior activity and minimum waste generation. Here, we synthesized reduced graphene oxide supported copper iodide (RGO@CuI) nanocomposites from renewable malachite mineral derived RGO@CuO precursor by treatment with NH2OH and KI in water. The characterization results reveal the role of RGO sheets as capping agent and supporting material for CuO seeds which control the diffusion of iodide, NH2OH reagents and stabilizes the generated CuI prism morphologies. The RGO@CuI-20 nanocatalyst is robust to produce wide range of N-heterocycles such as 5-diarylamino benzimidazole and spiropyrroline via aerobic and anaerobic single electron transfer (SET) reactions, respectively. The nanocatalysis study delineates two distinct mechanistic pathways for aerobic and anaerobic SET reactions. The present method offers the advantages of utilizing a renewable copper precursor for catalyst preparation, catalyst recyclability over five times, excellent product yields and green reaction conditions with minimum waste (Low E-factor).