LAUSR

Abstract In this work, we design a facile green preparation of CuO-bentonite-gold nanocomposites by a pillarization-immobilization method. Bentonite has been successfully pillared with CuO (CuO-Bentonite) by using Tinospora crispa leaf extract. Gold nanoparticle (AuNPs) has immobilized in the interlayer of CuO-Bentonite. The presence of an amine group acts as a source of nitrogen bases for a hydrolyzing agent in the formation of CuO-bentonite. Meanwhile, the flavonoid secondary metabolites play an essential role in reducing Au3+ to Au0 nanoparticles. The dspacing value of CuO-bentonite was greater than dspacing value of Na-bentonite at 2θ of 5.290, indicating CuO has been pillared in the bentonite interlayer. Moreover, AuNPs was systemically formed on CuO-bentonite confirmed by XRD and EDX. The morphology of CuO-bentonite-gold nanocomposites was in a layered shape with a particle size of approximately 30 nm. Additionally, this work reported a simple, affordable, and less-toxic method to modify bentonite to enhance their layers for better performance.