Mussel-inspired Ag/poly(norepinephrine)/MnO₂ heterogeneous nanocatalyst for efficient reduction of 4-nitrophenol and 4-nitroaniline: an alternative approach

Abstract: Noble metal-based surface chemistry is a well-practiced domain on interest in catalysis. A newborn in mussel-inspired coating based on catecholic chemistry, poly(norepinephrine) (PNE), has been synthesized via cyclization polymerization technique over MnO₂ nanosheets. The physisorped PNE macromolecular chains over MnO₂ nanosheets act as green reducing agent for silver ions resulting in arresting the quasi-spherical silver nanoparticles distributed over the MnO₂-PNE assembly. The catalytic activity was performed against nitroaryl molecules which evidenced fast reduction with pseudo-first-order kinetics. The superiority which lies in this work is their facile preparation, high surface area due to sheet-like morphology, and fast catalytic reduction. These practical observations spread its window as nanocatalyst toward environmental remediation of hazardous nitroaryl compounds. Graphic abstract: [Figure not available: see fulltext.].