Tin Oxide Supported on Nanostructured MnO2 as Efficient Catalyst for Nitrophenol Reduction: Kinetic Analysis and Their Application as Heterogeneous Catalyst

Abstract

Recently, metal oxides-based have been widely used for catalytic reduction of nitro-aromatic compounds, which are notorious for their carcinogenic nature. The current study reports Sn-doped MnO2 as an efficient catalyst for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). The FE-SEM characterization of SnO2-doped MnO2 revealed the diffused flower-like morphology. Further, the XPS survey scans were performed to investigate the binding energies, oxidation states, and elemental compositions of both MnO2 and Sn-doped MnO2. Kinetics analysis revealed that the catalytic reduction (> 98.8%) of 4-NP into 4-AP by Sn-doped MnO2 in the presence of NaBH4 occurs within four min, following pseudo-first order kinetics. Importantly, no observable deactivation of catalytic efficiency was noticed even after five cycles. Our strategy of loading SnO2 on the surface of semiconductor offers a versatile approach to enhance the catalytic performance, stability, and which may further promote their practical industrial application.