Nature-inspired α-MnMoO4 nanocubes from Arachis hypogaea for next-generation wastewater treatment and organic pollutant catalysis

Abstract

In this study, bimetallic α-MnMoO₄ nanoparticles (NPs) were successfully synthesized via a one-step solution combustion method using Arachis hypogaea (peanut) seed powder as a green fuel. This eco-friendly route was adopted to explore the adsorption, photocatalytic, and catalytic properties of the resulting NPs. The structural, morphological, and optical characteristics of α-MnMoO₄ NPs were systematically characterized using XRD, FTIR, UV-vis, and PL spectroscopy, SEM, and EDX techniques. Notably, α-MnMoO₄ NPs demonstrated excellent adsorption capability toward methylene blue (MB) dye, achieving a removal efficiency of 86.70%, which was primarily attributed to their negatively charged surface. Moreover, the nanoparticles demonstrated a remarkable photocatalytic activity, achieving 81.55% degradation of MB through the photo-oxidation of water into hydroxyl (ȮH) radicals by photogenerated holes. Beyond dye remediation, the study further explored the catalytic capabilities of o-phenylenediamine via oxidative condensation with substituted aromatic aldehydes to synthesize benzimidazole derivatives, achieving yields ranging from 35% to 85%, depending on the substituents used. This integrated approach highlights the potential of α-MnMoO₄ NPs not only in pollutant removal but also in facilitating the green synthesis of high-value chemical products, demonstrating promising applications in environmental remediation and fine chemical industries.