Surface Roughness Effects of Pd‐loaded Magnetic Microspheres on Reduction Kinetics of Nitroaromatics

Abstract

Metal nanoparticles decoration on magnetically active semiconductor materials is a common strategy to improve the colloidal stability, catalyst harvesting, and reuse. In this study, a surfactant‐free solvothermal method followed by a heat treatment to prepare highly surface roughened α‐Fe2O3 (Hematite)/Pd microspheres (MSPs) is reported. Amine‐functionalized silicate sol‐gel matrix is used as a stabilizing agent for the solvothermal synthesis of Prussian blue (PB) MSPs using HCl at 80 °C for 20 h. It is observed that modulating HCl concentration in a medium led to a high degree of improvement in surface roughness. Employing heat treatment at 350 °C for 6 h, PB MSPs are transformed into α‐Fe2O3, Hematite phase. Fabricated Hematite/Pd MSPs have shown high catalytic reduction activity over p‐nitrophenol. Reduction kinetics of nitroaromatics is monitored using UV‐vis absorption spectroscopy and product formation is confirmed by 1H and 13C NMR analyses.