Sustainable Preparation of Copper Particles Decorated Carbon Microspheres and Studies on Their Bactericidal Activity and Catalytic Properties

Abstract

Cu particles decorated carbon composite microspheres (CCMs) with a unique sesame ball structure have been prepared by combining the mass-producible spray drying technique with calcinations. The conventional cuprammonium cellulose complex solution obtained by dissolving cellulose in a cuprammonia solution has been applied as raw materials for the preparation of Cu(NH3)42+/cellulose complex microspheres via a spray drying process. The resulted Cu(NH3)42+/cellulose complex microspheres are then transformed into the Cu particles homogeneously decorated porous carbon spheres in situ by calcinations at 450 or 550 °C. The coordination effect between the Cu(NH3)42+ species and the hydroxyl groups of the cellulose macromolecules has been exploited for directing the dispersion of the Cu particles in the resultant composite CCMs. The antimicrobial effects of the CCMs are evaluated by determining the minimum growth inhibitory concentrations using Staphylococcus aureus and Escherichia coli as representatives, respectively. The CCMs show high efficiency catalytic properties to the conversion of 4-nitrophenol to 4-aminophenol using NaBH4 as a reductant in a mild condition. The recyclability and stability of the CCM catalysts have also been studied.