Mesoporous ZnO nanoparticles using gelatin - Pluronic F127 as a double colloidal system for methylene blue photodegradation

Abstract

ZnO nanoparticles with mesopores enhanced the photocatalytic degradation of dyes. The potential of gelatin-Pluronic F127 as a double colloidal system was investigated for constructing mesoporosity in ZnO nanoparticles. Amphoteric gelatin with hydrophobic and hydrophilic tails formed a stable colloid as the surface-active agent. The studies highlighted the effect of different zinc precursors (zinc acetate, zinc sulphate and zinc nitrate) on ZnO formation and methylene blue (MB) degradation activity. Porous ZnO nanoparticles with uniform hexagonal structures were formed when zinc acetate exhibited a higher photocatalytic activity. Unprecedented ZnSO4 resembling gunningite mineral was produced following high temperature calcination when using zinc sulfate as a precursor. The effect of temperature and concentration of MB solution indicated photodegradation reaction undergoes the first-order kinetic model. The mechanism of photocatalytic degradation of MB was determined using different types of scavenger agents, which indicated that hydroxyl radicals catalyzed the reaction.