HEPES-mediated controllable synthesis of hierarchical CuO nanostructures and their analogous photo-Fenton and antibacterial performance

Abstract

Owing to the strongly morphology and size-dependent properties of nanomaterials, developing a simple and eco-friendly approach for controlling synthesis and assembly of hierarchical CuO nanostructures plays a critical role. In this work, we successfully developed an eco-friendly and facile hydrothermal route for controllable synthesis of various morphologies CuO nanostructures, where traditional and toxic additives were replaced by biocompatible 4-(2-hydroxyethyl)-1-piperazineethane-sulfonic acid (HEPES). The growth rate and orientation of CuO nanoparticles were tuned through adjusting the concentration and pH value of HEPES. The XRD pattern, SEM, UV-DRS, and BET indicated CuO nanostructures maintained high purity and excellent crystalline nature and showed more regular morphology and size with enhanced visible light absorption. The analogous photo-Fenton assay demonstrated that the as-prepared CuO nanostructures present enhanced dye removal capability when compared with CuO synthesized in pure water. Furthermore, the antibacterial assay on S. aureus was also investigated, and CuO nanoparticles with smallest size displayed the best antibacterial performance. These results reveal that HEPES shows a remarkable influence on the possible application of as-prepared CuO nanostructures which having great potential in pollutant removal.