Polymorphous ZnO complex architectures: Selective synthesis, mechanism, surface area and Zn-polar plane-codetermining antibacterial activity

Complex ZnO architectures with tunable morphologies and structures were obtained by modulating only the base type and molar ratio of base to Zn ²⁺ (α) using an easy one-pot hydrothermal approach without any template or organic additive. Characterizations by X-ray diffraction, Fourier-transform infrared spectrometry, scanning electron microscopy, transmission electron microscopy, and surface area analysis were performed. The effect of the base type and base/Zn²⁺ molar ratio on the morphology and corresponding mechanism were determined. The correlations between the microstructure and properties were established. The antibacterial effect of the ZnO samples was probably due to a combination of variable factors. Better antibacterial activity is derived from more effective antibacterial surfaces, which are mainly associated with the specific surface area and Zn-polar plane. Thus, flower-like architectures with larger specific surface areas and more highly exposed (0001) Zn-polar surfaces outwards are promising structures for ZnO antibacterial agents. This work provides a guide for devising and synthesizing highly efficient antibacterial materials.