Influence of alkaline solutions on morphology of ZnO prepared by hydrothermal method for using as photocatalyst and bactericidal agent

•Multifunctional ZnO powders were synthesized by a hydrothermal method.•n-Propylamine can inhibit the crystal growth.•Alkaline solution influenced the particle shape.•The Eg value was influenced by crystallite size and defect concentration.•Photocatalytic and antibacterial activities depended on the particle shape.

ZnO powders were synthesized by a hydrothermal method. The crystallite size of ZnO decreased when n-propylamine was added into the solution. Hexagonal and rod-like ZnO structures formed when LiOH and NaOH were used as a precipitating agent, respectively. The Eg value depended upon the crystallite size and defect concentrations. The hexagonal ZnO platelets showed better photocatalytic efficiency compared to the rod-like ZnO powders. The rod-like ZnO shape exhibited better inhibitory activity against Staphylococcus aureus (S. aureus).