Optimal Zn/O ratio in vapor phase for the synthesis of high quality ZnO tetrapod nanocrystals via thermal evaporation of Zn in Air

► Tetrapod ZnO nanocrystals were synthesized through thermal evaporation of Zn in air. ► There is an optimal Zn/O ratio required for the synthesis of tetrapod ZnO nanocrystals. ► Zn/O ratio in vapor phase had an effect on the optical properties of tetrapod ZnO nanocrystals.