Facile synthesis of zinc hydroxyfluoride nanobelt and effect of hexamethylenetetramine for growth direction

Control of nanomaterial morphology has been investigated to utilize for the desired application. 1D nanomaterials are ideal for various applications because of their excellent carrier transportability and huge specific surface area. Due to their advantages, various methods have been developed to grow in a specific direction. Herein, we introduced a simple synthesis method of freestanding Zinc hydroxidefluoride (ZnOHF) nanobelt as 1D material without seed or substrate using aqueous solutions. The ZnOHF nanobelt was synthesized using zinc fluoride and hexamethylenetetramine (HMT) at 80°C for 3 h. Even though low synthesis temperature, ZnOHF demonstrated good crystallinity and a homogeneous nanobelt structure. The ZnOHF nanobelts were grown over several μm to <010> direction with less than 100 nm width. In addition, the growth direction of the nanobelt was controlled by the concentration of HMT. The width of the nanobelt was broader by a decrease in HMT concentration. It was considered that crystal nucleation and growth of ZnOHF could be influenced by OH− and NH4+ ions generated from HMT decomposition.