Morphology-controlled synthesis and growth mechanism of ZnO nanostructures via the NaCl nonaqueous ionic liquid route

An environmentally friendly NaCl nonaqueous ionic liquid route has been developed to synthesize ZnO nanostructures including nanowires and nanoplates for the first time. ZnO nanostructures were prepared by decomposing precursor Zn5(CO3)2(OH)6 nanoparticles in NaCl nonaqueous ionic liquid, in which the precursor Zn5(CO3)2(OH)6 nanoparticles were first prepared by a facile one-step, solid-state reaction and ground with both NaCl and NP-9 or only in NaCl, then heated at 850 °C for 2 h. XRD, TEM and HRTEM techniques were used to investigate chemical composition, morphology, size, and microstructure features of the as-prepared ZnO nanostructures. The comparative experiments have been conducted systematically to investigate the growth mechanism of ZnO nanostructures, and the roles of salt NaCl nonaqueous ionic liquid and surfactant nonyl pheyl ether (9) (NP-9) on the formation of ZnO nanostructures. The experimental results demonstrated that ZnO nanowires were achieved by decomposing precursor Zn5(CO3)2(OH)6 nanoparticles in NaCl nonaqueous ionic liquid, in which the precursor Zn5(CO3)2(OH)6 nanoparticles were firstly ground with NaCl and NP-9, while ZnO nanoplates were obtained by decomposing precursor Zn5(CO3)2(OH)6 nanoparticles in NaCl nonaqueous ionic liquid, in which the precursor Zn5(CO3)2(OH)6 nanoparticles were firstly ground with NaCl in absence of NP-9. A rational interpretation has been given for the growth of ZnO nanowires and nanoplates.