Synthesis and Characterization of ZnO Nano and Micro Structures Grown by Low Temperature Spray Pyrolysis and Vapor Transport

Abstract

In this work we present a systematic study of ZnO micro and nanostructures grown by spray pyrolysis (SP) and by physical vapour transport (PVT) on glass and c-sapphire substrates at low temperatures. Optimised growth conditions have allowed to obtain homogeneous ZnO nanolayers composed of quasi-spherical nanoparticles in the range 2 to 8 nm by spray pyrolysis, while by PVT the selected growth conditions allow to produce a wide variety of morphologies (tripods, grains, arrows and wires) of nano and microsize dimension. Grazing incidence X-ray diffraction, field emission scanning electron microscopy (FE-SEM), high resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED) and energy dispersive X-ray spectroscopy (EDX) were used as characterization techniques in the investigation of structural, morphological and compositional nature of these nanostructures in relation with the growth method.

Recent Advances in ZnO Nanomaterial-Mediated Biological Applications and Action Mechanisms

“…To date, a wide variety of ZnO nanoparticle preparation methods have been put forward, from physicochemical synthesis to green biogenic synthesis. Initially, physicochemical synthesis was the common preparation means, which mainly includes the methods of precipitation [16][17][18][19][20][21], electrochemical deposition [22][23][24], hydrothermal synthesis [25][26][27][28][29][30][31][32], sol-gel process [33,34], solid state reaction [35,36], chemical vapor synthesis [37], gel combustion [38], microemulsion [39], solvothermal synthesis [40][41][42], spray pyrolysis [43], sputtering [44][45][46], sonication [47,48], microwave [49], thermal evaporation [50][51][52] and so on. Each of these methods has its own advantages.…”

“…Additionally, it does not require complicated equipment and expensive raw materials, and thus is low cost and suitable for large-scale production [16,47]. Spray pyrolysis is suitable for large area preparation in a short span of time and its instrumentation is simple [43]. The solvothermal method is low-cost, simple, catalyst-free and seed-free [42].…”