Spray pyrolysis deposition and characterization of highly c‐axis oriented hexagonal ZnS nanorod crystals

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Here we demonstrate that highly c‐axis oriented vertically aligned hexagonal ZnS nanorod‐like crystals have been synthesized via a facile and low‐cost spray pyrolysis method. ZnS layers were grown onto soda‐lime glass (SGL), glasses covered with transparent conductive oxides (TCOs: ITO and FTO) and silicon wafer substrates using zinc chloride and thiocarbamide precursors solution and air as carrier gas. The effect of main technological parameters on formation and properties of ZnS nanorods are studied. SEM, XRD, PL and UV‐VIS were applied to characterize the ZnS layers. Dimensions of the ZnS rods are mainly controlled by the deposition temperature, precursor concentration and substrate type. For instance, rods with d = 80–100 nm and l = 450 nm were obtained using ZnCl2 with c = 0.1 mol/L; whereas rods with d = ca. 80 nm and l = 250 nm were produced from ZnCl2 with c = 0.05 mol/L on glass. According to PL study, such defects as sulphur vacancies (Vs) are present in the ZnS samples, and concentration of Vs decreases with increasing the sulphur amount in solution.According to UV‐VIS, all ZnS layers possess high optical transmittance ca. 80% in the visible spectrum region; the Eg of ZnS is 3.7 eV independent of the deposition conditions, corresponding to wurtzite ZnS. ZnS rods produced at 550 and 580 °C show high haze factor values of ca. 90% at 320–350 nm revealing high light scattering ability. Vertically aligned, uniform in size ZnS rods can be directly grown onto glass, TCO and silicon substrates.