Room temperature optical response of zinc oxide nanowires synthesized by chemical bath deposition to toluene vapors

Abstract

International audienceZinc oxide (ZnO) nanowires were synthesized by a simple and cost-effective process, namely chemical bath deposition. X-ray diffraction (XRD) pattern clearly shows that the nanowires are well crystallized in the wurtzite hexagonal structure. Field-emission scanning electron microscope (FESEM) images show the formation of perfectly aligned and organized nanowires, with no defects visible on their surface. The diameter and length of nanowires is 65 and 850 nm, respectively. The room temperature UV-excited photoluminescence spectra show the excitonic band in the UV and a wide emission band centered in the visible. This excitonic and visible emission is studied in the presence of toluene vapors and the results demonstrate the change of the visible photoluminescence of ZnO nanowire array and that the material is able to adsorb toluene. Finally, the mechanism of toluene sensing is discussed. (C) 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinhei

Synthesis of Monodispersedly Sized ZnO Nanowires from Randomly Sized Seeds

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“…We serendipitously found the emergence of monodisperse ZnO nanowires from randomly sized seeds when hydrothermal synthesis − ,− was conducted by a two-step process composed of an ammonia-added “step 1” and an ammonia-free “step 2”. Figure a,b shows typical field emission scanning electron microscopy (FESEM) images of ZnO nanowires fabricated by two-step and single-step growth, respectively.…”

Smart Engineering of New Materials

“…The authors report herein various material synthesis aspects like zirconia coatings fabricated by aerosol‐gel routine, enhanced with low temperature plasma discharge , 65 nm‐thick ZnO nanowires grown by a cost‐effective process called chemical bath deposition or ALD growth of electrically efficient ZnO/4H‐SiC n‐p heterojunction diodes .…”