Influence of concentration on the geometry of ZnO nanostructures prepared by chemical bath deposition

Abstract

Zinc Oxide (ZnO) nanostructures such as nanorods (NRs), nanowalls (NWs) and nanoflakes (NFs) were successfully grown on a glass substrate via chemical bath deposition (CBD) method by varying solutions concentration (0.01 M, 0.05 M, 0.10 M, 0.15 M, 0.20 M and 0.25 M). Effect of CBD concentration on the growth and morphology of ZnO nanostructures are dignified. The structural and optical properties of ZnO NRs, NWs, and NFs were investigated by Field Emission Scanning Electron Microscope (FESEM), energy-dispersive X-ray (EDX), X-Ray Diffraction (XRD), and UV-Visible (UV-Vis) analyses. Results reveal that as the CBD concentration increases, FESEM images showed differ top-down morphology of ZnO nanostructures from NRs, NWs to NFs. Likewise, the alignment of ZnO cross-section evolved from randomly oriented to vertically oriented. As revealed by EDX, the stoichiometric ratio of Zn:O were mostly towards 1:1. From XRD analyses, the preferred structure was wurtzite hexagonal with c-axis orientation along (002) plane. The UV-Vis analysis exposed the optical band gap energy closes to the standard energy gap value of ZnO at 3.37 eV. Thus, this work introduces a variable geometry of ZnO nanostructures (NRs, NWs, and NFs) grown on glass with high structural and optical quality as standard ZnO. The fabricated materials are potential candidates for investigating random lasing in ZnO from different structural geometry.

Influence of Zinc Salt Concentration on Structured ZnO Composition and Morphology

“…The preferential orientation (002) confirmed the vertical growth of the ZnO hexagonal nanorods along the c‐axis perpendicular to the substrate. Similar (002) preferential orientation in ZnO nanorods have been reported by other authors [15–18] . However, samples prepared at larger concentration, 0.05, 0.1 and 0.15 M of ZnCl2‐HMT aqueous solution exhibit significantly different diffraction patterns than the sample prepared at low molarity 0.01 M, their pattern are composed of various peaks located at 2θ=11.5°, 23°, 34.5° and 46.5°, which are attributed to the (003), (1 0 4), (202) and (0012) diffraction planes respectively (ICSD No.…”

“…Similar (002) preferential orientation in ZnO nanorods have been reported by other authors. [15][16][17][18] However, samples prepared at larger concentra-tion, 0.05, 0.1 and 0.15 M of ZnCl2-HMT aqueous solution exhibit significantly different diffraction patterns than the sample prepared at low molarity 0.01 M, their pattern are composed of various peaks located at 2θ = 11.5°, 23°, 34.5°and 46.5°, which are attributed to the (003), (1 0 4), ( 202) and (0012) diffraction planes respectively (ICSD No. 77-2311) of the hexagonal simonkolleite (SK) phase owing the formula Zn 5 (OH) 8 Cl 2 2H 2 O..…”

Incorporation of Zinc Oxide on Macroporous Silicon Enhanced the Sensitivity of Macroporous Silicon MSM Photodetector

“…20,21 Furthermore, the presence of ZnO helps in promoting the desirable high energy photon to excite electrons from the valence band (VB) to the conduction band (CB) and encourage UV light reaching the space charge region and finally increase the photocurrent. 22,23 Most of previous works presented the synthesized of ZnO and other semiconductor structures that sheltered or shielded on the PS layer for PDs application. [24][25][26][27] This work however revealed the cooperation of ZnO/mPS whereby the ZnO nanostructures was unevenly distributed in such way that exposing the mPS surface.…”