In this study, vertically aligned zinc oxide (ZnO) nanorod (NR) arrays were grown with the 2step method. Spin coating was used to apply the seed layer, and by increasing the number of repetitions (n), higher thickness of the seed layer was achieved. The effects of different seed layer thicknesses, spin coated at different rotational speeds (v) and how the variables (v and n) influence the morphological and crystal properties of the resulting ZnO NRs were analyzed. The effects of 1, 3, and 5 (n), with (v) of 3000 or 4000 rpm were investigated, and the formed seed layers were characterized by using scanning electron microscopy (SEM) and X-ray diffraction (XRD) profiles. The ZnO NR arrays were grown by a chemical bath deposition method because of its simplicity and ease of use. Full width at half maximum (FWHM) analysis was conducted on the XRD chart and Raman spectrum to analyze the grain size and Wurtzite distortion of the ZnO NRs. A lower FWHM value was attributed to the lower number of structural disorders in the ZnO NRs, which equated to the most stable or structured Wurtzite structures in the ZnO NRs, achieved at the lowest FWHM value. The lowest FWHM for (002) XRD peak was obtained at 0.35° for ZnO NRs grown with a seed layer spin coated at 4000 rpm once. The crystallite size calculated by Scherrer's equation gave a size of 25.14 nm. The lowest FWHM for E2(High) Raman peak was obtained at 6.00 cm-1 for ZnO NRs grown with a seed layer spin coated at 4000 rpm three times.
Arrays of zinc oxide (ZnO) nanorod (NR) were fabricated in a vertical axis direction through the two-step method of seed layer’s deposition and growth of the NR. The seed layer was applied by spin coating with a three-time repetition (n) and rotational speed (v) at 3000 rpm. After the seed layer had grown, ZnO NRs were grown with a growth solution made by combining one zinc source with one hydroxide source. There were two different zinc sources, i.e., zinc acetate dehydrate and zinc nitrate hexahydrate and, for comparison, zinc acetate (ZA) and zinc nitrate (ZN) were each combined with the same hydroxide source, hexamethylenetetramine (HMT). Later, the growth solutions were processed by the chemical bath deposition (CBD) method using a waterbath machine. The CBD method was started at room temperature until it reached the designated temperature at 85°C. At that point, the growth time was calculated from the zero-minute condition. It was found that ZnO NRs had already grown at a thickness of about 100 nm for both ZA and ZN sources. The growth time varied at 15, 60, 90, and 120 minutes after the zero-minute point. By using two separate and independent zinc sources while growing ZnO NRs at various growth periods, several ZnO NRs’ thicknesses were controlled. According to a paper by Lee et al., the lower thickness of ZnO NRs boosted the charge transfer properties of perovskite solar cells (PSCs) because the series resistance between ZnO/perovskite interfaces was lessened. Scanning electron microscopy (SEM) images were observed to analyze the morphological shape of the ZnO NRs. X-ray diffraction (XRD) profiles were characterized to obtain the data for ZnO NR crystallinity. Full width at half maximum (FWHM) analysis was performed at the (002) ZnO peak to calculate the crystal size of the peak. From the results, the smallest crystallite sizes for ZnO NRs grown from ZA and ZN sources were 10.70 nm and 19.29 nm, respectively, which would be the most suitable condition for PSC application.
Vertically well aligned zinc oxide (ZnO) nanorods have been developed for the application to photoanode of dye-sensitized solar cells (DSCs). For the growth of the ZnO nanorods, a seed layer is necessary. Spin coating and chemical bath deposition methods are chosen to form the seed layer and the ZnO nanorods, respectively. The effects of speed and cycle number of spin coating are investigated. The most optimized nanorods was found at seed layer with growing conditions of 3000 RPM rotational speed repeated for 3 times. The SEM image shows the longest length at 1.5 -2 m length while the XRD chart shows considerable peak at (002) crystallinity.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.