Influence of seed layer thickness on well-aligned ZnO nanorods via hydrothermal method

Pokai, S.; Limnonthakul, Puenisara; Horprathum, Mati; Eiamchai, Pitak; Pattantsetakul, V.; Limwichean, Saksorn; Nuntawong, Noppadon; Porntheeraphat, Supanit; Chitichotpanya, Chayanisa

doi:10.1016/j.matpr.2017.06.136

Cited by 18 publications

(8 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Moreover, when the particle size of seed layer increases the density of nucleation site decrease and therefore the number of nanorods per unit of surface area decreases, this is in good agreement with results shows in Figure 2b. The less density of nanorods with bigger diameter and better alignment, as show in Figure 1, promoted rapid growth along the vertical direction result in films of bigger thickness [34,35].…”

Section: Resultsmentioning

confidence: 99%

ZnO (Ag-N) Nanorods Films Optimized for Photocatalytic Water Purification

et al. 2019

View full text Add to dashboard Cite

ZnO nanorods (NRs) films, nitrogen-doped (ZnO:N), and ZnO doped with nitrogen and decorated with silver nanostructures (ZnO:N-Ag) NRs films were vertically supported on undoped and N doped ZnO seed layers by a wet chemical method. The obtained films were characterized structurally by X-ray diffraction. Morphological and elemental analysis was performed by scanning electron microscopy, including an energy dispersive X-ray spectroscopy facility and their optical properties by Ultraviolet-Visible Spectroscopy. Analysis performed in the NRs films showed that the nitrogen content in the seed layer strongly affected their structure and morphology. The mean diameter of ZnO NRs ranged from 70 to 190 nm. As the nitrogen content in the seed layer increased, the mean diameter of ZnO:N NRs increased from 132 to 250 nm and the diameter dispersion decreased. This diameter increase occurs simultaneously with the incorporation of nitrogen into the ZnO crystal lattice and the increase in the volume of the unit cell, calculated using the X-ray diffraction patterns and confirmed by a slight shift in the XRD angle. The diffractograms indicated that the NRs have a hexagonal wurtzite structure, with preferential growth direction along the c axis. The SEM images confirmed the presence of metallic silver in the form of nanoparticles dispersed on the NRs films. Finally, the degradation of methyl orange (MO) in an aqueous solution was studied by UV-vis irradiation of NRs films contained in the bulk of aqueous MO solutions. We found a significant enhancement of the photocatalytic degradation efficiency, with ZnO:N-Ag NRs film being more efficient than ZnO:N NRs film, and the latter better than the ZnO NRs film.

show abstract

Section: Resultsmentioning

confidence: 99%

ZnO (Ag-N) Nanorods Films Optimized for Photocatalytic Water Purification

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Since the diameter of the resulting nanorods was dependent on the average grain size of the seed layer, which was increased with an increase in the film thickness [ 24 , 25 , 26 ], an amorphous seed layer with a small grain size has become a very important research target to obtain nanorods with a larger surface-to-volume ratio. In this work, to achieve a high surface-to-volume ratio, high specific surface area, and more surface adsorption sites, the surface morphology was optimized by changing the thickness of the SnO 2 seed layer and the mixed solution concentration of the hydrothermal precursors.…”

Section: Resultsmentioning

confidence: 99%

Investigation of High-Sensitivity NO2 Gas Sensors with Ga2O3 Nanorod Sensing Membrane Grown by Hydrothermal Synthesis Method

Chu

Yeh

et al. 2023

Nanomaterials

View full text Add to dashboard Cite

In this work, Ga2O3 nanorods were converted from GaOOH nanorods grown using the hydrothermal synthesis method as the sensing membranes of NO2 gas sensors. Since a sensing membrane with a high surface-to-volume ratio is a very important issue for gas sensors, the thickness of the seed layer and the concentrations of the hydrothermal precursor gallium nitrate nonahydrate (Ga(NO3)3·9H2O) and hexamethylenetetramine (HMT) were optimized to achieve a high surface-to-volume ratio in the GaOOH nanorods. The results showed that the largest surface-to-volume ratio of the GaOOH nanorods could be obtained using the 50-nm-thick SnO2 seed layer and the Ga(NO3)3·9H2O/HMT concentration of 12 mM/10 mM. In addition, the GaOOH nanorods were converted to Ga2O3 nanorods by thermal annealing in a pure N2 ambient atmosphere for 2 h at various temperatures of 300 °C, 400 °C, and 500 °C, respectively. Compared with the Ga2O3 nanorod sensing membranes annealed at 300 °C and 500 °C, the NO2 gas sensors using the 400 °C-annealed Ga2O3 nanorod sensing membrane exhibited optimal responsivity of 1184.6%, a response time of 63.6 s, and a recovery time of 135.7 s at a NO2 concentration of 10 ppm. The low NO2 concentration of 100 ppb could be detected by the Ga2O3 nanorod-structured NO2 gas sensors and the achieved responsivity was 34.2%.

show abstract

“…The details of calculating the texture orientation of the Ag seed layer can be found elsewhere . After the seed layer preparation, the ZnO-NRs were grown through the seed-assisted hydrothermal process. ,,,,− The hydrothermal solution for ZnO-NRs growth was prepared via mixing zinc nitrate hexahydrate (Zn(NO 3 ) 2 ·6H 2 O) and hexamethylenetetramine (C 6 H 12 N 4 ) with an equal molar in the concentration range between 0.01 and 40 mM. The Ag seed layer with a different texture orientation of (111) plane (74.4–97.6%) was then immersed upside down into 50 mL of the growth solution in a sealed beaker with a typical growth temperature of 95 °C.…”

Section: Methodsmentioning

confidence: 99%

“…ZnO nanorods (ZnO-NRs) have been considered as promising building blocks for various applications such as light-emitting diodes, − organic/inorganic solar cells, − and spectroscopy signal enhancement platforms − due to their wide bandgap semiconductor with 60 meV binding energy at room temperature and a waveguide effect, where the hexagonal structures of ZnO-NRs can be attributed to the Fabry–Perot resonators (FPRs) with the end faces as reflecting mirrors . In the last few decades, the hydrothermal process has been widely appreciated comparing with other synthesis techniques such as the vapor–solid (VS) method, , vapor–liquid–solid (VLS) method, − and metal–organic chemical vapor deposition (MOCVD) , because of its low-temperature process ( T ≈ 95 °C), controllable diameter and position via seed crystals, and cost-effectiveness. − These allow us to integrate hydrothermal ZnO-NRs with various materials on organic substrates for biosensors, biomedical analysis, and flexible nanoelectronic devices. − A homogeneous ZnO seed layer has been frequently employed to control the morphological properties (e.g., density, diameter, and length) of ZnO-NRs. ,,− However, such a semiconducting characteristic of the ZnO homo-seed layer may not be applicable for electrical devices when direct low resistance electrical contact between the ZnO-NRs and the substrates is unavoidably required. , The directly contacted interface between the ZnO-NRs and noble metals, e.g., gold (Au), , silver (Ag), ,,,, and copper (Cu), is not only robust for electrical applications but also for the spectroscopy signal enhancement platform due to the localized surface plasmon resonance (LSPR) and high-reflectance properties of the noble metals and waveguide effect of ZnO-NRs. ,, ...…”

Section: Introductionmentioning

confidence: 99%

ZnO Nanorods Grown on Heterogenous Ag Seed Layers for Single-Cell Fluorescence Bioassays

Muensri

Treetong

Namdee

et al. 2021

ACS Appl. Nano Mater.

Self Cite

View full text Add to dashboard Cite

Here we demonstrate the controllability of the morphology of hydrothermal ZnO nanorods (ZnO-NRs) grown on heterogenous Ag seed layers. By varying the crystal orientation of silver thin films (Ag), a high density of ZnO-NRs could be obtained. We find that the density of ZnO-NRs strongly relates to the peak intensity ratio between (111) and (200) planes of Ag thin films due to a heteroepitaxy between (0002) ZnO and (111) Ag rather than that of grain boundary nucleation and/or surface nucleation. In addition, the optimized heterostructure of ZnO nanorod/Ag arrays is investigated via a critical concentration for nucleation and used as a fluorescence enhancement substrate (FES). The experimental results have shown that the FES presents an ability to detect a biological sample (PC-3 cell) with a high sensitivity and low detection limit of 1 cell/μL. Our results highlight that understanding an important key to control and design the morphology of heterogeneous hydrothermal ZnO-NR growth is essential to open up the opportunities for fundamental studies and applications in high-performance integrated nanodevices.

show abstract

Influence of seed layer thickness on well-aligned ZnO nanorods via hydrothermal method

Cited by 18 publications

References 4 publications

ZnO (Ag-N) Nanorods Films Optimized for Photocatalytic Water Purification

ZnO (Ag-N) Nanorods Films Optimized for Photocatalytic Water Purification

Investigation of High-Sensitivity NO2 Gas Sensors with Ga2O3 Nanorod Sensing Membrane Grown by Hydrothermal Synthesis Method

ZnO Nanorods Grown on Heterogenous Ag Seed Layers for Single-Cell Fluorescence Bioassays

Contact Info

Product

Resources

About