Size-Dependent Photoelectrochemical Properties of Nanostructured WO3 Thin Films Synthesized via Electrodeposition Method

2015 ◽  
Vol 1105 ◽  
pp. 269-273
Author(s):  
Tao Zhu ◽  
Meng Nan Chong ◽  
Eng Seng Chan
Keyword(s):  
Thin Films ◽  
Annealing Temperature ◽  
Unit Area ◽  
Annealing Treatment ◽  
Photocurrent Density ◽  
Sem Analysis ◽  
Photoelectrochemical Properties ◽  
Density Measurements ◽  
Size Dependent ◽  
Glass Working

The main aim of this study was to investigate size-dependent effect on the photoelectrochemical properties of nanostructured tungsten trioxide (WO3) thin films synthesized via electrochemical method. Firstly, the nanostructured WO3 thin films of different crystalline sizes were synthesized on fluorine-doped tin oxide (FTO) glass working electrodes followed by controlled annealing treatment at temperature of 100-600°C. The resultant nanostructured WO3 thin films were further characterized using field emission-scanning electron microscopy (FE-SEM) and photocurrent density measurements. Through FE-SEM analysis, it was found that the WO3 crystalline size increases with increasing annealing temperature that resulted in elevated photocurrent per unit area of the synthesized nanostructured WO3 thin films. Finally, it was observed that the highest photocurrent density of up to 35μA/cm2 was attained for WO3 crystallines size of 86nm that formed at the annealing temperature of 600°C.

A novel two-step strategy to fabricate phase-pure SnS photoelectrode with tunable conductivity: formation mechanism and photoelectrochemical properties

2021 ◽  
Author(s):  
Wenwan Zhang ◽  
Yufei Cheng ◽  
Junfeng Zhao ◽  
Qiujie Li ◽  
Jiawei Wang ◽  
...  
Keyword(s):  
Thin Films ◽  
Formation Mechanism ◽  
Photocurrent Density ◽  
Photoelectrochemical Properties ◽  
Secondary Phases ◽  
Injection Efficiency ◽  
Conductivity Type ◽  
Phase Pure ◽  
Sns Thin Films ◽  
Foil Substrate

Abstract Tin monosulfide (SnS), as a narrow band gap semiconductor for visible-light harvesting, nevertheless the easy formation of secondary phases such as Sn2S3 and SnS2 severely restricts its photoelectrochemical properties. Herein, we proposed a novel two-step strategy to fabricate phase-pure SnS photoelectrode with tunable conductivity on Ti foil substrate and carefully investigated the formation mechanism and photoelectrochemical properties. The tunable conductivity is determined by Na2SO4 pretreatment before annealing, which is supported by the EDS, XPS, and EPR characterizations. Na+ adsorbed to the edge of the precursor SnS2 nanosheets forming a dangling bond adsorption will protect S2- against reacting with the trace oxygen in the CVD system within a certain temperature range (< 525 ℃), thereby reducing the generation of S vacancies to adjust the S/Sn ratio and further regulating the conductivity type. Moreover, the anodic photocurrent density of SnS thin films was about 0.32 mA/cm2 at 1.23 V vs. RHE with the separation and injection efficiency of 1.22 % and 72.78 % and a maximum cathodic photocurrent density can reach approximately -0.36 mA/cm2 at 0 V vs. RHE with the separation and injection efficiency 1.15 % and 5.44 % respectively. The method shown in this work provides an effective approach to control the electrical conductivity of SnS thin films with considerable photocurrent response for phase-pure SnS.

scholarly journals Effect of rapid thermal annealing on structural and optical properties of ZnS thin films fabricated by RF magnetron sputtering technique

2019 ◽  
Vol 14 (1) ◽  
pp. 53-63 ◽  
Author(s):  
M. S. Bashar ◽  
Rummana Matin ◽  
Munira Sultana ◽  
Ayesha Siddika ◽  
M. Rahaman ◽  
...  
Keyword(s):  
Thin Films ◽  
Magnetron Sputtering ◽  
Carrier Concentration ◽  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Annealing Temperature ◽  
Annealing Treatment ◽  
Localized States ◽  
Stoichiometric Ratio ◽  
Deposited Films

AbstractThe ZnS thin films have been deposited by radio frequency magnetron sputtering at room temperature. Post-deposition rapid thermal annealing treatment was done for the films deposited at different powers ranging from 70 to 100 W. One peak is observed for as-deposited and annealed thin films at around 28.48° corresponding to the (111) reflection plane indicating a zincblende structure. The overall intensity of the peaks and the FWHM values of as-deposited films increased after annealing corresponding to the increase in crystallinity. The optical energy bandgap is found in the range of 3.24–3.32 eV. With increasing annealing temperature, the decrease in the Urbach energy values indicating a decrease in localized states which is in good agreement with the XRD results where the crystallinity increased. The surface morphology of the films seems to be composed of Nano-granules with a compact arrangement. Apparently, the grain size increases in the deposited films as annealing temperature increases. The compositional ratio attained close to the stoichiometric ratio of 1:1 after annealing. From the Hall effect measurement, the carrier concentration and mobility are found to increase after annealing. The high carrier concentration and mobility also comply with structural and optical analysis. Best results are found for the film annealed at 400 °C deposited at 90 W.

Defect-Related Photoluminescence from SiO2 Thin Films by Si-Ge Ions Doped

2011 ◽  
Vol 328-330 ◽  
pp. 1153-1156 ◽  
Author(s):  
Kun Zhong ◽  
Yan Dong Xia ◽  
Ju Hong Miao ◽  
Jiang Fu
Keyword(s):  
Thin Films ◽  
Photoelectron Spectroscopy ◽  
Annealing Temperature ◽  
Annealing Treatment ◽  
X Ray Diffraction ◽  
X Ray

Si and Ge ions are implanted into SiO2thin films, subsequently the annealing treatment are carried out. The samples exhibit photoluminescence (PL) peaks at 400, 470, 550 and 780 nm. With the annealing temperature increasing, the intensity of 400-470 nm PL band increases remarkably. After oxidation annealing treatment, the intensity of 400-470 nm PL band decreases, and that of 550 nm and 780 nm PL peaks rises. Combing with the results of X-ray photoelectron spectroscopy(XPS), X-ray diffraction (XRD) and PL measurement, we propose that the PL peaks at 400 nm, 470 nm, 550 nm and 780 nm originate from ≡Ge−Si≡ center, ≡Si−Si≡ center, SPR center and GeO center, respectively.

scholarly journals Influence of Annealing Temperature on the Properties of ZnGa2O4 Thin Films by Magnetron Sputtering

Coatings ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 859 ◽  
Author(s):  
Wei-Kai Wang ◽  
Kuo-Feng Liu ◽  
Pi-Chuen Tsai ◽  
Yi-Jie Xu ◽  
Shih-Yung Huang
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Magnetron Sputtering ◽  
Thermal Annealing ◽  
Annealing Temperature ◽  
Annealing Treatment ◽  
Average Crystallite Size ◽  
Thin Film Deposition ◽  
Film Deposition ◽  
Atmospheric Conditions

Zinc gallate (ZnGa2O4) thin films were grown on sapphire (0001) substrate using radio frequency (RF) magnetron sputtering. After the thin film deposition process, the grown ZnGa2O4 was annealed at a temperature ranging from 500 to 900 °C at atmospheric conditions. The average crystallite size of the grown ZnGa2O4 thin films increased from 11.94 to 27.05 nm as the annealing temperature rose from 500 to 900 °C. Excess Ga released from ZnGa2O4 during thermal annealing treatment resulted in the appearance of a Ga2O3 phase. High-resolution transmission electron microscope image analysis revealed that the preferential crystallographic orientation of the well-arranged, quasi-single-crystalline ZnGa2O4 (111) plane lattice fringes were formed after the thermal annealing process. The effect of crystallite sizes and lattice strain on the width of the X-ray diffraction peak of the annealed ZnGa2O4 thin films were investigated using Williamson-Hall analysis. The results indicate that the crystalline quality of the deposited ZnGa2O4 thin film improved at higher annealing temperatures.

Influence of Annealing Treatment on N-Doped TiO2 Films Deposited by Pulsed Negative Bias Arc Ion Plating

2012 ◽  
Vol 482-484 ◽  
pp. 1105-1110
Author(s):  
Shu Juan Zhang ◽  
Ming Sheng Li ◽  
Zhi Qin Chen ◽  
Yong Zhong Fan
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Annealing Temperature ◽  
Annealing Treatment ◽  
Catalytic Performance ◽  
Film Structure ◽  
Negative Bias ◽  
Arc Ion Plating ◽  
Ion Plating ◽  
Absorption Edges

The N-doped TiO2thin films were deposited on medical glass slide by pulsed negative bias arc ion plating. The influence of pulsed negative bias, annealing temperature and time on films properties was investigated. Film structure, surface morphologies and optical properties were measured with XRD, SEM and UV-VIS transmittance spectroscope. Photo-catalytic performance of the films was evaluated by degrading methyl orange. The results show that the absorption edges of the as-deposited films increase with the rising of the pulse negative bias, and the maximum of 550 nm is achieved under -600V bias. The films absorption edges increase in different degree after annealing at 400°Cand 500°Cfor 2h, and the best extending can increase 22nm after annealing. The diffraction peak intensity and surface grain size increase with increasing the annealing temperature and time. The grain size of films after annealing at 400°C for 4h is largest of all the films. The pulsed negative bias and annealing treatment not only indecrease TiO2thin films the UV catalytic performance, but also extend the catalytic properties to the sunlight.

Effects of Annealing Treatment on WO3 Thin Films Prepared by DC Reactive Magnetron Sputtering

2014 ◽  
Vol 979 ◽  
pp. 248-250 ◽  
Author(s):  
Thanat Srichaiyaperk ◽  
Kamon Aiempanakit ◽  
Mati Horprathum ◽  
Pitak Eiamchai ◽  
Chanunthorn Chananonnawathorn ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Optical Properties ◽  
Magnetron Sputtering ◽  
Film Thickness ◽  
Annealing Temperature ◽  
Annealing Treatment ◽  
Reactive Magnetron ◽  
Thin Film Thickness ◽  
Dc Reactive Magnetron Sputtering

Tungsten trioxide (WO3) thin films were prepared by a DC reactive magnetron sputtering technique. The thin film fabrication process used tungsten (99.995%) as the sputtering target, the mixture of argon and oxygen as sputtering and reactive gases, and silicon (100) and glass slides as the substrates. The effects of annealing temperature in the range of 200-400°C on physical and optical properties of the WO3 thin films were investigated. The nanostructures and morphologies of these films were characterized by grazing-incident X-ray diffraction (GIXRD) and field-emission scanning electron microscopy (FE-SEM). The optical properties were analyzed by variable-angle spectroscopic ellipsometry (VASE) and spectrophotometer. From the XRD results, the as-deposited and annealed WO3 thin films up to 300°C were all amorphous. Only the WO3 thin film annealed at 400°C exhibited a polycrystalline monoclinic phase. The FE-SEM cross-sections and surface topologies demonstrated nearly identical thin-film thickness and physical grain sizes. The SE analyses showed that the thin films were all homogeneous dense layers with additional surface roughness. With the annealing treatment, the thin film thickness was slightly decreased. The SE physical model was best optimized with the Cauchy optical model. The results showed that the refractive index at 550 nm was increased from 2.17 to 2.23 with the increased annealing temperature. The results from the spectrophotometer confirmed that the optical spectra for the WO3 thin films were decreased. This study demonstrated that, the thin film annealed at 400°C exhibited the slightly lower transparency, which corresponded to the results from the GIXRD and SE analyses.

The Ferroelectric Characteristics of Ba(Zr0.1Ti0.9)O3 Thin Films under Post-Annealing Treatment for Applications in Nonvolatile Memory Devices

2011 ◽  
Vol 239-242 ◽  
pp. 895-898
Author(s):  
Kai Huang Chen ◽  
Jen Hwan Tsai ◽  
Chia Lin Wu ◽  
Jian Yang Lin ◽  
Chien Min Cheng
Keyword(s):  
Thin Films ◽  
Memory Effect ◽  
Current Density ◽  
Nonvolatile Memory ◽  
Annealing Temperature ◽  
Ferroelectric Properties ◽  
Annealing Treatment ◽  
Metal Insulator ◽  
Post Annealing ◽  
Nonvolatile Memory Devices

In this study, we investigated that of Al/ Ba(Zr0.1Ti0.9)O3(BZT)/Pt/Ti/SiO2/Silicon metal-ferroelectric-metal-insulator-semiconductor (MFM) ferroelectric structures and found the memory effect and capacitance of annealed BZT films during the different annealing temperature. Additionally, the capacitance and leakage current density were about 4.3 nF and 1´10-6A/cm2, respectively. From C-V curves, the ferroelectric properties and charges accumulation of annealed BZT films were also found during the annealing temperature of 700°C.

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