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1.
Wiranwetchayan Orawan Ruankham Pipat Promnopas Wonchai Choopun Supab Singjai Pisith Chaipanich Arnon Thongtem Somchai 《Journal of Solid State Electrochemistry》2018,22(8):2531-2543
Journal of Solid State Electrochemistry - A simple and inexpensive sparking method was used to deposit body-centered cubic In2O3 film on TiO2 photoanode for 30–180 min for... 相似文献
2.
FD Reis JP Badiali D di Caprio 《Langmuir : the ACS journal of surfaces and colloids》2012,28(36):13034-13041
Nanostructured porous oxides are produced by anodic dissolution of several metals. A scaling approach is introduced to explain pattern nucleation in an oxide layer, and a related microscopic model shows oxide growth with long nanopores. The scaling approach matches the time of ion transport across the thin oxide layer, which is related to metal corrosion, and the time of diffusion along the oxide/solution (OS) interface, which represents the extension of oxide dissolution. The selected pattern size is of order (dD(S)/v(O))(1/2), where d is the oxide thickness, v(O) is the migration velocity of oxygen ions across the oxide, and D(s) is the diffusion coefficient of H(+) ions along the oxide/solution interface. This result is consistent with available experimental data for those quantities, predicts the increase of pore size with the external voltage, and suggests the independence of pore size with the solution pH. Subsequently, we propose a microscopic model that expresses the main physicochemical processes as a set of characteristic lengths for diffusion and surface relaxation. It shows a randomly perturbed OS interface at short times, its evolution to pore nucleation and to stable growth of very long pores, in agreement with the mechanistic scenario suggested by two experimental groups. The decrease of the size of the walls between the pores with the interface tension is consistent with arguments for formation of titania nanotube arrays instead of nanopores. These models show that pattern nucleation and growth depend on matching a small number of physicochemical parameters, which is probably the reason for the production of nanostructured porous oxides from various materials under suitable electrochemical conditions. 相似文献
3.
The present work reports the enhancement of the photoelectrochemical water splitting performance of in-situ silicon (Si)-doped nanotubular/nanoporous (NT/NP) layers. These layers were grown by self-organizing anodization on Fe-Si alloys of various Si content. The incorporation of Si is found to retard the layer growth rates, leads to a more pronounced nanotubular morphology, and most importantly, an improved photoelectrochemical behavior. By increasing Si content from 1, 2 to 5 at.% in the iron oxide NT/NP photoanodes, the photocurrent onset potential shifts favorably to lower values. At 1.3 V vs. RHE, hematite layer with 5 at.% Si shows a 5-fold increase of the photocurrent, i.e. 0.5 mA cm− 2 in comparison to 0.1 mA cm− 2 for the undoped samples. The study also reveals that a suitable layer thickness is essential to achieve a beneficial effect of the Si doping. 相似文献
4.
Due to the involvement of four-electron transfer process at photoanode,water oxidation is the ratelimiting step in water splitting reaction.To settle this dilemma,ZnCo2 O4 nanoparticles are combined with BiVO4 to form a p-n ZnCo2 O4/BiVO4 heterojunction photoanode,which is proved by an input voltage-output current test.The built-in electric field formed within the heterojunction structure promotes the effective separation of elect... 相似文献
5.
A class of nanoporous TiO2 gas sensors processed by novel anodic aluminum oxidation (AAO) of Al thin films and microelectromechnical systems (MEMS) techniques are presented. To enhance the sensitivity and reduce the sensing dimensions of a gas sensor, a nanoporous surface of the gas-sensitive material on the sensor is required. These sensors can be implemented on silicon or silicon dioxide substrate featuring a thin membrane of micro-hotplate structure featuring micro-heaters, thermometers and electrodes, and thus operate as chemoresistive devices. Combining the AAO method with dry-etch process, a homogeneous and nanoporous SiO2 surface of the sensor can be effectively configured by modulating various hole diameters and depth, hence replacing conventional photolithography and electrochemical etch. The process integration including AAO, reactive ion etch (RIE) and microfabrication is mainly developed and a feasibility study of PVD TiO2 thin film deposition upon the porous device is also provided. TiO2 thin films deposited on the nanoporous surface are investigated and compared with non-porous TiO2 films. It is encouraging that our fabrication process is able to provide relatively high surface area to enhance sensitivity of the sensor without additional doping steps. Our promising experimental results have revealed these miniature and cost-effective devices are not only compatible, but applicable to smart bio-chemical sensors of next generation. 相似文献
6.
《印度化学会志》2023,100(8):101070
The Bi2O3 and reduced graphene (RG)-Bi2O3 nano-composite thin films are synthesized using modified sol-gel process. For structural examination, the samples are analyzed using XRD. Using the Scherrer equation and a modified Scherrer plot, the sample's structural parameters are calculated. The materials' size and strain were estimated from different methods like modified Williamson-Hall (W–H), Halder-Wagner (H–W), and Size Strain Plot (SSP) with logical validity. The different crystallographic parameters obtained are compared and presented in this work. 相似文献
7.
Cha HG Song J Kim HS Shin W Yoon KB Kang YS 《Chemical communications (Cambridge, England)》2011,47(8):2441-2443
We report a simple approach for preparing undoped and Pt-doped Fe(2)O(3) thin films with excellent photoactivity via facile hydrothermal growth. The photocurrent densities of undoped and Pt-doped Fe(2)O(3) thin films were recorded up to 1.2 and 1.38 mA cm(-2) at 0.23 V Ag/AgCl under 1 sun illumination, respectively. 相似文献
8.
Facile Fabrication of Porous Bi2O3 Microspheres by Thermal Treatment of Bi2O2CO3 Microspheres and its Photocatalysis Properties 总被引:1,自引:0,他引:1
Gangqiang Zhu Jia Lian Mirabbos Hojamberdiev Wenxiu Que 《Journal of Cluster Science》2013,24(3):829-841
β- and α-phase porous Bi2O3 microspheres with an average size of around 4 μm had been synthesized by thermal treatment of Bi2O2CO3 microspheres at 350 and 400–500 °C respectively in an air atmosphere. The Bi2O2CO3 microspheres had been synthesized at a temperature of 180 °C by a hydrothermal process using Bi(NO3)3 as the bismuth source with the assist of citric acid. By combining the results of X-ray powder diffraction, transmission electron microscope, scanning electron microscopy, and UV–Visible absorption spectra, the structural, morphological and optical properties characterization of the products were performed. The photocatalytic activity of the as-prepared α- and β-phase porous Bi2O3 microspheres have been tested by degradation of methylene orange under visible light, indicating that porous β-Bi2O3 microspheres showed enhanced photocatalytic performance compared to P25 and α-Bi2O3 microspheres. 相似文献
9.
Junsong Yang Juanjuan Zhao Hailong Wang Shengyi Zhang Jiming Song Changjie Mao Helin Niu Baokang Jin Yupeng Tian 《Journal of Sol-Gel Science and Technology》2013,67(3):660-664
By dipping-lifting in sol–gel solution and reducing process, the TiO2 composite film on the glass plate was first prepared. Then, the PbSe/BaTiO3/TiO2 composite film was fabricated by interface reaction with BaTiO3 and PbSe on the surface of TiO2 composite film. The characterization results show that the uniform porous TiO2 film is made up of the anatase crystal, and the PbSe/BaTiO3/TiO2 composite film is constructed by doping or depositing BaTiO3 and PbSe nanoparticles on the surface of TiO2 film. The photoelectrochemical measurement results indicate that the PbSe/BaTiO3/TiO2 composite film has an interesting photoelectrochemical conversion property. 相似文献
10.
Ambre S. K. Patil S. S. Bhat T. S. Patil P. S. 《Journal of Solid State Electrochemistry》2023,27(2):337-343
Journal of Solid State Electrochemistry - Bismuth sulfide (Bi2S3)-sensitized titanium dioxide (TiO2) nanorods have been successfully synthesized by a simple and cost-effective chemical deposition... 相似文献
11.
《Arabian Journal of Chemistry》2020,13(12):9166-9178
The current work investigates the morphology, crystallinity and photoelectrochemical (PEC) performance of bismuth sulfide/silver sulfide/zinc oxide nanorods (Bi2S3/Ag2S/ZnO NRAs) photoelectrodes as prepared at different annealing temperature. ZnO NRAs was initially grown hydrothermally, deposited in sequence with Ag2S and Bi2S3 via successive ionic layer adsorption and reaction (SILAR) method before undergoing the annealing treatment. The optimised photoelectrode (Bi2S3/Ag2S/ZnO NRAs-400 °C) possesses an optical bandgap of 1.60 eV extending the absorption edge of ZnO to visible light spectrum. The current-voltage characterization of Bi2S3/Ag2S/ZnO NRAs photoelectrodes revealed that the photocurrent density and photoconversion efficiency were strongly dependent on the annealing temperature. The PEC study shows that the photoelectrode annealed at 400 °C achieved impressive photocurrent density of 12.95 mA/cm2 at +0.5 V (vs Ag/AgCl/saturated KCl) under 100 mW/cm2 illumination with superior photoconversion efficiency of 12.63%. This improvement is due to the cascade-designed band structure alignment of Bi2S3/Ag2S/ZnO/ITO and to the brilliant role of Ag2S as an intermediate layer that reduced random chance of electron-hole (e−-h+) pairs recombination and improved the electrons collection efficiency. This work is highly anticipated to give contribution on further utilisation of Bi2S3/Ag2S/ZnO NRAs as a promising semiconductor material in PEC related applications. 相似文献
12.
Bi5Nb3O15 was prepared from a stoichiometric mixture of Bi2O3 and Nb2O5 at 300–500 °C. The prepared photocatalyst was characterized by diffuse reflection spectrum (DRS), X-ray diffraction (XRD),
scanning electron microscopy (SEM) and particle size analysis. The band gap, crystal structure and average grain size were
determined from the above methods to be 3.25 eV, distorted pyrochlore and 4–5 μm respectively. The photoelectrochemical behavior
of hydrogen-reduced Bi5Nb3O15 was investigated in 0.1 M Na2SO4 and using the Fe(CN)6
3−/4− redox couple for measuring the current-voltage characteristics. The cyclic voltammetric studies revealed that the onset potential
for photocurrent generation existed at −0.45 V, which is more negative to water reduction level at pH 7.0, and that of the
photocurrent at 1.0 V was observed as 0.58 mA/cm2. Photocatalytic hydrogen production has been achieved by using Bi5Nb3O15 as a photocatalyst in presence of methyl viologen. The quantum yield for hydrogen production for this system was found to
be 0.83. All the studies clearly indicated that Bi5Nb3O15 has potential in solar energy conversion.
Received: 22 May 1997 / Accepted: 18 September 1997 相似文献
13.
Aleksey A. Yaremchenko Vladislav V. Kharton Evgeny N. Naumovich Anneta A. Tonoyan Viktor V. Samokhval 《Journal of Solid State Electrochemistry》1998,2(5):308-314
Electrical conductivity, fluorite-type cubic unit cell volume and thermal expansion of the (Bi1−
x
Nb
x
)1−
y
Ho
y
O1.5+δ (x=0.05 and 0.08; y=0.10−0.15) and (Bi1−
x
Zr
x
)1−
y
Y
y
O1.5+δ (x=0.05 and 0.07; y=0.15) solid solutions have been found to decrease regularly with increasing dopant content. Annealing at temperatures below
900 K leads to a phase decomposition and to a sharp decrease in conductivity of the ceramics. Oxygen ion transference numbers
have been determined by the e.m.f. method and by Faradaic efficiency measurement to exceed 0.9. A new technique of studying
Faradaic efficiency has been proposed and verified using (Bi0.95Zr0.05)0.85Y0.15O1.5+δ and Zr0.90Y0.10O1.95 ceramic samples.
Received: 31 October 1997 / Accepted: 18 December 1997 相似文献
14.
Oxidation resistance of metal at high temperature can be improved by an environmentally friendly solution deposition approach.
Stable precursor solution with high oxide concentration, favorable viscosity and low surface tension was prepared using aluminum
sec-butoxide (ASB) and polyvinylpyrrolidone (PVP) as starting raw materials. Alumina sol-gel films were deposited onto metal
by spin-coating followed by heat treatment. When PVP was added according to an amount of 50 mg/mL into a sol with an ASB/H2O molar ratio of 1:35, the as-obtained sol exhibited favorable gelation time and viscosity. The surface tension of the alumina
sol with PVP was examined to be lower by 32% than the sol (ASB:H2O = 1:100) without PVP. TG-DTA analyses show the densification of the alumina gel film with PVP was progressed within a wide
temperature range from 200 to 650 °C. Crack-free Al2O3 film with a thickness up to 1.5 μm was successfully produced on metallic substrate by three spin-coating cycles. SEM and
XRD analyses revealed the gel film transformed into compact α-Al2O3 material after calcined at 1,000 °C for 0.5 h. The weight gained by the samples during firing at 1,000 °C indicated that
the Al2O3 coating film could reduce the rate of oxidation by ∼81%. The hardness of the Al2O3 film coated metal was higher by 260% than the uncoated metal that was calcined at 1,000 °C for 0.5 h. It was confirmed by
adhesion test that both the alumina/PVP hybrid film and the as-produced α-Al2O3 coating film had strong adhesion. 相似文献
15.
J. C. Calva-Yáñez M. E. Rincón M. Solís de la Fuente G. Alvarado-Tenorio 《Journal of Solid State Electrochemistry》2013,17(10):2633-2641
Structural and photoelectrochemical characterization of multiwall carbon nanotubes–titanium oxide (MWCNT-TiO2) matrices, sensitized with bismuth sulfide (Bi2S3), are presented as a function of MWCNT-TiO2 annealing temperature and Bi2S3 deposition time. Random matrices of multiwall carbon nanotubes were grown on stainless steel substrates by spray pyrolysis and then functionalized with a thin layer of TiO2. Air annealing modifies the morphology and C/TiO2 ratio in the hybrid materials, from MWCNT-TiO2 core and shell structures at 400 °C to carbon-doped TiO2 (C-TiO2) at 550 °C. Both matrices increase the amount of Bi2S3 deposited by the chemical bath, but the best photoelectrochemical performance is observed in electrodes based on C-TiO2. Electrodes based on core–shell structures of MWCNT-TiO2 show large capacitive currents that interfere with photocurrent generation, demonstrating the storage potential of MWCNT and the critical role of MWCNT/TiO2 ratio for photoelectrochemical applications. Regardless of the superior properties of C-TiO2 photoanodes, the power conversion efficiency of Bi2S3-sensitized C-TiO2 is limited by the appearance of an electron collection barrier at the substrate/film interface. 相似文献
16.
Tien The Nguyen Thang Minh Le Duc Duc Truong Rasmus Fehrmann Anders Riisager Isabel Van Driessche 《Research on Chemical Intermediates》2012,38(3-5):829-846
In this work, the possible synergy effects between Bi2O3, MoO3 and V2O5, and between Bi2Mo3O12 and BiVO4, were investigated. The catalytic activity of the ??mechanical mixture?? of these compounds was measured. The mixture containing 36.96?mol% Bi2O3, 39.13?mol% MoO3 and 23.91?mol% V2O5 (21.43?mol% Bi2Mo3O12 and 78.57?mol% BiVO4), corresponding to the compound Bi1?x/3V1?x Mo x O4 with x?=?0.45 (Bi0.85V0.55Mo0.45O4), exhibited the highest activity for the selective oxidation of propylene to acrolein. The mixed sample prepared chemically by a sol?Cgel method possessed higher activity than that of mechanical mixtures. 相似文献
17.
18.
Petra Šulcová Lenka Stránská Eva Proklešková 《Journal of Thermal Analysis and Calorimetry》2013,113(3):1203-1208
A series of novel environmentally inorganic pigments based on Bi2O3 doped by metal ion Dy3+ has been developed and characterized using methods of thermal analysis, X-ray powder diffraction and by reflectance spectral data. The new pigments have been synthesized from mixtures containing Bi2O3 and Dy2O3 by traditional solid-state route. The incorporation of Dy3+ into crystal lattice Bi2O3 changes the colour from yellow-orange to orange. The band gap of phases with formula Bi2?xDyxO3, where x = 0.8, increases from 2.30 to 2.38 eV with growth of calcination temperature. The pigment Bi1.2Dy0.8O3 was also evaluated from the standpoint of influence of milling time on the colour properties and particle size. The simultaneous TG–DTA measurements were used for determination of the temperature region of the pigment formation and thermal stability of pigments. The results confirm the positive effect of lanthanide ions into Bi2O3 on thermal stability of prepared phases. 相似文献
19.
We present a novel electrochemical approach to grow copper phthalocyanine (CuPc) thin-film photoelectrodes through anodic oxidation of copper and dilithium phthalocyanine (Li2Pc). This circumvents the challenges associated with the electrochemical processing of unsubstituted CuPc from solution. The potentiostatic co-electrooxidation reaction at the heterogeneous interface favors the growth of CuPc thin film. The surface morphology of thin film exhibits nanorod-like features. UV-Vis, grazing angle Fourier transform infrared (FTIR), and grazing angle X-ray diffraction patterns reveal that the nanocrystalline phase corresponds only to α-CuPc and no admixture of other polymorphs. Photocurrent measurement shows a stable photoresponse in neutral medium. The photoelectrochemical hydrogen evolution on p-type CuPc coated copper photocathode shows an enhanced activity over bare copper and indium tin oxide (ITO) electrodeposited with CuPc and monolithium phthalocyanine radical (LiPc) thin films. 相似文献
20.
Sm对MoO3-Bi2O3催化剂性能的影响 总被引:1,自引:0,他引:1
在MoO3-B i2O3催化剂中加入稀土氧化物Sm2O3,在固定床反应器中考查了Sm2O3添加量、反应温度、异丁烯浓度、原料气流量等对异丁烯转化为甲基丙烯醛反应的影响。实验表明,添加Sm2O3可明显提高异丁烯的转化率和甲基丙烯醛的选择性。用XRD技术研究了催化剂的组成,Mo-B i-O催化剂的成分主要是B i2O3和MoO3的混合物,添加Sm后出现了Sm2Mo3O12的衍射峰,且衍射峰的强度随着Sm添加量的增加而增强。 相似文献