Decreased Surface Photovoltage of ZnO Photoanode Films via Optimal Annealing Temperature for Enhanced Photoelectrochemical Performance

The electronic structure of semiconducting materials at the electrode/electrolyte interface plays a vital role in the process of photoelectrochemical (PEC) water splitting. In this work, we could reliably tune the surface defect density of ZnO films through changing the annealing temperature, thereby optimizing the PEC performance. The surface photovoltage (SPV) of ZnO films could be obtained by Kelvin probe force microscopy and compared to insightfully understand the effect of the annealing temperature on the performance of the electrode in PEC water splitting. The minimum SPV annealed at 450°C indicated low surface defect density, eventually resulting in an enhanced photoelectrochemical performance. The applied bias photo-to-current efficiency of ZnO films annealed at 450°C reached 0.237%, about 7.4 times that of unannealed ZnO photoanode. This work provides an effective method for the rational fabrication of efficient photoelectrodes for the realization of high-performance photoelectrochemical water splitting.

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Ni/Si-Codoped TiO2 Nanostructure Photoanode for Enhanced Photoelectrochemical Water Splitting

Materials ◽

10.3390/ma12244102 ◽

2019 ◽

Vol 12 (24) ◽

pp. 4102 ◽

Cited By ~ 6

Author(s):

Ting Li ◽

Dongyan Ding

Keyword(s):

Water Splitting ◽

Annealing Temperature ◽

Photocurrent Density ◽

Electrochemical Anodization ◽

Codoped Tio2 ◽

Lower Charge ◽

Si Doped ◽

Tio2 Nanostructures ◽

Tio2 Photoanode ◽

Pec Water Splitting

We synthesized Ni/Si-codoped TiO2 nanostructures for photoelectrochemical (PEC) water splitting, by electrochemical anodization of Ti-1Ni-5Si alloy foils in ethylene glycol/glycerol solutions containing a small amount of water. The effects of annealing temperature on PEC properties of Ni/Si-codoped TiO2 photoanode were investigated. We found that the Ni/Si-codoped TiO2 photoanode annealed at 700 °C had an anatase-rutile mixed phase and exhibited the highest photocurrent density of 1.15 mA/cm2 at 0 V (vs. Ag/AgCl), corresponding to a photoconversion efficiency of 0.70%, which was superior to Ni-doped and Si-doped TiO2. This improvement in PEC water splitting could be attributed to the extended light absorption, faster charge transfer, possibly lower charge recombination, and longer lifetime.

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Controlling the Cytotoxicity of CdSe Magic-Sized Quantum Dots as a Function of Surface Defect Density

Nano Letters ◽

10.1021/nl5028028 ◽

2014 ◽

Vol 14 (9) ◽

pp. 5452-5457 ◽

Cited By ~ 21

Author(s):

Anielle Christine Almeida Silva ◽

Marcelo José Barbosa Silva ◽

Felipe Andrés Cordero da Luz ◽

Danielle Pereira Silva ◽

Samantha Luara Vieira de Deus ◽

...

Keyword(s):

Quantum Dots ◽

Surface Defect ◽

Defect Density ◽

Surface Defect Density

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Highly improved electrical and photoelectrical properties of electro-deposited p-type cuprous oxide

Functional Materials Letters ◽

10.1142/s1793604720510492 ◽

2020 ◽

Vol 13 (08) ◽

pp. 2051049

Author(s):

G. Wu ◽

Y. Zhang ◽

W. Zhang ◽

D. Jin ◽

L. Wang

Keyword(s):

Cuprous Oxide ◽

Surface Defect ◽

Annealing Temperature ◽

Defect Density ◽

Lower Surface ◽

Flat Band ◽

Electrical And Optical Properties ◽

Text Type ◽

Photoelectrical Properties ◽

P Type

In this work, the effect of annealing on the electrical and optical properties of electro-deposited [Formula: see text]-type cuprous oxide was studied in detail. It is found that the flat band potential linearly increased with annealing temperature and the carrier concentration was improved from 6.56 × 10[Formula: see text] cm[Formula: see text] to 23.3 × 10[Formula: see text] cm[Formula: see text]. The photocurrent intensity of cuprous oxide was improved from 12.1 [Formula: see text]A to 106.6 [Formula: see text]A after annealing. The dramatically improved electrical and photoelectrical properties might be ascribed to the highly improved crystallinity and the lower surface defect density caused by annealing.

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NaTaO3 Photoanode for Bias-Free Water Splitting: A Photo-Electrochemical and Kelvin Probe Surface Photovoltage Study

The Journal of Physical Chemistry C ◽

10.1021/acs.jpcc.6b07247 ◽

2016 ◽

Vol 120 (41) ◽

pp. 23559-23565 ◽

Cited By ~ 5

Author(s):

Leo Polak ◽

Jan H. Rector ◽

Martin J. Slaman ◽

Rinke J. Wijngaarden

Keyword(s):

Water Splitting ◽

Free Water ◽

Surface Photovoltage ◽

Kelvin Probe ◽

Probe Surface

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Controllable synthesis of CdS/WO3 heterostructures with enhanced photoelectrochemical performance

RSC Advances ◽

10.1039/c5ra23765c ◽

2016 ◽

Vol 6 (20) ◽

pp. 16668-16672 ◽

Cited By ~ 13

Author(s):

Yi Liu ◽

Yingde Cui ◽

Feiyan Huang ◽

Xinzhe Yang

Keyword(s):

Water Splitting ◽

Environmental Problems ◽

Controllable Synthesis ◽

Photoelectrochemical Performance ◽

Pec Water Splitting

With the increasing energy and environmental problems, photoelectrochemical (PEC) water splitting has recently attracted a great deal of attention.

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PREPARATIONS OF ZINC OXIDES AND CHARACTERIZATION OF THE PHOTOVOLTAIC BEHAVIOR USING A SCANNING KELVIN PROBE

Surface Review and Letters ◽

10.1142/s0218625x10014272 ◽

2010 ◽

Vol 17 (05n06) ◽

pp. 451-455

Author(s):

Y. HE ◽

W. ZHI ◽

B. O. ZHOU

Keyword(s):

Energy Level ◽

Level Structure ◽

Surface Photovoltage ◽

Zno Films ◽

Semiconductor Films ◽

Kelvin Probe ◽

Energy Level Structure ◽

Scanning Kelvin Probe ◽

Photovoltaic Behavior

Surface photovoltage of semiconductors depend strongly on their electronic structures, in particular, their Fermi energy level. This offers a possibility to characterize photoelectronic behavior using the Kelvin probe structure by measurements of work function (WF). In this paper, ZnO films were prepared using the CVD method and their microstructures and morphology were characterized using the XRD and SEM. Furthermore, photovoltage evolution and WF of selected ZnO samples were measured using a scanning Kelvin probe (SKP) system. It is found that the surface photovoltage and its time-resolved evolution process as well as the energy level structure of ZnO films can be correlated to WF very well. The present study therefore provides a simple and practical methodology for the characterization of photovoltaic behavior of semiconductor films.

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Influence of aspect ratio and surface defect density on hydrothermally grown ZnO nanorods towards amperometric glucose biosensing applications

Applied Surface Science ◽

10.1016/j.apsusc.2017.06.119 ◽

2017 ◽

Vol 422 ◽

pp. 798-808 ◽

Cited By ~ 19

Author(s):

Mayoorika Shukla ◽

Pramila ◽

Tejendra Dixit ◽

Rajiv Prakash ◽

I.A. Palani ◽

...

Keyword(s):

Aspect Ratio ◽

Surface Defect ◽

Defect Density ◽

Zno Nanorods ◽

Glucose Biosensing ◽

Surface Defect Density

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Deposition, Defect and Weak Bond Formation Processes in a-Si:H

MRS Proceedings ◽

10.1557/proc-507-897 ◽

1998 ◽

Vol 507 ◽

Cited By ~ 3

Author(s):

J Robertson ◽

M J Powell

Keyword(s):

Hydrogen Evolution Reaction ◽

Surface Defect ◽

Defect Formation ◽

Defect Density ◽

Bond Formation ◽

Surface Processes ◽

Formation Processes ◽

Weak Bond ◽

Further Development ◽

Surface Defect Density

ABSTRACTThe growth of a-Si:H and the resulting weak bond and defect formation mechanism is analysed in terms of the adsorbed Sill3 model of growth. It is found that this model describes the surface processes well, but it needs further development to correctly describe the temperature dependence of the formation of defects and weak bonds, since the surface defect density decreases monotonically with temperature and does not show a minimum near 250C. We show that the experimentally observed increase in hydrogen content, weak bond and defect density at lower deposition temperatures can be accounted for by a hydrogen evolution reaction from H2* sites.

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LaTiO2N nanopowders (NPs) with low surface defect density via nitridation of flame made NPs retaining simple perovskite structure

Dalton Transactions ◽

10.1039/d1dt03687d ◽

2022 ◽

Author(s):

Yoshiyuki Abe ◽

Richard M. Laine

Keyword(s):

Optical Absorption ◽

Absorption Edge ◽

Perovskite Structure ◽

Surface Defect ◽

Defect Density ◽

Optical Absorption Edge ◽

Surface Defect Density

LaTiO2N NP synthesized from flame made LaTiO3 NP exhibits less absorption background above the optical absorption edge than that synthesized from flame made La2Ti2O7 NP, suggesting a low surface defect density.

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Enhancement of photoelectrochemical performance in ferroelectric films via the introduction of an Au buffer layer

Journal of Semiconductors ◽

10.1088/1674-4926/42/11/112701 ◽

2021 ◽

Vol 42 (11) ◽

pp. 112701

Author(s):

Dawei Cao ◽

Ming Li ◽

Jianfei Zhu ◽

Yanfang He ◽

Tong Chen ◽

...

Keyword(s):

Electric Field ◽

Buffer Layer ◽

Water Splitting ◽

Charge Separation ◽

Sol Gel ◽

Ferroelectric Films ◽

Photoelectrochemical Performance ◽

Band Bending ◽

Polarization Electric Field ◽

Pec Water Splitting

Abstract The inefficient separation of photogenerated carriers has become a serious problem that limits the photoelectrochemical (PEC) performance of semiconductors. Herein, a sol-gel method was used to prepare BiFeO3 ferroelectric thin films with FTO and FTO/Au as substrates, respectively. The polarization electric field of the ferroelectric can more effectively separate the carriers generated in the photoelectrode. Meanwhile, the introduction of an Au buffer layer can reduce the resistance in the process of charge transfer, accelerate the carrier migration, and enhance the efficiency of the charge separation. Under light irradiation, Au/BiFeO3 photoelectrode exhibited an extraordinary improvement in PEC water splitting compared with BiFeO3. In addition, the ferroelectric polarization electric field causes band bending, which further accelerates the separation of electrons and holes and improves the PEC performance of the photoelectrode. This work promotes the effective application of ferroelectric films in PEC water splitting.

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