Hydrothermal Cobalt Doping of Titanium Dioxide Nanotubes towards Photoanode Activity Enhancement
Abstract
:1. Introduction
2. Materials and Methods
2.1. Apparatus
2.2. Chemicals
3. Results
3.1. Preparation of the Electrode Materials
3.2. Morphology and Composition of the Samples
Scanning Electron Microscope and Energy Dispersive X-Ray Analysis
3.3. Structure
3.3.1. X-Ray Powder Diffraction
3.3.2. Raman Spectroscopy
3.3.3. X-ray Photoelectron Spectroscopy
3.4. Reflectance UV-Vis Spectroscopy
3.5. Electrochemical and Photoelectrochemical Properties
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Sample | D101 (nm) | D112 (nm) | D200 (nm) | D211 (nm) |
---|---|---|---|---|
TiO2-NTs | 18.2 | 28.2 | 16.5 | 25.5 |
Co-TiO2-NTs | 15.3 | 41.1 | 14.6 | 17.5 |
Co-TiO2 | 19.7 | 34.6 | 15.0 | 13.3 |
Sample | Efb (V) for 1 Hz | Efb (V) for 100 Hz | Efb (V) for 1000 Hz |
---|---|---|---|
TiO2-NTs | −0.21 ± 0.02 | −0.22 ± 0.02 | −0.25 ± 0.02 |
Co-TiO2-NTs | −0.02 ± 0.02 | 0.00 ± 0.02 | 0.00 ± 0.02 |
Co-TiO2 | 0.15 ± 0.02 | 0.06 ± 0.02 | 0.02 ± 0.02 |
Sample | Δj (μA·cm−2) | jl/jd | Δj/P (μA∙W−1) |
---|---|---|---|
TiO2-NTs | 12.51 | 33.08 | 12.5 |
Co-TiO2-NTs | 32.71 | 137.29 | 32.7 |
Co-TiO2 | 11.68 | 33.44 | 11.7 |
Electrode Material | Luminous Intensity (mW·cm2) | Energy Bandgap, Eg (eV) | Photocurrent Density (μA·cm 2)/E * (V) | Enhancement Factor (jdoped/jTiO2) | Ref. |
---|---|---|---|---|---|
TiO2-NTs | 100 | 2.99 | 12.9 at 0.5 V | 1 | This work |
Co-TiO2 | 2.85 | 12.0 at 0.5 V | 0.9 | ||
Co-TiO2-NTs | 2.92 | 33.3 at 0.5 V | 2.6 | ||
Co-TiO2-NTs | 100 | 3.09 | 95.0 at 0.5 V | 1.5 | [68] |
Co-TiO2-NTs | 100 | no data | 40.0 at 0.4 V | 3.0 | [67] |
Cr-TiO2-NTs | 100 | 2.82 | 360.0 at 1.0 V | 9.2 | [64] |
B-TiO2-NTs | 100 | 2.91 | 311.0 at 0.5 V | 7.4 | [69] |
V-TiO2-NTs | 16 | no data | 5.8 at 0.5 V | 4.8 | [70] |
Ag-TiO2 film | 4.4 | 2.5 | 1.2 at 0.2 V | 3.5 | [71] |
Fe-TiO2 nanorods | 100 | 3.12 | 550.0 at 0 V | 5.5 | [65] |
Cu-TiO2 film | 44.42 | 2.82 | 18.2 at 0.4 V | 1.3 | [66] |
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Wtulich, M.; Szkoda, M.; Gajowiec, G.; Gazda, M.; Jurak, K.; Sawczak, M.; Lisowska-Oleksiak, A. Hydrothermal Cobalt Doping of Titanium Dioxide Nanotubes towards Photoanode Activity Enhancement. Materials 2021, 14, 1507. https://doi.org/10.3390/ma14061507
Wtulich M, Szkoda M, Gajowiec G, Gazda M, Jurak K, Sawczak M, Lisowska-Oleksiak A. Hydrothermal Cobalt Doping of Titanium Dioxide Nanotubes towards Photoanode Activity Enhancement. Materials. 2021; 14(6):1507. https://doi.org/10.3390/ma14061507
Chicago/Turabian StyleWtulich, Mariusz, Mariusz Szkoda, Grzegorz Gajowiec, Maria Gazda, Kacper Jurak, Mirosław Sawczak, and Anna Lisowska-Oleksiak. 2021. "Hydrothermal Cobalt Doping of Titanium Dioxide Nanotubes towards Photoanode Activity Enhancement" Materials 14, no. 6: 1507. https://doi.org/10.3390/ma14061507