Corresponding Author

De-sheng KONG(kongdscn@eyou.com)


Surface recombination of the photogenerated electron-hole pairs at semiconductor/electrolyte interface is one of the most essential reasons responsible for lowering photoconversion efficiency (Φ) of light to chemical energy for photoelectrochemical (PEC) water splitting reaction. In this paper,the catalytic effect of sodium carbonate on the oxygen evolution reaction (OER) over TiO2 nanotubes photoanode during PEC water splitting was investigated by performing photocurrent and ac impedance measurements. It was demonstrated that the addiction of 1 mmol•L-1 Na2CO3 in 0.5 mol•L-1 NaClO4 electrolyte can effectively improve the charge transfer properties for the photogenerated holes across TiO2/electrolyte interface and inhibit the recombination of photogenerated carriers at this interface. As a result,both the measured photocurrent was increased and the photoconversion efficiency was enhanced.

Graphical Abstract


photogenerated holes, surface recombination, photocurrent, anodic oxygen evolution, Mott-Schottky analysis

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[1] Bockris J O?M. The origin of ideas on a Hydrogen Economy and its solution to the decay of the environment[J]. International Journal of Hydrogen Energy, 2002, 27(7/8): 731-740.

[2] Guo L J, Zhao L, Jing D W, et al. Solar hydrogen production and its development in China[J]. Energy, 2009, 34(9): 1073-1090.

[3] Zhang X D(张学迪), Wang J(王静), Zhao X(赵曦), et al. Solar-hydrogen production by photoelectrochemical water splitting using TiO2 nanotube-based photoanodes[C]// The 16th National Conference on Electrochemistry, October 13-17, 2011, Chong Qing University, Chongqing, China. 2011: F-053.

[4] Kitano M, Tsujimaru K, Anpo M. Hydrogen production using highly active titanium oxide-based photocatalysts[J]. Topics in Catalysis, 2008, 49: 4-17.

[5] Harrison K, Levene J I. Chapter 3. Electrolysis of water[M]// Rajeshwar K, McConnell R, Licht S, Edt. Solar hydrogen generation: Toward a renewable energy future. New York: Springer, 2008.

[6] Fujishima A, Honda K. Electrochemical photolysis of water at a semiconductor electrode[J]. Nature, 1972, 238: 37-38.

[7] Chen X, Shen S, Guo L J, et al. Semiconductor-based photocatalytic hydrogen generation[J]. Chemical Reviews, 2010, 110(11): 6503-6570.

[8] Murphy A B, Barnes P R F, Randeniya L K, et al. Efficiency of solarwater splitting using semiconductor electrodes[J]. International Journal of Hydrogen Energy, 2006, 31: 1999-2017.

[9] Van de Krol R, Schoonman J. Chapter 6. Photo-electrochemical production of hydrogen[M]// Hanjali? K, Krol R van de, Leki? A, Edt. Sustainable energy technologies: Options and prospects. Dordrecht: Springer, 2008.

[10] Peter L M, Li J, Peat R. Surface recombination at semiconductor electrodes: Part I. Transient and steady-state photocurrents[J]. Journal of Electroanalytical Chemistry, 1984, 165(1/2): 29-40.

[11] Li J, Peat R, Peter L M. Surface recombination at semiconductor electrodes: Part II. Photoinduced “near-surface” recombination centres in p-GaP[J]. Journal of Electroanalytical Chemistry, 1984, 165(1/2): 41-59.

[12] Cowan A J, Tang J, Leng W, et al. Water splitting by nanocrystalline TiO2 in a complete photoelectrochemical cell exhibits efficiencies limited by charge recombination[J]. The Journal of Physical Chemistry C, 2010, 114(9): 4208-4214.

[13] Sayama K, Arakawa H. Significant effect of carbonate addition on stoichiometric photodecomposition of liquid water into hydrogen and oxygen from platinum-titanium(IV) oxide suspension[J]. Journal of the Chemical Society, Chemical Communications, 1992, (2): 150-152.

[14] Sayama K, Arakawa H. Effect of carbonate salt addition on the photocatalytic decomposition of liquid water over Pt-TiO2 catalyst[J]. Journal of the Chemical Society, Faraday Transactions, 1997, 93 (8): 1647-1654.

[15] Arakawa H, Sayama K. Solar hydrogen production: Significant effect of Na2CO3 addition on water splitting using simple oxide semiconductor photocatalysts[J]. Catalysis Surveys from Japan, 2000, 4: 75-80.

[16] Zhu J, Z?ch M. Nanostructured materials for photocatalytic hydrogen production[J]. Current Opinion in Colloid & Interface Science, 2009, 14: 260-269.

[17] Grimes C A, Mor G K. TiO2 Nanotube arrays: Synthesis, properties, and applications[M]. New York: Springer Science + Business Media, 2009: Chapter 1.

[18] Kong D S, Chen S H, Wang C, et al. A study of the passive films on Cr by capacitance measurement[J]. Corrosion Science, 2003, 45 (4): 747-758.

[19] Milczarek G, Kasuya A, Mamykin S, et al. Optimization of a two-compartment photoelectrochemical cell for solar hydrogen production[J]. International Journal of Hydrogen Energy, 2003, 28: 919-926.

[20] Shiga A, Tsujiko A, Yae S, et al. High photocurrent quantum yields in short wavelengths for nanocrystalline anatase-type TiO2 film electrodes compared with those for rutile-type[J]. Bulletin of the Chemical Society of Japan, 1998, 71(9): 2119-2125.

[21] Shaban Y A, Khan S U M. Surface grooved visible light active carbon modified (CM)-n-TiO2 thin films for efficient photoelectrochemical splitting of water[J]. Chemical Physics, 2007, 339: 73-85.

[22] Prter L M. Dynamic aspects of semiconductor photoelectrochemistry[J]. Chemical Reviews, 1990, 90 (5): 753-769.

[23] a) G?rtner W W. Depletion-layer photoeffects in semiconductors[J]. Physical Review, 1959, 116(1): 84-87; b) Butler M A. Photoelectrolysis and physical properties of the semiconducting electrode WO3[J]. Journal of Applied Physics, 1977, 48(5): 1914-1920.

[24] Kong D S, Wu J X. An electrochemical study on the anodic oxygen evolution on oxide film covered titanium[J]. Journal of The Electrochemical Society, 2008, 155(1): C32-C40.

[25] Kong D S. Anion-incorporation model (AIM) for interpreting the interfacial physical origin of the faradaic pseudo-capacitance observed on anodized valve metals—with anodized titanium in fluoride-containing perchloric acid as an example[J]. Langmuir, 2010, 26(7): 4880-4891.

[26] Kong D S (孔德生), Liu H Y (刘海燕), Lv W H (吕文华), et al. Electrochemical studies on the ionic charge transfer properties of the cxygen vacancy defects in the oxide films formed on titanium[J]. Journal of Electrochemistry (电化学), 2009, 15(3): 320-325.

[27] Morrison S R. Electrochemistry at semiconductor and oxidized metal electrodes[M]. Wu H H (吴辉煌), Trs. Beijing: Science Press (科学出版社), 1988: Chpter 2, Chapter 4.

[28] Nakato Y, Tsumura A, Tsumura H. The concept of “sueface-trapped hole” as an intermediate of anodic reaction of a gallium phosphide semiconductor electrode[J]. Chemistry Letters, 1981, 127-130.



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