Exploiting defects in TiO₂ inverse opal for enhanced photoelectrochemical water splitting

S. K. Karuturi, R. Yew, P. R. Narangari, J. Wong-Leung, L. Li, K. Vora, H. H. Tan, and C. Jagadish, “CdS / TiO2 photoanodes via solution ion transfer method for highly efficient solar hydrogen generation,” Nano Futures 2(1), 015004 (2018).
[Crossref]

S. Kashiwaya, J. Morasch, V. Streibel, T. Toupance, W. Jaegermann, and A. Klein, “The work function of TiO2,” Surfaces 1(1), 73–89 (2018).
[Crossref]

J.-W. Yun, K. Y. Ryu, T. K. Nguyen, F. Ullah, Y. Chang Park, and Y. S. Kim, “Tuning optical band gap by electrochemical reduction in TiO2 nanorods for improving photocatalytic activities,” RSC Advances 7(11), 6202–6208 (2017).
[Crossref]

T. Jafari, E. Moharreri, A. S. Amin, R. Miao, W. Song, and S. L. Suib, “Photocatalytic water splitting - the untamed dream: a review of recent advances,” Molecules 21(7), 900 (2016).
[Crossref] [PubMed]

A. P. Singh, N. Kodan, B. R. Mehta, A. Dey, and S. Krishnamurthy, “In-situ plasma hydrogenated TiO2 thin films for enhanced photoelectrochemical properties,” Mater. Res. Bull. 76, 284–291 (2016).
[Crossref]

L. Han, Z. Ma, Z. Luo, G. Liu, J. Ma, and X. An, “Enhanced visible light and photocatalytic performance of TiO2 nanotubes by hydrogenation at lower temperature,” RSC Advances 6(8), 6643–6650 (2016).
[Crossref]

M. Mehta, N. Kodan, S. Kumar, A. Kaushal, L. Mayrhofer, M. Walter, M. Moseler, A. Dey, S. Krishnamurthy, S. Basu, and A. P. Singh, “Hydrogen treated anatase TiO2: a new experimental approach and further insights from theory,” J. Mater. Chem. A Mater. Energy Sustain. 4(7), 2670–2681 (2016).
[Crossref]

D. K. Behara, A. K. Ummireddi, V. Aragonda, P. K. Gupta, R. G. Pala, and S. Sivakumar, “Coupled optical absorption, charge carrier separation, and surface electrochemistry in surface disordered/hydrogenated TiO2 for enhanced PEC water splitting reaction,” Phys. Chem. Chem. Phys. 18(12), 8364–8377 (2016).
[Crossref] [PubMed]

K. Du, G. Liu, M. Li, C. Wu, X. Chen, and K. Wang, “Electrochemical reduction and capacitance of hybrid titanium dioxides - nanotube arrays and nanograss,” Electrochim. Acta 210, 367–374 (2016).
[Crossref]

P. Yan, G. Liu, C. Ding, H. Han, J. Shi, Y. Gan, and C. Li, “Photoelectrochemical water splitting promoted with a disordered surface layer created by electrochemical reduction,” ACS Appl. Mater. Interfaces 7(6), 3791–3796 (2015).
[Crossref] [PubMed]

Z. Zhang, M. N. Hedhili, H. Zhu, and P. Wang, “Electrochemical reduction induced self-doping of Ti3+ for efficient water splitting performance on TiO2 based photoelectrodes,” Phys. Chem. Chem. Phys. 15(37), 15637–15644 (2013).
[Crossref] [PubMed]

R. C. Rai, “Analysis of the Urbach tails in absorption spectra of undoped ZnO thin films,” J. Appl. Phys. 113(15), 153508 (2013).
[Crossref]

T. Gu, “Role of oxygen vacancies in TiO2-based resistive switches,” J. Appl. Phys. 113(3), 033707 (2013).
[Crossref]

Y. Yamada and Y. Kanemitsu, “Determination of electron and hole lifetimes of rutile and anatase TiO2 single crystals,” Appl. Phys. Lett. 101(13), 133907 (2012).
[Crossref]

H. M. Chen, C. K. Chen, R. S. Liu, L. Zhang, J. Zhang, and D. P. Wilkinson, “Nano-architecture and material designs for water splitting photoelectrodes,” Chem. Soc. Rev. 41(17), 5654–5671 (2012).
[Crossref] [PubMed]

S. K. Karuturi, C. Cheng, L. Liu, L. Tat Su, H. J. Fan, and A. I. Y. Tok, “Inverse opals coupled with nanowires as photoelectrochemical anode,” Nano Energy 1(2), 322–327 (2012).
[Crossref]

S. K. Karuturi, J. Luo, C. Cheng, L. Liu, L. T. Su, A. I. Y. Tok, and H. J. Fan, “A novel photoanode with three-dimensionally, hierarchically ordered nanobushes for highly efficient photoelectrochemical cells,” Adv. Mater. 24(30), 4157–4162 (2012).
[Crossref] [PubMed]

C. Cheng, S. K. Karuturi, L. Liu, J. Liu, H. Li, L. T. Su, A. I. Y. Tok, and H. J. Fan, “Quantum-dot-sensitized TiO2 inverse opals for photoelectrochemical hydrogen generation,” Small 8(1), 37–42 (2012).
[Crossref] [PubMed]

F. Tian, Y. Zhang, J. Zhang, and C. Pan, “Raman spectroscopy : a new approach to measure the percentage of anatase TiO2 exposed (001) facets,” J. Phys. Chem. C 116(13), 7515–7519 (2012).
[Crossref]

M. Kong, Y. Li, X. Chen, T. Tian, P. Fang, F. Zheng, and X. Zhao, “Tuning the relative concentration ratio of bulk defects to surface defects in TiO2 nanocrystals leads to high photocatalytic efficiency,” J. Am. Chem. Soc. 133(41), 16414–16417 (2011).
[Crossref] [PubMed]

X. Chen, L. Liu, P. Y. Yu, and S. S. Mao, “Increasing solar absorption for photocatalysis with black hydrogenated titanium dioxide nanocrystals,” Science 331(6018), 746–750 (2011).
[Crossref] [PubMed]

M. G. Walter, E. L. Warren, J. R. McKone, S. W. Boettcher, Q. Mi, E. A. Santori, and N. S. Lewis, “Solar water splitting cells,” Chem. Rev. 110(11), 6446–6473 (2010).
[Crossref] [PubMed]

M. C. Biesinger, L. W. Lau, A. R. Gerson, and R. S. Smart, “Resolving surface chemical states in XPS analysis of first row transition metals, oxides and hydroxides: Sc, Ti, V, Cu and Zn,” Appl. Surf. Sci. 257(3), 887–898 (2010).
[Crossref]

A. C. Papageorgiou, N. S. Beglitis, C. L. Pang, G. Teobaldi, G. Cabailh, Q. Chen, A. J. Fisher, W. A. Hofer, and G. Thornton, “Electron traps and their effect on the surface chemistry of TiO2(110),” Proc. Natl. Acad. Sci. U.S.A. 107(6), 2391–2396 (2010).
[Crossref] [PubMed]

A. Janotti, J. B. Varley, P. Rinke, N. Umezawa, G. Kresse, and C. G. Van de Walle, “Hybrid functional studies of the oxygen vacancy in TiO2,” Phys. Rev. B Condens. Matter Mater. Phys. 81(8), 085212 (2010).
[Crossref]

S. Sahoo, A. K. Arora, and V. Sridharan, “Raman line shapes of optical phonons of different symmetries in anatase TiO2 nanocrystals,” J. Phys. Chem. C 113(39), 16927–16933 (2009).
[Crossref]

R. van de Krol, Y. Liang, and J. Schoonman, “Solar hydrogen production with nanostructured metal oxides,” J. Mater. Chem. 18(20), 2311–2320 (2008).
[Crossref]

M. A. Henderson, W. S. Epling, C. H. F. Peden, and C. L. Perkins, “Insights into photoexcited electron scavenging processes on TiO2 obtained from studies of the reaction of O2 with OH groups adsorbed at electronic defects on TiO2 (110),” J. Phys. Chem. B 107(2), 534–545 (2003).
[Crossref]

I. Justicia, P. Ordejón, G. Canto, J. L. Mozos, J. Fraxedas, G. A. Battiston, R. Gerbasi, and A. Figueras, “Designed self-doped titanium dioxide thin films for efficient visible-light photocatalysis,” Adv. Mater. 14(19), 1399–1402 (2002).
[Crossref]

M. Grätzel, “Photoelectrochemical cells,” Nature 414(6861), 338–344 (2001).
[Crossref] [PubMed]

D. Bersani, P. P. Lottici, and X. Ding, “Phonon confinement effects in the Raman scattering by TiO2 nanocrystals phonon confinement effects in the Raman scattering by TiO2 nanocrystals,” Appl. Phys. Lett. 73(1), 72–75 (1998).

J. C. Parker and R. W. Siegel, “Raman microprobe study of nanophase TiO2 and oxidation-induced spectral changes,” J. Mater. Res. 5(6), 1246–1252 (1990).
[Crossref]

D. Tafalla and P. Salvador, “Kinetic approach to the photocurrent transients in water photoelectrolysis at n-TiO2 electrodes,” J. Electrochem. Soc. 137(6), 1810–1815 (1990).
[Crossref]

C. Sanchez, K. D. Sieber, and G. A. Somorjai, “The photoelectrochemistry of niobium doped α-Fe2O3,” J. Electroanal. Chem. 252(2), 269–290 (1988).
[Crossref]

C. M. Greenlief, J. M. White, C. S. Ko, and R. J. Gorte, “An XPS investigation of titanium dioxide thin films on polycrystalline platinum,” J. Phys. Chem. 89(23), 5025–5028 (1985).
[Crossref]

S. E. Lindquist, B. Finnström, and L. Tegner, “Photoelectrochemical properties of polycrystalline TiO2 thin film electrodes on quartz substrates,” J. Electrochem. Soc. 130(2), 351–358 (1983).
[Crossref]

T. Ohsaka, F. Izumi, and Y. Fujiki, “Raman spectrum of anatase TiO2,” J. Raman Spectrosc. 7(6), 321–324 (1978).
[Crossref]

A. Fujishima and K. Honda, “Electrochemical photolysis of water at a semiconductor electrode,” Nature 238(5358), 37–38 (1972).
[Crossref] [PubMed]

T. Jafari, E. Moharreri, A. S. Amin, R. Miao, W. Song, and S. L. Suib, “Photocatalytic water splitting - the untamed dream: a review of recent advances,” Molecules 21(7), 900 (2016).
[Crossref] [PubMed]

L. Han, Z. Ma, Z. Luo, G. Liu, J. Ma, and X. An, “Enhanced visible light and photocatalytic performance of TiO2 nanotubes by hydrogenation at lower temperature,” RSC Advances 6(8), 6643–6650 (2016).
[Crossref]

D. K. Behara, A. K. Ummireddi, V. Aragonda, P. K. Gupta, R. G. Pala, and S. Sivakumar, “Coupled optical absorption, charge carrier separation, and surface electrochemistry in surface disordered/hydrogenated TiO2 for enhanced PEC water splitting reaction,” Phys. Chem. Chem. Phys. 18(12), 8364–8377 (2016).
[Crossref] [PubMed]

S. Sahoo, A. K. Arora, and V. Sridharan, “Raman line shapes of optical phonons of different symmetries in anatase TiO2 nanocrystals,” J. Phys. Chem. C 113(39), 16927–16933 (2009).
[Crossref]

M. Mehta, N. Kodan, S. Kumar, A. Kaushal, L. Mayrhofer, M. Walter, M. Moseler, A. Dey, S. Krishnamurthy, S. Basu, and A. P. Singh, “Hydrogen treated anatase TiO2: a new experimental approach and further insights from theory,” J. Mater. Chem. A Mater. Energy Sustain. 4(7), 2670–2681 (2016).
[Crossref]

I. Justicia, P. Ordejón, G. Canto, J. L. Mozos, J. Fraxedas, G. A. Battiston, R. Gerbasi, and A. Figueras, “Designed self-doped titanium dioxide thin films for efficient visible-light photocatalysis,” Adv. Mater. 14(19), 1399–1402 (2002).
[Crossref]

A. C. Papageorgiou, N. S. Beglitis, C. L. Pang, G. Teobaldi, G. Cabailh, Q. Chen, A. J. Fisher, W. A. Hofer, and G. Thornton, “Electron traps and their effect on the surface chemistry of TiO2(110),” Proc. Natl. Acad. Sci. U.S.A. 107(6), 2391–2396 (2010).
[Crossref] [PubMed]

D. K. Behara, A. K. Ummireddi, V. Aragonda, P. K. Gupta, R. G. Pala, and S. Sivakumar, “Coupled optical absorption, charge carrier separation, and surface electrochemistry in surface disordered/hydrogenated TiO2 for enhanced PEC water splitting reaction,” Phys. Chem. Chem. Phys. 18(12), 8364–8377 (2016).
[Crossref] [PubMed]

D. Bersani, P. P. Lottici, and X. Ding, “Phonon confinement effects in the Raman scattering by TiO2 nanocrystals phonon confinement effects in the Raman scattering by TiO2 nanocrystals,” Appl. Phys. Lett. 73(1), 72–75 (1998).

M. C. Biesinger, L. W. Lau, A. R. Gerson, and R. S. Smart, “Resolving surface chemical states in XPS analysis of first row transition metals, oxides and hydroxides: Sc, Ti, V, Cu and Zn,” Appl. Surf. Sci. 257(3), 887–898 (2010).
[Crossref]

M. G. Walter, E. L. Warren, J. R. McKone, S. W. Boettcher, Q. Mi, E. A. Santori, and N. S. Lewis, “Solar water splitting cells,” Chem. Rev. 110(11), 6446–6473 (2010).
[Crossref] [PubMed]

A. C. Papageorgiou, N. S. Beglitis, C. L. Pang, G. Teobaldi, G. Cabailh, Q. Chen, A. J. Fisher, W. A. Hofer, and G. Thornton, “Electron traps and their effect on the surface chemistry of TiO2(110),” Proc. Natl. Acad. Sci. U.S.A. 107(6), 2391–2396 (2010).
[Crossref] [PubMed]

I. Justicia, P. Ordejón, G. Canto, J. L. Mozos, J. Fraxedas, G. A. Battiston, R. Gerbasi, and A. Figueras, “Designed self-doped titanium dioxide thin films for efficient visible-light photocatalysis,” Adv. Mater. 14(19), 1399–1402 (2002).
[Crossref]

J.-W. Yun, K. Y. Ryu, T. K. Nguyen, F. Ullah, Y. Chang Park, and Y. S. Kim, “Tuning optical band gap by electrochemical reduction in TiO2 nanorods for improving photocatalytic activities,” RSC Advances 7(11), 6202–6208 (2017).
[Crossref]

H. M. Chen, C. K. Chen, R. S. Liu, L. Zhang, J. Zhang, and D. P. Wilkinson, “Nano-architecture and material designs for water splitting photoelectrodes,” Chem. Soc. Rev. 41(17), 5654–5671 (2012).
[Crossref] [PubMed]

H. M. Chen, C. K. Chen, R. S. Liu, L. Zhang, J. Zhang, and D. P. Wilkinson, “Nano-architecture and material designs for water splitting photoelectrodes,” Chem. Soc. Rev. 41(17), 5654–5671 (2012).
[Crossref] [PubMed]

A. C. Papageorgiou, N. S. Beglitis, C. L. Pang, G. Teobaldi, G. Cabailh, Q. Chen, A. J. Fisher, W. A. Hofer, and G. Thornton, “Electron traps and their effect on the surface chemistry of TiO2(110),” Proc. Natl. Acad. Sci. U.S.A. 107(6), 2391–2396 (2010).
[Crossref] [PubMed]

K. Du, G. Liu, M. Li, C. Wu, X. Chen, and K. Wang, “Electrochemical reduction and capacitance of hybrid titanium dioxides - nanotube arrays and nanograss,” Electrochim. Acta 210, 367–374 (2016).
[Crossref]

M. Kong, Y. Li, X. Chen, T. Tian, P. Fang, F. Zheng, and X. Zhao, “Tuning the relative concentration ratio of bulk defects to surface defects in TiO2 nanocrystals leads to high photocatalytic efficiency,” J. Am. Chem. Soc. 133(41), 16414–16417 (2011).
[Crossref] [PubMed]

X. Chen, L. Liu, P. Y. Yu, and S. S. Mao, “Increasing solar absorption for photocatalysis with black hydrogenated titanium dioxide nanocrystals,” Science 331(6018), 746–750 (2011).
[Crossref] [PubMed]

S. K. Karuturi, C. Cheng, L. Liu, L. Tat Su, H. J. Fan, and A. I. Y. Tok, “Inverse opals coupled with nanowires as photoelectrochemical anode,” Nano Energy 1(2), 322–327 (2012).
[Crossref]

S. K. Karuturi, J. Luo, C. Cheng, L. Liu, L. T. Su, A. I. Y. Tok, and H. J. Fan, “A novel photoanode with three-dimensionally, hierarchically ordered nanobushes for highly efficient photoelectrochemical cells,” Adv. Mater. 24(30), 4157–4162 (2012).
[Crossref] [PubMed]

C. Cheng, S. K. Karuturi, L. Liu, J. Liu, H. Li, L. T. Su, A. I. Y. Tok, and H. J. Fan, “Quantum-dot-sensitized TiO2 inverse opals for photoelectrochemical hydrogen generation,” Small 8(1), 37–42 (2012).
[Crossref] [PubMed]

A. P. Singh, N. Kodan, B. R. Mehta, A. Dey, and S. Krishnamurthy, “In-situ plasma hydrogenated TiO2 thin films for enhanced photoelectrochemical properties,” Mater. Res. Bull. 76, 284–291 (2016).
[Crossref]

M. Mehta, N. Kodan, S. Kumar, A. Kaushal, L. Mayrhofer, M. Walter, M. Moseler, A. Dey, S. Krishnamurthy, S. Basu, and A. P. Singh, “Hydrogen treated anatase TiO2: a new experimental approach and further insights from theory,” J. Mater. Chem. A Mater. Energy Sustain. 4(7), 2670–2681 (2016).
[Crossref]

P. Yan, G. Liu, C. Ding, H. Han, J. Shi, Y. Gan, and C. Li, “Photoelectrochemical water splitting promoted with a disordered surface layer created by electrochemical reduction,” ACS Appl. Mater. Interfaces 7(6), 3791–3796 (2015).
[Crossref] [PubMed]

D. Bersani, P. P. Lottici, and X. Ding, “Phonon confinement effects in the Raman scattering by TiO2 nanocrystals phonon confinement effects in the Raman scattering by TiO2 nanocrystals,” Appl. Phys. Lett. 73(1), 72–75 (1998).

K. Du, G. Liu, M. Li, C. Wu, X. Chen, and K. Wang, “Electrochemical reduction and capacitance of hybrid titanium dioxides - nanotube arrays and nanograss,” Electrochim. Acta 210, 367–374 (2016).
[Crossref]

M. A. Henderson, W. S. Epling, C. H. F. Peden, and C. L. Perkins, “Insights into photoexcited electron scavenging processes on TiO2 obtained from studies of the reaction of O2 with OH groups adsorbed at electronic defects on TiO2 (110),” J. Phys. Chem. B 107(2), 534–545 (2003).
[Crossref]

S. K. Karuturi, J. Luo, C. Cheng, L. Liu, L. T. Su, A. I. Y. Tok, and H. J. Fan, “A novel photoanode with three-dimensionally, hierarchically ordered nanobushes for highly efficient photoelectrochemical cells,” Adv. Mater. 24(30), 4157–4162 (2012).
[Crossref] [PubMed]

C. Cheng, S. K. Karuturi, L. Liu, J. Liu, H. Li, L. T. Su, A. I. Y. Tok, and H. J. Fan, “Quantum-dot-sensitized TiO2 inverse opals for photoelectrochemical hydrogen generation,” Small 8(1), 37–42 (2012).
[Crossref] [PubMed]

S. K. Karuturi, C. Cheng, L. Liu, L. Tat Su, H. J. Fan, and A. I. Y. Tok, “Inverse opals coupled with nanowires as photoelectrochemical anode,” Nano Energy 1(2), 322–327 (2012).
[Crossref]

M. Kong, Y. Li, X. Chen, T. Tian, P. Fang, F. Zheng, and X. Zhao, “Tuning the relative concentration ratio of bulk defects to surface defects in TiO2 nanocrystals leads to high photocatalytic efficiency,” J. Am. Chem. Soc. 133(41), 16414–16417 (2011).
[Crossref] [PubMed]

I. Justicia, P. Ordejón, G. Canto, J. L. Mozos, J. Fraxedas, G. A. Battiston, R. Gerbasi, and A. Figueras, “Designed self-doped titanium dioxide thin films for efficient visible-light photocatalysis,” Adv. Mater. 14(19), 1399–1402 (2002).
[Crossref]

S. E. Lindquist, B. Finnström, and L. Tegner, “Photoelectrochemical properties of polycrystalline TiO2 thin film electrodes on quartz substrates,” J. Electrochem. Soc. 130(2), 351–358 (1983).
[Crossref]

A. C. Papageorgiou, N. S. Beglitis, C. L. Pang, G. Teobaldi, G. Cabailh, Q. Chen, A. J. Fisher, W. A. Hofer, and G. Thornton, “Electron traps and their effect on the surface chemistry of TiO2(110),” Proc. Natl. Acad. Sci. U.S.A. 107(6), 2391–2396 (2010).
[Crossref] [PubMed]

I. Justicia, P. Ordejón, G. Canto, J. L. Mozos, J. Fraxedas, G. A. Battiston, R. Gerbasi, and A. Figueras, “Designed self-doped titanium dioxide thin films for efficient visible-light photocatalysis,” Adv. Mater. 14(19), 1399–1402 (2002).
[Crossref]

T. Ohsaka, F. Izumi, and Y. Fujiki, “Raman spectrum of anatase TiO2,” J. Raman Spectrosc. 7(6), 321–324 (1978).
[Crossref]

A. Fujishima and K. Honda, “Electrochemical photolysis of water at a semiconductor electrode,” Nature 238(5358), 37–38 (1972).
[Crossref] [PubMed]

P. Yan, G. Liu, C. Ding, H. Han, J. Shi, Y. Gan, and C. Li, “Photoelectrochemical water splitting promoted with a disordered surface layer created by electrochemical reduction,” ACS Appl. Mater. Interfaces 7(6), 3791–3796 (2015).
[Crossref] [PubMed]

I. Justicia, P. Ordejón, G. Canto, J. L. Mozos, J. Fraxedas, G. A. Battiston, R. Gerbasi, and A. Figueras, “Designed self-doped titanium dioxide thin films for efficient visible-light photocatalysis,” Adv. Mater. 14(19), 1399–1402 (2002).
[Crossref]

M. C. Biesinger, L. W. Lau, A. R. Gerson, and R. S. Smart, “Resolving surface chemical states in XPS analysis of first row transition metals, oxides and hydroxides: Sc, Ti, V, Cu and Zn,” Appl. Surf. Sci. 257(3), 887–898 (2010).
[Crossref]

C. M. Greenlief, J. M. White, C. S. Ko, and R. J. Gorte, “An XPS investigation of titanium dioxide thin films on polycrystalline platinum,” J. Phys. Chem. 89(23), 5025–5028 (1985).
[Crossref]

M. Grätzel, “Photoelectrochemical cells,” Nature 414(6861), 338–344 (2001).
[Crossref] [PubMed]

C. M. Greenlief, J. M. White, C. S. Ko, and R. J. Gorte, “An XPS investigation of titanium dioxide thin films on polycrystalline platinum,” J. Phys. Chem. 89(23), 5025–5028 (1985).
[Crossref]

T. Gu, “Role of oxygen vacancies in TiO2-based resistive switches,” J. Appl. Phys. 113(3), 033707 (2013).
[Crossref]

D. K. Behara, A. K. Ummireddi, V. Aragonda, P. K. Gupta, R. G. Pala, and S. Sivakumar, “Coupled optical absorption, charge carrier separation, and surface electrochemistry in surface disordered/hydrogenated TiO2 for enhanced PEC water splitting reaction,” Phys. Chem. Chem. Phys. 18(12), 8364–8377 (2016).
[Crossref] [PubMed]

P. Yan, G. Liu, C. Ding, H. Han, J. Shi, Y. Gan, and C. Li, “Photoelectrochemical water splitting promoted with a disordered surface layer created by electrochemical reduction,” ACS Appl. Mater. Interfaces 7(6), 3791–3796 (2015).
[Crossref] [PubMed]

L. Han, Z. Ma, Z. Luo, G. Liu, J. Ma, and X. An, “Enhanced visible light and photocatalytic performance of TiO2 nanotubes by hydrogenation at lower temperature,” RSC Advances 6(8), 6643–6650 (2016).
[Crossref]

Z. Zhang, M. N. Hedhili, H. Zhu, and P. Wang, “Electrochemical reduction induced self-doping of Ti3+ for efficient water splitting performance on TiO2 based photoelectrodes,” Phys. Chem. Chem. Phys. 15(37), 15637–15644 (2013).
[Crossref] [PubMed]

M. A. Henderson, W. S. Epling, C. H. F. Peden, and C. L. Perkins, “Insights into photoexcited electron scavenging processes on TiO2 obtained from studies of the reaction of O2 with OH groups adsorbed at electronic defects on TiO2 (110),” J. Phys. Chem. B 107(2), 534–545 (2003).
[Crossref]

A. C. Papageorgiou, N. S. Beglitis, C. L. Pang, G. Teobaldi, G. Cabailh, Q. Chen, A. J. Fisher, W. A. Hofer, and G. Thornton, “Electron traps and their effect on the surface chemistry of TiO2(110),” Proc. Natl. Acad. Sci. U.S.A. 107(6), 2391–2396 (2010).
[Crossref] [PubMed]

A. Fujishima and K. Honda, “Electrochemical photolysis of water at a semiconductor electrode,” Nature 238(5358), 37–38 (1972).
[Crossref] [PubMed]

T. Ohsaka, F. Izumi, and Y. Fujiki, “Raman spectrum of anatase TiO2,” J. Raman Spectrosc. 7(6), 321–324 (1978).
[Crossref]

S. Kashiwaya, J. Morasch, V. Streibel, T. Toupance, W. Jaegermann, and A. Klein, “The work function of TiO2,” Surfaces 1(1), 73–89 (2018).
[Crossref]

T. Jafari, E. Moharreri, A. S. Amin, R. Miao, W. Song, and S. L. Suib, “Photocatalytic water splitting - the untamed dream: a review of recent advances,” Molecules 21(7), 900 (2016).
[Crossref] [PubMed]

S. K. Karuturi, R. Yew, P. R. Narangari, J. Wong-Leung, L. Li, K. Vora, H. H. Tan, and C. Jagadish, “CdS / TiO2 photoanodes via solution ion transfer method for highly efficient solar hydrogen generation,” Nano Futures 2(1), 015004 (2018).
[Crossref]

A. Janotti, J. B. Varley, P. Rinke, N. Umezawa, G. Kresse, and C. G. Van de Walle, “Hybrid functional studies of the oxygen vacancy in TiO2,” Phys. Rev. B Condens. Matter Mater. Phys. 81(8), 085212 (2010).
[Crossref]

I. Justicia, P. Ordejón, G. Canto, J. L. Mozos, J. Fraxedas, G. A. Battiston, R. Gerbasi, and A. Figueras, “Designed self-doped titanium dioxide thin films for efficient visible-light photocatalysis,” Adv. Mater. 14(19), 1399–1402 (2002).
[Crossref]

Y. Yamada and Y. Kanemitsu, “Determination of electron and hole lifetimes of rutile and anatase TiO2 single crystals,” Appl. Phys. Lett. 101(13), 133907 (2012).
[Crossref]

S. K. Karuturi, R. Yew, P. R. Narangari, J. Wong-Leung, L. Li, K. Vora, H. H. Tan, and C. Jagadish, “CdS / TiO2 photoanodes via solution ion transfer method for highly efficient solar hydrogen generation,” Nano Futures 2(1), 015004 (2018).
[Crossref]

C. Cheng, S. K. Karuturi, L. Liu, J. Liu, H. Li, L. T. Su, A. I. Y. Tok, and H. J. Fan, “Quantum-dot-sensitized TiO2 inverse opals for photoelectrochemical hydrogen generation,” Small 8(1), 37–42 (2012).
[Crossref] [PubMed]

S. K. Karuturi, J. Luo, C. Cheng, L. Liu, L. T. Su, A. I. Y. Tok, and H. J. Fan, “A novel photoanode with three-dimensionally, hierarchically ordered nanobushes for highly efficient photoelectrochemical cells,” Adv. Mater. 24(30), 4157–4162 (2012).
[Crossref] [PubMed]

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M. Mehta, N. Kodan, S. Kumar, A. Kaushal, L. Mayrhofer, M. Walter, M. Moseler, A. Dey, S. Krishnamurthy, S. Basu, and A. P. Singh, “Hydrogen treated anatase TiO2: a new experimental approach and further insights from theory,” J. Mater. Chem. A Mater. Energy Sustain. 4(7), 2670–2681 (2016).
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A. P. Singh, N. Kodan, B. R. Mehta, A. Dey, and S. Krishnamurthy, “In-situ plasma hydrogenated TiO2 thin films for enhanced photoelectrochemical properties,” Mater. Res. Bull. 76, 284–291 (2016).
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M. Mehta, N. Kodan, S. Kumar, A. Kaushal, L. Mayrhofer, M. Walter, M. Moseler, A. Dey, S. Krishnamurthy, S. Basu, and A. P. Singh, “Hydrogen treated anatase TiO2: a new experimental approach and further insights from theory,” J. Mater. Chem. A Mater. Energy Sustain. 4(7), 2670–2681 (2016).
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[Crossref] [PubMed]

C. Cheng, S. K. Karuturi, L. Liu, J. Liu, H. Li, L. T. Su, A. I. Y. Tok, and H. J. Fan, “Quantum-dot-sensitized TiO2 inverse opals for photoelectrochemical hydrogen generation,” Small 8(1), 37–42 (2012).
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S. K. Karuturi, R. Yew, P. R. Narangari, J. Wong-Leung, L. Li, K. Vora, H. H. Tan, and C. Jagadish, “CdS / TiO2 photoanodes via solution ion transfer method for highly efficient solar hydrogen generation,” Nano Futures 2(1), 015004 (2018).
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P. Yan, G. Liu, C. Ding, H. Han, J. Shi, Y. Gan, and C. Li, “Photoelectrochemical water splitting promoted with a disordered surface layer created by electrochemical reduction,” ACS Appl. Mater. Interfaces 7(6), 3791–3796 (2015).
[Crossref] [PubMed]

C. Cheng, S. K. Karuturi, L. Liu, J. Liu, H. Li, L. T. Su, A. I. Y. Tok, and H. J. Fan, “Quantum-dot-sensitized TiO2 inverse opals for photoelectrochemical hydrogen generation,” Small 8(1), 37–42 (2012).
[Crossref] [PubMed]

C. Cheng, S. K. Karuturi, L. Liu, J. Liu, H. Li, L. T. Su, A. I. Y. Tok, and H. J. Fan, “Quantum-dot-sensitized TiO2 inverse opals for photoelectrochemical hydrogen generation,” Small 8(1), 37–42 (2012).
[Crossref] [PubMed]

S. K. Karuturi, J. Luo, C. Cheng, L. Liu, L. T. Su, A. I. Y. Tok, and H. J. Fan, “A novel photoanode with three-dimensionally, hierarchically ordered nanobushes for highly efficient photoelectrochemical cells,” Adv. Mater. 24(30), 4157–4162 (2012).
[Crossref] [PubMed]

S. K. Karuturi, C. Cheng, L. Liu, L. Tat Su, H. J. Fan, and A. I. Y. Tok, “Inverse opals coupled with nanowires as photoelectrochemical anode,” Nano Energy 1(2), 322–327 (2012).
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S. K. Karuturi, J. Luo, C. Cheng, L. Liu, L. T. Su, A. I. Y. Tok, and H. J. Fan, “A novel photoanode with three-dimensionally, hierarchically ordered nanobushes for highly efficient photoelectrochemical cells,” Adv. Mater. 24(30), 4157–4162 (2012).
[Crossref] [PubMed]

L. Han, Z. Ma, Z. Luo, G. Liu, J. Ma, and X. An, “Enhanced visible light and photocatalytic performance of TiO2 nanotubes by hydrogenation at lower temperature,” RSC Advances 6(8), 6643–6650 (2016).
[Crossref]

L. Han, Z. Ma, Z. Luo, G. Liu, J. Ma, and X. An, “Enhanced visible light and photocatalytic performance of TiO2 nanotubes by hydrogenation at lower temperature,” RSC Advances 6(8), 6643–6650 (2016).
[Crossref]

L. Han, Z. Ma, Z. Luo, G. Liu, J. Ma, and X. An, “Enhanced visible light and photocatalytic performance of TiO2 nanotubes by hydrogenation at lower temperature,” RSC Advances 6(8), 6643–6650 (2016).
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X. Chen, L. Liu, P. Y. Yu, and S. S. Mao, “Increasing solar absorption for photocatalysis with black hydrogenated titanium dioxide nanocrystals,” Science 331(6018), 746–750 (2011).
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M. Mehta, N. Kodan, S. Kumar, A. Kaushal, L. Mayrhofer, M. Walter, M. Moseler, A. Dey, S. Krishnamurthy, S. Basu, and A. P. Singh, “Hydrogen treated anatase TiO2: a new experimental approach and further insights from theory,” J. Mater. Chem. A Mater. Energy Sustain. 4(7), 2670–2681 (2016).
[Crossref]

M. G. Walter, E. L. Warren, J. R. McKone, S. W. Boettcher, Q. Mi, E. A. Santori, and N. S. Lewis, “Solar water splitting cells,” Chem. Rev. 110(11), 6446–6473 (2010).
[Crossref] [PubMed]

A. P. Singh, N. Kodan, B. R. Mehta, A. Dey, and S. Krishnamurthy, “In-situ plasma hydrogenated TiO2 thin films for enhanced photoelectrochemical properties,” Mater. Res. Bull. 76, 284–291 (2016).
[Crossref]

M. Mehta, N. Kodan, S. Kumar, A. Kaushal, L. Mayrhofer, M. Walter, M. Moseler, A. Dey, S. Krishnamurthy, S. Basu, and A. P. Singh, “Hydrogen treated anatase TiO2: a new experimental approach and further insights from theory,” J. Mater. Chem. A Mater. Energy Sustain. 4(7), 2670–2681 (2016).
[Crossref]

M. G. Walter, E. L. Warren, J. R. McKone, S. W. Boettcher, Q. Mi, E. A. Santori, and N. S. Lewis, “Solar water splitting cells,” Chem. Rev. 110(11), 6446–6473 (2010).
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T. Jafari, E. Moharreri, A. S. Amin, R. Miao, W. Song, and S. L. Suib, “Photocatalytic water splitting - the untamed dream: a review of recent advances,” Molecules 21(7), 900 (2016).
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T. Jafari, E. Moharreri, A. S. Amin, R. Miao, W. Song, and S. L. Suib, “Photocatalytic water splitting - the untamed dream: a review of recent advances,” Molecules 21(7), 900 (2016).
[Crossref] [PubMed]

S. Kashiwaya, J. Morasch, V. Streibel, T. Toupance, W. Jaegermann, and A. Klein, “The work function of TiO2,” Surfaces 1(1), 73–89 (2018).
[Crossref]

M. Mehta, N. Kodan, S. Kumar, A. Kaushal, L. Mayrhofer, M. Walter, M. Moseler, A. Dey, S. Krishnamurthy, S. Basu, and A. P. Singh, “Hydrogen treated anatase TiO2: a new experimental approach and further insights from theory,” J. Mater. Chem. A Mater. Energy Sustain. 4(7), 2670–2681 (2016).
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S. K. Karuturi, R. Yew, P. R. Narangari, J. Wong-Leung, L. Li, K. Vora, H. H. Tan, and C. Jagadish, “CdS / TiO2 photoanodes via solution ion transfer method for highly efficient solar hydrogen generation,” Nano Futures 2(1), 015004 (2018).
[Crossref]

J.-W. Yun, K. Y. Ryu, T. K. Nguyen, F. Ullah, Y. Chang Park, and Y. S. Kim, “Tuning optical band gap by electrochemical reduction in TiO2 nanorods for improving photocatalytic activities,” RSC Advances 7(11), 6202–6208 (2017).
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D. K. Behara, A. K. Ummireddi, V. Aragonda, P. K. Gupta, R. G. Pala, and S. Sivakumar, “Coupled optical absorption, charge carrier separation, and surface electrochemistry in surface disordered/hydrogenated TiO2 for enhanced PEC water splitting reaction,” Phys. Chem. Chem. Phys. 18(12), 8364–8377 (2016).
[Crossref] [PubMed]

F. Tian, Y. Zhang, J. Zhang, and C. Pan, “Raman spectroscopy : a new approach to measure the percentage of anatase TiO2 exposed (001) facets,” J. Phys. Chem. C 116(13), 7515–7519 (2012).
[Crossref]

A. C. Papageorgiou, N. S. Beglitis, C. L. Pang, G. Teobaldi, G. Cabailh, Q. Chen, A. J. Fisher, W. A. Hofer, and G. Thornton, “Electron traps and their effect on the surface chemistry of TiO2(110),” Proc. Natl. Acad. Sci. U.S.A. 107(6), 2391–2396 (2010).
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A. C. Papageorgiou, N. S. Beglitis, C. L. Pang, G. Teobaldi, G. Cabailh, Q. Chen, A. J. Fisher, W. A. Hofer, and G. Thornton, “Electron traps and their effect on the surface chemistry of TiO2(110),” Proc. Natl. Acad. Sci. U.S.A. 107(6), 2391–2396 (2010).
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[Crossref]

J.-W. Yun, K. Y. Ryu, T. K. Nguyen, F. Ullah, Y. Chang Park, and Y. S. Kim, “Tuning optical band gap by electrochemical reduction in TiO2 nanorods for improving photocatalytic activities,” RSC Advances 7(11), 6202–6208 (2017).
[Crossref]

S. Sahoo, A. K. Arora, and V. Sridharan, “Raman line shapes of optical phonons of different symmetries in anatase TiO2 nanocrystals,” J. Phys. Chem. C 113(39), 16927–16933 (2009).
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D. Tafalla and P. Salvador, “Kinetic approach to the photocurrent transients in water photoelectrolysis at n-TiO2 electrodes,” J. Electrochem. Soc. 137(6), 1810–1815 (1990).
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C. Sanchez, K. D. Sieber, and G. A. Somorjai, “The photoelectrochemistry of niobium doped α-Fe2O3,” J. Electroanal. Chem. 252(2), 269–290 (1988).
[Crossref]

M. G. Walter, E. L. Warren, J. R. McKone, S. W. Boettcher, Q. Mi, E. A. Santori, and N. S. Lewis, “Solar water splitting cells,” Chem. Rev. 110(11), 6446–6473 (2010).
[Crossref] [PubMed]

R. van de Krol, Y. Liang, and J. Schoonman, “Solar hydrogen production with nanostructured metal oxides,” J. Mater. Chem. 18(20), 2311–2320 (2008).
[Crossref]

P. Yan, G. Liu, C. Ding, H. Han, J. Shi, Y. Gan, and C. Li, “Photoelectrochemical water splitting promoted with a disordered surface layer created by electrochemical reduction,” ACS Appl. Mater. Interfaces 7(6), 3791–3796 (2015).
[Crossref] [PubMed]

C. Sanchez, K. D. Sieber, and G. A. Somorjai, “The photoelectrochemistry of niobium doped α-Fe2O3,” J. Electroanal. Chem. 252(2), 269–290 (1988).
[Crossref]

J. C. Parker and R. W. Siegel, “Raman microprobe study of nanophase TiO2 and oxidation-induced spectral changes,” J. Mater. Res. 5(6), 1246–1252 (1990).
[Crossref]

M. Mehta, N. Kodan, S. Kumar, A. Kaushal, L. Mayrhofer, M. Walter, M. Moseler, A. Dey, S. Krishnamurthy, S. Basu, and A. P. Singh, “Hydrogen treated anatase TiO2: a new experimental approach and further insights from theory,” J. Mater. Chem. A Mater. Energy Sustain. 4(7), 2670–2681 (2016).
[Crossref]

A. P. Singh, N. Kodan, B. R. Mehta, A. Dey, and S. Krishnamurthy, “In-situ plasma hydrogenated TiO2 thin films for enhanced photoelectrochemical properties,” Mater. Res. Bull. 76, 284–291 (2016).
[Crossref]

D. K. Behara, A. K. Ummireddi, V. Aragonda, P. K. Gupta, R. G. Pala, and S. Sivakumar, “Coupled optical absorption, charge carrier separation, and surface electrochemistry in surface disordered/hydrogenated TiO2 for enhanced PEC water splitting reaction,” Phys. Chem. Chem. Phys. 18(12), 8364–8377 (2016).
[Crossref] [PubMed]

M. C. Biesinger, L. W. Lau, A. R. Gerson, and R. S. Smart, “Resolving surface chemical states in XPS analysis of first row transition metals, oxides and hydroxides: Sc, Ti, V, Cu and Zn,” Appl. Surf. Sci. 257(3), 887–898 (2010).
[Crossref]

C. Sanchez, K. D. Sieber, and G. A. Somorjai, “The photoelectrochemistry of niobium doped α-Fe2O3,” J. Electroanal. Chem. 252(2), 269–290 (1988).
[Crossref]

T. Jafari, E. Moharreri, A. S. Amin, R. Miao, W. Song, and S. L. Suib, “Photocatalytic water splitting - the untamed dream: a review of recent advances,” Molecules 21(7), 900 (2016).
[Crossref] [PubMed]

S. Sahoo, A. K. Arora, and V. Sridharan, “Raman line shapes of optical phonons of different symmetries in anatase TiO2 nanocrystals,” J. Phys. Chem. C 113(39), 16927–16933 (2009).
[Crossref]

S. Kashiwaya, J. Morasch, V. Streibel, T. Toupance, W. Jaegermann, and A. Klein, “The work function of TiO2,” Surfaces 1(1), 73–89 (2018).
[Crossref]

C. Cheng, S. K. Karuturi, L. Liu, J. Liu, H. Li, L. T. Su, A. I. Y. Tok, and H. J. Fan, “Quantum-dot-sensitized TiO2 inverse opals for photoelectrochemical hydrogen generation,” Small 8(1), 37–42 (2012).
[Crossref] [PubMed]

S. K. Karuturi, J. Luo, C. Cheng, L. Liu, L. T. Su, A. I. Y. Tok, and H. J. Fan, “A novel photoanode with three-dimensionally, hierarchically ordered nanobushes for highly efficient photoelectrochemical cells,” Adv. Mater. 24(30), 4157–4162 (2012).
[Crossref] [PubMed]

T. Jafari, E. Moharreri, A. S. Amin, R. Miao, W. Song, and S. L. Suib, “Photocatalytic water splitting - the untamed dream: a review of recent advances,” Molecules 21(7), 900 (2016).
[Crossref] [PubMed]

D. Tafalla and P. Salvador, “Kinetic approach to the photocurrent transients in water photoelectrolysis at n-TiO2 electrodes,” J. Electrochem. Soc. 137(6), 1810–1815 (1990).
[Crossref]

S. K. Karuturi, R. Yew, P. R. Narangari, J. Wong-Leung, L. Li, K. Vora, H. H. Tan, and C. Jagadish, “CdS / TiO2 photoanodes via solution ion transfer method for highly efficient solar hydrogen generation,” Nano Futures 2(1), 015004 (2018).
[Crossref]

S. K. Karuturi, C. Cheng, L. Liu, L. Tat Su, H. J. Fan, and A. I. Y. Tok, “Inverse opals coupled with nanowires as photoelectrochemical anode,” Nano Energy 1(2), 322–327 (2012).
[Crossref]

S. E. Lindquist, B. Finnström, and L. Tegner, “Photoelectrochemical properties of polycrystalline TiO2 thin film electrodes on quartz substrates,” J. Electrochem. Soc. 130(2), 351–358 (1983).
[Crossref]

A. C. Papageorgiou, N. S. Beglitis, C. L. Pang, G. Teobaldi, G. Cabailh, Q. Chen, A. J. Fisher, W. A. Hofer, and G. Thornton, “Electron traps and their effect on the surface chemistry of TiO2(110),” Proc. Natl. Acad. Sci. U.S.A. 107(6), 2391–2396 (2010).
[Crossref] [PubMed]

A. C. Papageorgiou, N. S. Beglitis, C. L. Pang, G. Teobaldi, G. Cabailh, Q. Chen, A. J. Fisher, W. A. Hofer, and G. Thornton, “Electron traps and their effect on the surface chemistry of TiO2(110),” Proc. Natl. Acad. Sci. U.S.A. 107(6), 2391–2396 (2010).
[Crossref] [PubMed]

F. Tian, Y. Zhang, J. Zhang, and C. Pan, “Raman spectroscopy : a new approach to measure the percentage of anatase TiO2 exposed (001) facets,” J. Phys. Chem. C 116(13), 7515–7519 (2012).
[Crossref]

M. Kong, Y. Li, X. Chen, T. Tian, P. Fang, F. Zheng, and X. Zhao, “Tuning the relative concentration ratio of bulk defects to surface defects in TiO2 nanocrystals leads to high photocatalytic efficiency,” J. Am. Chem. Soc. 133(41), 16414–16417 (2011).
[Crossref] [PubMed]

S. K. Karuturi, C. Cheng, L. Liu, L. Tat Su, H. J. Fan, and A. I. Y. Tok, “Inverse opals coupled with nanowires as photoelectrochemical anode,” Nano Energy 1(2), 322–327 (2012).
[Crossref]

S. K. Karuturi, J. Luo, C. Cheng, L. Liu, L. T. Su, A. I. Y. Tok, and H. J. Fan, “A novel photoanode with three-dimensionally, hierarchically ordered nanobushes for highly efficient photoelectrochemical cells,” Adv. Mater. 24(30), 4157–4162 (2012).
[Crossref] [PubMed]

C. Cheng, S. K. Karuturi, L. Liu, J. Liu, H. Li, L. T. Su, A. I. Y. Tok, and H. J. Fan, “Quantum-dot-sensitized TiO2 inverse opals for photoelectrochemical hydrogen generation,” Small 8(1), 37–42 (2012).
[Crossref] [PubMed]

S. Kashiwaya, J. Morasch, V. Streibel, T. Toupance, W. Jaegermann, and A. Klein, “The work function of TiO2,” Surfaces 1(1), 73–89 (2018).
[Crossref]

J.-W. Yun, K. Y. Ryu, T. K. Nguyen, F. Ullah, Y. Chang Park, and Y. S. Kim, “Tuning optical band gap by electrochemical reduction in TiO2 nanorods for improving photocatalytic activities,” RSC Advances 7(11), 6202–6208 (2017).
[Crossref]

A. Janotti, J. B. Varley, P. Rinke, N. Umezawa, G. Kresse, and C. G. Van de Walle, “Hybrid functional studies of the oxygen vacancy in TiO2,” Phys. Rev. B Condens. Matter Mater. Phys. 81(8), 085212 (2010).
[Crossref]

D. K. Behara, A. K. Ummireddi, V. Aragonda, P. K. Gupta, R. G. Pala, and S. Sivakumar, “Coupled optical absorption, charge carrier separation, and surface electrochemistry in surface disordered/hydrogenated TiO2 for enhanced PEC water splitting reaction,” Phys. Chem. Chem. Phys. 18(12), 8364–8377 (2016).
[Crossref] [PubMed]

R. van de Krol, Y. Liang, and J. Schoonman, “Solar hydrogen production with nanostructured metal oxides,” J. Mater. Chem. 18(20), 2311–2320 (2008).
[Crossref]

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