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Chemical and electronic structure analysis of a SrTiO3 (001)/p-Ge (001) hydrogen evolution photocathode

  • Kelsey A. Stoerzinger (a1), Yingge Du (a1), Steven R. Spurgeon (a2), Le Wang (a1), Demie Kepaptsoglou (a3) (a4) (a5), Quentin M. Ramasse (a3) (a6) (a7), Ethan J. Crumlin (a8) and Scott A. Chambers (a1)...

Germanium is a small-gap semiconductor that efficiently absorbs visible light, resulting in photoexcited electrons predicted to be sufficiently energetic to reduce H2O for H2 gas evolution. In order to protect the surface from corrosion and prevent surface charge recombination in contact with aqueous pH 7 electrolyte, we grew epitaxial SrTiO3 layers of different thicknesses on p-Ge (001) surfaces. Four-nanometer SrTiO3 allows photogenerated electrons to reach the surface and evolve H2 gas, while 13 nm SrTiO3 blocks these electrons. Ambient pressure x-ray photoelectron spectroscopy indicates that the surface readily dissociates H2O to form OH species, which may impact surface band bending.

Corresponding author
Address all correspondence to Kelsey A. Stoerzinger and Scott A. Chambers at;
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1.Cook, T.R., Dogutan, D.K., Reece, S.Y., Surendranath, Y., Teets, T.S., and Nocera, D.G.: Solar energy supply and storage for the legacy and nonlegacy worlds. Chem. Rev. 110, 64746502 (2010).
2.Walter, M.G., Warren, E.L., McKone, J.R., Boettcher, S.W., Mi, Q., Santori, E.A., and Lewis, N.S.: Solar water splitting cells. Chem. Rev. 110, 64466473 (2010).
3.Kudo, A. and Miseki, Y.: Heterogeneous photocatalyst materials for water splitting. Chem. Soc. Rev. 38, 253278 (2009).
4.Li, J. and Wu, N.: Semiconductor-based photocatalysts and photoelectrochemical cells for solar fuel generation: a review. Catal. Sci. Technol. 5, 13601384 (2015).
5.Alexander, B.D., Kulesza, P.J., Rutkowska, I., Solarska, R., and Augustynski, J.: Metal oxide photoanodes for solar hydrogen production. J. Mater. Chem. 18, 22982303 (2008).
6.Sivula, K. and van de Krol, R.: Semiconducting materials for photoelectrochemical energy conversion. Nat. Rev. Mater. 1, 15010 (2016).
7.Smith, W.A., Sharp, I.D., Strandwitz, N.C., and Bisquert, J.: Interfacial band-edge energetics for solar fuels production. Energy Environ. Sci. 8, 28512862 (2015).
8.Sze, S.M.: Physics of semiconductor devices (John Wiley and Sons Hoboken, 1981).
9.Prince, M.B.: Drift mobilities in semiconductors. I. Germanium. Phys. Rev. 92, 681687 (1953).
10.Chen, S. and Wang, L.-W.: Thermodynamic oxidation and reduction potentials of photocatalytic semiconductors in aqueous solution. Chem. Mater. 24, 36593666 (2012).
11.Erdélyi, V.R. and Green, M.: Hydrogen overpotential on germanium electrodes. Nature 182, 1592 (1958).
12.Memming, R. and Neumann, G.: Electrochemical reduction and hydrogen evolution on germanium electrodes. J. Electroanal. Chem. Interfacial Electrochem. 21, 295305 (1969).
13.Hu, S., Lewis, N.S., Ager, J.W., Yang, J., McKone, J.R., and Strandwitz, N.C.: Thin-film materials for the protection of semiconducting photoelectrodes in solar-fuel generators. J. Phys. Chem. C 119, 2420124228 (2015).
14.Kornblum, L., Fenning, D.P., Faucher, J., Hwang, J., Boni, A., Han, M.G., Morales-Acosta, M.D., Zhu, Y., Altman, E.I., Lee, M.L., Ahn, C.H., Walker, F.J., and Shao-Horn, Y.: Solar hydrogen production using epitaxial SrTiO3 on a GaAs photovoltaic. Energy Environ. Sci. 10, 377382 (2017).
15.Hudait, M.K., Clavel, M., Zhu, Y., Goley, P.S., Kundu, S., Maurya, D., and Priya, S.: Integration of SrTiO3 on crystallographically oriented epitaxial germanium for low-power device applications. ACS Appl. Mater. Interfaces 7, 54715479 (2015).
16.McDaniel, M.D., Ngo, T.Q., Posadas, A., Hu, C., Lu, S., Smith, D.J., Yu, E.T., Demkov, A.A., and Ekerdt, J.G.: A chemical route to monolithic integration of crystalline oxides on semiconductors. Adv. Mater. Interfaces 1, 1400081 (2014).
17.Chambers, S.A., Du, Y., Comes, R.B., Spurgeon, S.R., and Sushko, P.V.: The effects of core-level broadening in determining band alignment at the epitaxial SrTiO3(001)/p-Ge(001) heterojunction. Appl. Phys. Lett. 110, 082104 (2017).
18.Stoerzinger, K.A., Hong, W.T., Crumlin, E.J., Bluhm, H., and Shao-Horn, Y.: Insights into electrochemical reactions from ambient pressure photoelectron spectroscopy. Acc. Chem. Res. 48, 29762983 (2015).
19.Ponath, P., Posadas, A.B., Hatch, R.C., and Demkov, A.A.: Preparation of a clean Ge(001) surface using oxygen plasma cleaning. J. Vac. Sci. Technol. B: Nanotechnol. Microelectron.: Mater. Process. Meas. Phenom. 31, 031201 (2013).
20.Jahangir-Moghadam, M., Ahmadi-Majlan, K., Shen, X., Droubay, T., Bowden, M., Chrysler, M., Su, D., Chambers, S.A., and Ngai, J.H.: Band-gap engineering at a semiconductor–crystalline oxide interface. Adv. Mater. Interfaces 2, 1400497 (2015).
21.Jones, L., Yang, H., Pennycook, T.J., Marshall, M.S.J., Van Aert, S., Browning, N.D., Castell, M.R., and Nellist, P.D.: Smart align—a new tool for robust non-rigid registration of scanning microscope data. Adv. Struct. Chem. Imaging 1, 8 (2015).
22.Krivanek, O.L., Chisholm, M.F., Nicolosi, V., Pennycook, T.J., Corbin, G.J., Dellby, N., Murfitt, M.F., Own, C.S., Szilagyi, Z.S., Oxley, M.P., Pantelides, S.T., and Pennycook, S.J.: Atom-by-atom structural and chemical analysis by annular dark-field electron microscopy. Nature 464, 571 (2010).
23.Grass, M.E., Karlsson, P.G., Aksoy, F., Lundqvist, M., Wannberg, B., Mun, B.S., Hussain, Z., and Liu, Z.: New ambient pressure photoemission endstation at advanced light source beamline 9.3.2. Rev. Sci. Instrum. 81, 053106 (2010).
24.Stoerzinger, K.A., Hong, W.T., Crumlin, E.J., Bluhm, H., Biegalski, M.D., and Shao-Horn, Y.: Water reactivity on the LaCoO3 (001) surface: an ambient pressure x-ray photoelectron spectroscopy study. J. Phys. Chem. C 118, 1973319741 (2014).
25.Jones, L., Varambhia, A., Beanland, R., Kepaptsoglou, D., Griffiths, I., Ishizuka, A., Azough, F., Freer, R., Ishizuka, K., Cherns, D., Ramasse, Q.M., Lozano-Perez, S., and Nellist, P.D.: Managing dose-, damage- and data-rates in multi-frame spectrum-imaging. Microscopy (In press), DOI: 10.1093/jmicro/dfx125 (2018).
26.Ping, Y., Sundararaman, R., and Goddard, W.A. III: Solvation effects on the band edge positions of photocatalysts from first principles. Phys. Chem. Chem. Phys. 17, 3049930509 (2015).
27.Castelli, I.E., Thygesen, K.S., and Jacobsen, K.W.: Calculated Pourbaix diagrams of cubic perovskites for water splitting: stability against corrosion. Top. Catal. 57, 265272 (2014).
28.Quan, L.N., Jang, Y.H., Stoerzinger, K.A., May, K.J., Jang, Y.J., Kochuveedu, S.T., Shao-Horn, Y., and Kim, D.H.: Soft-template-carbonization route to highly textured mesoporous carbon-tio2 inverse opals for efficient photocatalytic and photoelectrochemical applications. Phys. Chem. Chem. Phys. 16, 90239030 (2014).
29.Kwon, K.C., Choi, S., Hong, K., Andoshe, D.M., Suh, J.M., Kim, C., Choi, K.S., Oh, J.H., Kim, S.Y., and Jang, H.W.: Tungsten disulfide thin film/p-type Si heterojunction photocathode for efficient photochemical hydrogen production. MRS Commun. 7, 272279 (2017).
30.Thorne, J.E., Zhao, Y., He, D., Fan, S., Vanka, S., Mi, Z., and Wang, D.: Understanding the role of co-catalysts on silicon photocathodes using intensity modulated photocurrent spectroscopy. Phys. Chem. Chem. Phys. 19, 2965329659 (2017).
31.Esposito, D.V., Levin, I., Moffat, T.P., and Talin, A.A.: H2 evolution at Si-based metal–insulator–semiconductor photoelectrodes enhanced by inversion channel charge collection and H spillover. Nat. Mater. 12, 562 (2013).
32.Stoerzinger, K.A., Comes, R., Spurgeon, S.R., Thevuthasan, S., Ihm, K., Crumlin, E.J., and Chambers, S.A.: Influence of LaFeO3 surface termination on water reactivity. J. Phys. Chem. Lett. 8, 10381043 (2017).
33.Favaro, M., Abdi, F.F., Lamers, M., Crumlin, E.J., Liu, Z., van de Krol, R., and Starr, D.E.: Light-induced surface reactions at the bismuth vanadate/potassium phosphate interface. J. Phys. Chem. B 122, 801809 (2018).
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MRS Communications
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Supplementary materials

Stoerzinger et al. supplementary material
Figures S1-S10 and Table S1

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