Hydrogen as a probe for defects in materials: Isotherms and related microstructures of palladium-hydrogen thin films

Stefan Wagner; Astrid Pundt; Stefan Wagner; Astrid Pundt

doi:10.3934/matersci.2020.4.399

AIMS Materials Science

2020, Volume 7, Issue 4: 399-419. doi: 10.3934/matersci.2020.4.399

Previous Article Next Article

Research article Topical Sections

Hydrogen as a probe for defects in materials: Isotherms and related microstructures of palladium-hydrogen thin films

Stefan Wagner ^,,
Astrid Pundt

Karlsruhe Institute of Technology (KIT), Institute of Applied Materials (IAM-WK), Engelbert-Arnold-Straße 4, 76131 Karlsruhe, Germany

Received: 02 March 2020 Accepted: 26 May 2020 Published: 24 June 2020

Metal-hydrogen systems offer grand opportunities for studies on fundamental aspects of alloy thermodynamics. Palladium-hydrogen (Pd-H) thin films of nano crystalline, multi-oriented and epitaxial microstructures, electrolytically charged with hydrogen, serve as model systems. In these films thermodynamics of hydrogen absorption is modified by interface effects related to mechanical stress and to microstructural defects. Since in this respect hydrogen can be utilized to reveal the microstructural constituents of the films, we aim to investigate the distribution of sites (DOS) hydrogen occupies in the films’ solid solution regime. A σDOS model is proposed, taking the measured substrate-induced stress contribution to the chemical potential into account. This enables the determination of the different sites’ volume fractions and of pure site energy distributions by fitting measured isotherms. Interstitial sites, grain/domain boundary sites and deep traps are distinguished. Dislocations and vacancies are shown to have a minor impact on the films’ trapping of hydrogen atoms, while deep traps are related to the films’ surface. Enhanced binding energies in nano crystalline films can be ascribed to the tensile strain effect of grain boundaries acting on the grains. Measured surface trapping energies fit to the respective bulk values, while the trapping of hydrogen in grain/domain boundaries of the films is significantly increased. This can be interpreted with different grain/domain boundary structures. Different from octahedral interstitial site occupation, tetrahedral site occupation is suggested for grain/domain boundaries of the films.
- hydrogen,
- palladium,
- thin film,
- density of states,
- site occupancy,
- grain boundary,
- stress
Citation: Stefan Wagner, Astrid Pundt. Hydrogen as a probe for defects in materials: Isotherms and related microstructures of palladium-hydrogen thin films[J]. AIMS Materials Science, 2020, 7(4): 399-419. doi: 10.3934/matersci.2020.4.399

Related Papers:

Abstract

Metal-hydrogen systems offer grand opportunities for studies on fundamental aspects of alloy thermodynamics. Palladium-hydrogen (Pd-H) thin films of nano crystalline, multi-oriented and epitaxial microstructures, electrolytically charged with hydrogen, serve as model systems. In these films thermodynamics of hydrogen absorption is modified by interface effects related to mechanical stress and to microstructural defects. Since in this respect hydrogen can be utilized to reveal the microstructural constituents of the films, we aim to investigate the distribution of sites (DOS) hydrogen occupies in the films’ solid solution regime. A σDOS model is proposed, taking the measured substrate-induced stress contribution to the chemical potential into account. This enables the determination of the different sites’ volume fractions and of pure site energy distributions by fitting measured isotherms. Interstitial sites, grain/domain boundary sites and deep traps are distinguished. Dislocations and vacancies are shown to have a minor impact on the films’ trapping of hydrogen atoms, while deep traps are related to the films’ surface. Enhanced binding energies in nano crystalline films can be ascribed to the tensile strain effect of grain boundaries acting on the grains. Measured surface trapping energies fit to the respective bulk values, while the trapping of hydrogen in grain/domain boundaries of the films is significantly increased. This can be interpreted with different grain/domain boundary structures. Different from octahedral interstitial site occupation, tetrahedral site occupation is suggested for grain/domain boundaries of the films.

References

[1]	Peisl H (1978) Lattice strains due to hydrogen in metals, In: Alefeld G, Völkl J, Hydrogen in Metals I-Basic Properties, Heidelberg: Springer-Verlag.
[2]	Kirchheim R, Pundt A (2015) Hydrogen in Metals, In: Laughlin D, Hono K, Physical Metallurgy, 5 Eds., Elsevier, 2597-2705.
[3]	Fukai Y (2005) The Metal-Hydrogen System: Basic Bulk Properties, Heidelberg: Springer-Verlag.
[4]	Mooij L, Perkisas T, Palsson G, et al. (2014) The effect of microstructure on the hydrogenation of Mg/Fe thin film multilayers. Int J Hydrogen Energ 39:17092-17103. doi: 10.1016/j.ijhydene.2014.08.035
[5]	Hjörvarsson B, Andersson G, Karlsson E (1997) Metallic superlattices: Quasi two-dimensional playground for hydrogen. J Alloy Compd 253:51-57.
[6]	Pundt A, Kirchheim R (2006) Hydrogen in metals: microstructural aspects. Annu Rev Mater Res 36: 555-608. doi: 10.1146/annurev.matsci.36.090804.094451
[7]	Gremaud R, Gonzales-Silveira M, Pivak Y, et al. (2009) Hydrogenography of PdHx thin films: Influence of H-induced stress relaxation processes. Acta Mater 57:1209-1219. doi: 10.1016/j.actamat.2008.11.016
[8]	Baldi A, Gonzales-Silveira M, Palmisano V, et al. (2009) Destabilization of the Mg-H system through elastic constraints. Phys Rev Lett 102: 226102. doi: 10.1103/PhysRevLett.102.226102
[9]	Griessen R, Strohfeldt N, Giessen H (2016) Thermodynamics of the hybrid interaction of hydrogen with palladium nanoparticles. Nat Mater 15: 311-317. doi: 10.1038/nmat4480
[10]	Wagner S, Pundt A (2016) Quasi-thermodynamic model on hydride formation in palladium-hydrogen thin films: Impact of elastic and microstructural constraints. Int J Hydrogen Energ 41: 2727-2738. doi: 10.1016/j.ijhydene.2015.11.063
[11]	Schwarz R, Khachaturyan A (2006) Thermodynamics of open two-phase systems with coherent interfaces: Application to metal-hydrogen systems. Acta Mater 54: 313-323. doi: 10.1016/j.actamat.2005.08.044
[12]	Boes N, Züchner H (1976) Electrochemical methods for studying diffusion permeation and solubility of hydrogen in metals. J Less Common Met 49: 223-240. doi: 10.1016/0022-5088(76)90037-0
[13]	Züchner H, Rauf T (1991) Electrochemical isotherm measurements on the Pd-H and PdAg-H systems. J Less Common Met 172-174: 816-823. doi: 10.1016/0022-5088(91)90208-L
[14]	Samwer K, Johnson W (1983) Structure of glassy early-transition-late-transition-metal hydrides. Phys Rev B 28: 2907-2913. doi: 10.1103/PhysRevB.28.2907
[15]	Myers S, Baskes M, Birnbaum H, et al. (1992) Hydrogen interaction with defects in crystalline solids. Rev Mod Phys 64: 559-617. doi: 10.1103/RevModPhys.64.559
[16]	Baldi A, Narayan T, Koh A, et al. (2014) In situ detection of hydrogen induced phase transitions in individual palladium nanocrystals. Nat Mater 13: 1143-1148. doi: 10.1038/nmat4086
[17]	Iwaoka H, Arita M, Horita Z (2016) Hydrogen diffusion in ultrafine-grained palladium: Roles of dislocations and grain boundaries. Acta Mater 107: 168-177. doi: 10.1016/j.actamat.2016.01.069
[18]	Melikhova O, Cizek, J, Prochazka I (2014) Hydrogen induced defects in palladium. Acta Phys Pol A 125: 752-755. doi: 10.12693/APhysPolA.125.752
[19]	Wagner S, Klose P, Burlaka V, et al. (2019) Structural phase transitions in niobium hydrogen thin films: Mechanical stress, phase equilibria and critical temperatures. ChemPhysChem 20: 1890-1904. doi: 10.1002/cphc.201900247
[20]	Mooji L, Dam B (2013) Hysteresis and the role of nucleation and growth in the hydrogenation of Mg nanolayers. Phys Chem Chem Phys 15: 2782-2792. doi: 10.1039/c3cp44441d
[21]	Uchida H, Wagner S, Hamm M, et al. (2015) Absorption kinetics and hydride formation in magnesium films: Effect of driving force revisited. Acta Mater 85: 279-289. doi: 10.1016/j.actamat.2014.11.031
[22]	Mütschele T, Kirchheim R (1987) Segregation and diffusion of hydrogen in grain boundaries of palladium. Scripta Metall 21: 135-140. doi: 10.1016/0036-9748(87)90423-6
[23]	Weissmüller J, Lemier C (1999) Lattice constants of solid solution microstructures: The case of nanocrystalline Pd-H. Phys Rev Lett 82: 213-216. doi: 10.1103/PhysRevLett.82.213
[24]	Song G, Geitz M, Abromeit A, et al. (1996) Solubility isotherms of hydrogen in epitaxial Nb(110) films. Phys Rev B 54:14093-14101. doi: 10.1103/PhysRevB.54.14093
[25]	Hamm M, Burlaka V, Wagner S, et al. (2015) Achieving reversibility of ultra-high mechanical stress by hydrogen loading of thin films. Appl Phys Lett 106: 243108. doi: 10.1063/1.4922285
[26]	Laudahn U, Pundt A, Bicker M, et al. (1999) Hydrogen-induced stress in Nb single layers. J Alloy Compd 293-295: 490-494. doi: 10.1016/S0925-8388(99)00471-5
[27]	Wicke E, Brodowsky H (1978) Hydrogen in palladium and palladium alloys, In: Alefeld G, Völkl J, Hydrogen in Metals II, Berlin, Heidelberg: Springer-Verlag.
[28]	Lacher J (1937) A theoretical formula for the solubility of hydrogen in palladium. P Roy Soc Lond A-Mat 161: 525-545. doi: 10.1098/rspa.1937.0160
[29]	Olsson S, Blixt A, Hjörvarsson B (2005) Mean-field-like structural phase transition of H in Fe/V(001) superlattices. J Phys-Condens Mat 17: 2073-2084. doi: 10.1088/0953-8984/17/13/007
[30]	Papaconstantopoulos D, Klein B, Economou E, et al. (1978) Band structure and superconductivity of PdD_x and PdH_x. Phys Rev B 17: 141-150.
[31]	Kirchheim R (1988) Hydrogen solubility and diffusivity in defective and amorphous metals. Prog Mater Sci 32: 261-325. doi: 10.1016/0079-6425(88)90010-2
[32]	Züttel A (1988) Metall-hydride. Vorlesungsskript.
[33]	Larché F, Cahn J (1973) A linear theory of thermochemical equilibrium of solids under stress. Acta Metall 21: 1051-1063. doi: 10.1016/0001-6160(73)90021-7
[34]	Larché F, Cahn J (1985) The interactions of composition and stress in crystalline solids. Acta Metall 33: 331-357. doi: 10.1016/0001-6160(85)90077-X
[35]	Wagner S, Moser M, Greubel C, et al. (2013) Hydrogen microscopy-Hydrogen distribution in buckled niobium hydrogen thin films. Int J Hydrogen Energ 38: 13822-13830. doi: 10.1016/j.ijhydene.2013.08.006
[36]	Ohring M (1992) The materials science of thin films, San Diego: Academic Press.
[37]	Kirchheim R (1981) Interaction of hydrogen with dislocations in palladium-II. Interpretation of activity results by a Fermi-Dirac distribution. Acta Metall 29: 845-853.
[38]	Bankmann J, Pundt A, Kirchheim R (2003) Hydrogen loading behaviour of multi-component amorphous alloys: model and experiment. J Alloy Compd 356: 566-569.
[39]	White C, Stein D (1978) Sulfur segregation to grain boundaries in Ni₃Al and Ni₃(Al, Ti) alloys. Metall Trans A 9: 13-22. doi: 10.1007/BF02647165
[40]	Wagner S, Pundt A (2011) Combined impact of micro-structure and mechanical stress on the electrical resistivity of PdH_c thin films. Acta Mater 59: 1862-1870. doi: 10.1016/j.actamat.2010.11.052
[41]	Wagner S, Kramer T, Uchida U, et al. (2016) Mechanical stress and stress release channels in 10-350 nm palladium hydrogen thin films with different micro-structures. Acta Mater 114: 116-125. doi: 10.1016/j.actamat.2016.05.023
[42]	Kirchheim R, Mütschele T, Kieninger W (1988) Hydrogen in amorphous and nanocrystalline metals. Mater Sci Eng 99: 457-462. doi: 10.1016/0025-5416(88)90377-1
[43]	Pundt A, Nikitin E, Pekarski P, et al. (2004) Adhesion energy between metal films and polymers obtained by studying buckling induced by hydrogen. Acta Mater 52: 1579-1587. doi: 10.1016/j.actamat.2003.12.003
[44]	Lemier C, Weissmüller J (2007) Grain boundary segregation, stress and stretch: effects on hydrogen absorption in nanocrystalline palladium. Acta Mater 55: 1241-1254. doi: 10.1016/j.actamat.2006.09.030
[45]	Tan L, Allen T, Busby J (2013) Grain boundary engineering for structure materials of nuclear reactors. J Nucl Mat 441: 661-666. doi: 10.1016/j.jnucmat.2013.03.050
[46]	Chan S (1994) Degenerate epitaxy, coincidence epitaxy and origin of "special" boundaries in thin films. J Phys Chem Solids 55: 1137-1145. doi: 10.1016/0022-3697(94)90131-7
[47]	Brons J, Thompson G (2013) A comparison of grain boundary evolution during grain growth in fcc metals. Acta Mater 61:3936-3944. doi: 10.1016/j.actamat.2013.02.057
[48]	Divakar R, Raghunathan V (2003) Characterisation of interfaces in nanocrystalline palladium. Sadhana 28: 47-62. doi: 10.1007/BF02717125
[49]	Löffler J, Weissmüller J (1995) Grain-boundary atomic structure in nanocrystalline palladium from x-ray atomic distribution functions. Phys Rev B 52: 7076-7093. doi: 10.1103/PhysRevB.52.7076
[50]	Haas V, Birringer R, Gleiter H (1998) Preparation and characterisation of compacts from nanostructured powder produced in an aerosol flow condenser. Mater Sci Eng A-Struct 246: 86-92. doi: 10.1016/S0921-5093(97)00754-5
[51]	Gemma R (2011) Hydrogen in V-Fe thin films and Fe/V-Fe multi-layered thin films [Dissertation]. Göttingen: University of Gottingen.
[52]	Keblinski P, Wolf D, Phillpot S, et al. (1999) Structure of grain boundaries in nanocrystalline palladium by molecular dynamics simulation. Scripta Mater 41: 631-636. doi: 10.1016/S1359-6462(99)00142-6
[53]	Ferrin P, Kandoi S, Nilekar A, et al. (2012) Hydrogen adsorption, absorption and diffusion on and in transition metal surfaces: A DFT study. Surf Sci 606: 679-689. doi: 10.1016/j.susc.2011.12.017
[54]	Dong W, Ledentu V, Sautet Ph, et al. (1998) Hydrogen adsorption on palladium: a comparative theoretical study of different surfaces. Surf Sci 411: 123-136. doi: 10.1016/S0039-6028(98)00354-9
[55]	Conrad H, Ertl G, Latta E (1974) Adsorption of hydrogen on palladium single crystal surfaces. Surf Sci 41: 435-446. doi: 10.1016/0039-6028(74)90060-0
[56]	Vekilova O, Bazhanov D, Simak S, et al. (2009) First-principles study of vacancy-hydrogen interaction in Pd. Phys Rev B 80: 024101.
[57]	Cizek J, Melikhova O, Vlcek M, et al. (2014) Hydrogen interaction with defects in nanocrystalline, polycrystalline and epitaxial Pd films. J Nano Res 26: 123-133.
[58]	Wagner S (2014) Dünne palladium-wassersoff-schichten als modellsystem [Dissertation]. Göttingen: University of Göttingen.
[59]	Switendick A (1979) Band structure calculations for metal hydrogen systems. Z Phys Chem 117: 89-112. doi: 10.1524/zpch.1979.117.117.089
[60]	Weissmüller J, Lemier C (2000) On the size dependence of the critical point of nanoscale interstitial solid solutions. Phil Mag Lett 80: 411-418.

matersci-07-04-399-s001.pdf

Reader Comments

Your name:*

Email:*
© 2020 the Author(s), licensee AIMS Press. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0)