Multilayer crystal-amorphous Pd-based nanosheets on Si/SiO2 with interface-controlled ion transport for efficient hydrogen storage


Sarac B., Ivanov Y. P. , Karazehir T., Muehlbacher M., Sarac A. S. , Greer A. L. , ...More

INTERNATIONAL JOURNAL OF HYDROGEN ENERGY, vol.47, no.10, pp.6777-6788, 2022 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 47 Issue: 10
  • Publication Date: 2022
  • Doi Number: 10.1016/j.ijhydene.2021.12.040
  • Title of Journal : INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
  • Page Numbers: pp.6777-6788
  • Keywords: Hydrogen storage, Metallic glass, Palladium-silicon, Multilayer, Electrochemistry, HRSTEM, PALLADIUM THIN-FILMS, ADSORPTION, ABSORPTION, ALLOY, ELECTRODES, MICROSTRUCTURE, DIFFUSION, BEHAVIOR, HYDRIDE

Abstract

This contribution shows an unusually high hydrogen storage of multilayer amorphous (A) crystalline (C) Pd-Si based nanosheets when stacked in the right order. Samples with A/C/ A/C/A stacking sequence exhibit 40 and 12 times larger hydrogen sorption than monolithic crystalline and amorphous samples, respectively. The maximum capacitance calculated from the fitting of electrochemical impedance measurements of the same sample is twice larger than that of the conventional polycrystalline Pd films of similar thickness. Five times higher diffusion coefficient calculated from modified Cottrell equation is obtained compared to specimens with C/A/C/A/C stacking. For the A/C/A/C/A multilayers, nano bubbles with diameters of 1-2 nm are homogeneously distributed at Si/SiO2 interface, and PdHx crystal formation in these regions confirms hydrogen-metal interactions. Furthermore, corrosion-resistant amorphous top layer permits larger amounts of hydrogen ion transfer to inner layers. Thus, hydrogen storage and production can be enhanced by smart design of multilayers targeted for proton exchange membrane electrolysis or fuel cells. (c) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.