Nanoporous Pd-Cu-Si Amorphous Thin Films for Electrochemical Hydrogen Storage and Sensing

Research output: Contribution to journalArticleResearchpeer-review

Authors

  • Baran Sarac
  • Tolga Karazehir
  • Eray Yüce
  • Marlene Mühlbacher
  • A. Sezai Sarac

External Organisational units

  • Erich Schmid Institute of Materials Science
  • Department of Energy System Engineering
  • Polymer Science and Technology

Abstract

Increasing the efficiency of hydrogen storage and release using recent generation metallic glass nanofilms (MGNFs) offers green solutions for nanoscale energy applications. Contrary to flat nanofilms, enhanced electrochemical performance of Pd–Cu–Si MGNF assemblies for hydrogen interaction is obtained on different sizes and configurations of a nanoporous alumina support. In particular, 10 nm thick samples with pore diameters of 25 nm reach a high specific pseudocapacitance per unit mass of 637 F g–1, which is more than an order of magnitude larger than for flat samples, surpassing the precious metal-based systems in the literature. The same electrode exhibits the highest double-layer capacitance calculated from the equivalent circuit model of the electrochemical impedance spectra, featuring its eligibility for hydrogen nanosensors. A rough and fully coated surface is attained for samples of 250 μm thickness and above, while smoother and open-pore structures are observed for lower thicknesses, inducing a capillary pressure and turbulent flow effect for the latter case. The comparison of cyclic voltammetry (CV) profiles recorded in the region where hydrogen–metal interactions occur confirms a remarkable desorption charge difference, reaching 2.5 times higher values for the 50 nm thick 25 nm pore diameter than the 40 nm pore diameter and flat electrodes, and lower absolute impedance values near-DC range revealing their highly conductive behavior.

Details

Original languageEnglish
Pages (from-to)2672-2680
Number of pages9
JournalACS Applied Energy Materials
Volume4.2021
Issue number3
DOIs
Publication statusPublished - 18 Feb 2021