TY - JOUR

T1 - Nanoporous Pd-Cu-Si Amorphous Thin Films for Electrochemical Hydrogen Storage and Sensing

AU - Sarac, Baran

AU - Karazehir, Tolga

AU - Yüce, Eray

AU - Mühlbacher, Marlene

AU - Sarac, A. Sezai

AU - Eckert, Jürgen

N1 - Publisher Copyright: © 2021 American Chemical Society.

PY - 2021/2/18

Y1 - 2021/2/18

N2 - 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.

AB - 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.

KW - electrochemical hydrogen storage

KW - equivalent circuit model

KW - hydrogen sensing

KW - nanoporous

KW - Pd-metallic glass

KW - pseudocapacitance

KW - scanning electron microscopy

KW - thin films

UR - http://www.scopus.com/inward/record.url?scp=85102459730&partnerID=8YFLogxK

U2 - 10.1021/acsaem.0c03224

DO - 10.1021/acsaem.0c03224

M3 - Article

AN - SCOPUS:85102459730

VL - 4.2021

SP - 2672

EP - 2680

JO - ACS Applied Energy Materials

JF - ACS Applied Energy Materials

SN - 2574-0962

IS - 3

ER -