Title: Novel thin/tunable gas diffusion electrodes with ultra-low catalyst loading for hydrogen evolution reactions in proton exchange membrane electrolyzer cells

Abstract

Proton exchange membrane electrolyzer cells (PEMECs) have received great attention for hydrogen/oxygen production due to their high efficiencies even at low-temperature operation. Because of the high cost of noble platinum-group metal (PGM) catalysts (Ir, Ru, Pt, etc.) that are widely used in water splitting, a PEMEC with low catalyst loadings and high catalyst utilizations is strongly desired for its wide commercialization. In this study, the ultrafast and multiscale hydrogen evolution reaction (HER) phenomena in an operating PEMEC is in-situ observed for the first time. The visualization results reveal that the HER and hydrogen bubble nucleation mainly occur on catalyst layers at the rim of the pores of the thin/tunable liquid/gas diffusion layers (TT-LGDLs). This indicates that the catalyst material of the conventional catalyst-coated membrane (CCM) that is located in the middle area of the LGDL pore is underutilized/inactive. Based on this discovery, a novel thin and tunable gas diffusion electrode (GDE) with a Pt catalyst thickness of 15 nm and a total thickness of about 25 um has been proposed and developed by taking advantage of advanced micro/nano manufacturing. The novel thin GDEs are comprehensively characterized both ex-situ and in-situ, and exhibit excellent PEMEC performance. More importantly, they achieve catalystmore » mass activity of up to 58 times higher than conventional CCM at 1.6 V under the operating conditions of 80 degrees C and 1 atm. This study demonstrates a promising concept for PEMEC electrode development, and provides a direction of future catalyst designs and fabrications for electrochemical devices.« less

Authors:

Kang, Zhenye ^[1]; Yang, Gaoqiang ^[1]; Mo, Jingke ^[1]; Li, Yifan ^[1]; Yu, Shule ^[1]; Cullen, David A.  ^[2];

• Search DOE PAGES for author "Cullen, David A."
• Search DOE PAGES for ORCID "0000-0002-2593-7866"

Retterer, Scott T.  ^[2];

• Search DOE PAGES for author "Retterer, Scott T."
• Search DOE PAGES for ORCID "0000-0001-8534-1979"

Toops, Todd J.  ^[2];

• Search DOE PAGES for author "Toops, Todd J."
• Search DOE PAGES for ORCID "0000-0002-3163-8539"

Bender, Guido ^[3]; Pivovar, Bryan S. ^[3]; Green, Jr., Johney B. ^[3]; Zhang, Feng -Yuan ^[1]

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+ Show Author Affiliations

1. Univ. of Tennessee, Knoxville, Tullahoma, TN (United States)
2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
3. National Renewable Energy Lab. (NREL), Golden, CO (United States)

Publication Date:

Fri Mar 09 00:00:00 EST 2018

Research Org.:

Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); National Renewable Energy Laboratory (NREL), Golden, CO (United States)

Sponsoring Org.:

USDOE Office of Energy Efficiency and Renewable Energy (EERE)

OSTI Identifier:

1436032

Alternate Identifier(s):

OSTI ID: 1433307; OSTI ID: 1630148

Report Number(s):

NREL/JA-5900-71307
Journal ID: ISSN 2211-2855

Grant/Contract Number:  

AC05-00OR22725; AC36-08GO28308

Resource Type:

Accepted Manuscript

Journal Name:

Nano Energy

Additional Journal Information:

Journal Volume: 47; Journal Issue: C; Journal ID: ISSN 2211-2855

Publisher:

Elsevier

Country of Publication:

United States

Language:

English

Subject:

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; 77 NANOSCIENCE AND NANOTECHNOLOGY; Ultra-low catalyst loading; Thin gas diffusion electrode; Hydrogen evolution reaction; High catalyst mass activity; Proton exchange membrane electrolyzer cell; 36 MATERIALS SCIENCE; ultra-low catalyst loading; thin gas diffusion electrode; hydrogen evolution reaction; high catalyst mass activity; proton exchange membrane electrolyzer cell