Title: Computationally Predicted High-Throughput Free-Energy Phase Diagrams for the Discovery of Solid-State Hydrogen Storage Reactions

Abstract

The design of multinary solid-state material systems that undergo reversible phase changes via changes in temperature and pressure provides a potential means of safely storing hydrogen. However, fully mapping the stabilities of known or newly targeted compounds relative to competing phases at reaction conditions has previously required many stringent experiments or computationally demanding calculations of each compound’s change in Gibbs energy with respect to temperature, G(T). Here, we have extended the approach of constructing chemical potential phase diagrams based on ΔG_f(T) to enable the analysis of phase stability at non-zero temperatures. We first performed density functional theory calculations to compute the formation enthalpies of binary, ternary, and quaternary compounds within several compositional spaces of current interest for solid-state hydrogen storage. Temperature effects on solid compound stability were then accounted for using our recently introduced machine learned descriptor for the temperature-dependent contribution G^δ(T) to the Gibbs energy G(T). From these Gibbs energies, we evaluated each compound’s stability relative to competing compounds over a wide range of conditions and show using chemical potential and composition phase diagrams that the predicted stable phases and H2 release reactions are consistent with experimental observations. This demonstrates that our approach rapidly computes the thermochemistry of hydrogenmore » release reactions for compounds at sufficiently high accuracy relative to experiment to provide a powerful framework for analyzing hydrogen storage materials. This framework based on G(T) enables the accelerated discovery of active materials for a variety of technologies that rely on solid-state reactions involving these materials.« less

Authors:

Clary, Jacob M.  ^[1];

• Search DOE PAGES for author "Clary, Jacob M."
• Search DOE PAGES for ORCID "0000-0002-6144-759X"

Holder, Aaron M.  ^[2];

• Search DOE PAGES for author "Holder, Aaron M."
• Search DOE PAGES for ORCID "0000-0002-1878-1541"

Musgrave, Charles B.  ^[2]

• Search DOE PAGES for author "Musgrave, Charles B."
• Search DOE PAGES for ORCID "0000-0002-5732-3180"

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+ Show Author Affiliations

1. Univ. of Colorado, Boulder, CO (United States)
2. Univ. of Colorado, Boulder, CO (United States); National Renewable Energy Lab. (NREL), Golden, CO (United States)

Publication Date:

Mon Oct 19 00:00:00 EDT 2020

Research Org.:

National Renewable Energy Lab. (NREL), Golden, CO (United States); Energy Frontier Research Centers (EFRC) (United States). Center for Next Generation of Materials Design (CNGMD)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES); National Science Foundation (NSF); USDOE Office of Energy Efficiency and Renewable Energy (EERE), Transportation Office. Fuel Cell Technologies Office

OSTI Identifier:

1710187

Report Number(s):

NREL/JA-5K00-78277
Journal ID: ISSN 1944-8244; MainId:32194;UUID:5504a162-b199-4185-a118-a63eeb63eb17;MainAdminID:18790

Grant/Contract Number:  

AC36-08GO28308; CHEM 1800592; CBET 1806079; CBET 2016225; EE0008088

Resource Type:

Accepted Manuscript

Journal Name:

ACS Applied Materials and Interfaces

Additional Journal Information:

Journal Volume: 12; Journal Issue: 43; Journal ID: ISSN 1944-8244

Publisher:

American Chemical Society (ACS)

Country of Publication:

United States

Language:

English

Subject:

08 HYDROGEN; free-energy phase diagrams; density functional theory; hydrogen storage; chemical potential; high-throughput; solid-state chemistry; thermodynamic stability