skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Metal–Organic Frameworks as Highly Active Electrocatalysts for High-Energy Density, Aqueous Zinc-Polyiodide Redox Flow Batteries

Abstract

This paper presents MOFs serving as catalysts are applicable in zinc-ployioidide redox flow batteries.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE Office of Electricity Delivery and Energy Reliability (OE)
OSTI Identifier:
1324900
Report Number(s):
PNNL-SA-116994
Journal ID: ISSN 1530-6984; TE1400000
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nano Letters; Journal Volume: 16; Journal Issue: 7
Country of Publication:
United States
Language:
English

Citation Formats

Li, Bin, Liu, Jian, Nie, Zimin, Wang, Wei, Reed, David, Liu, Jun, McGrail, Pete, and Sprenkle, Vincent. Metal–Organic Frameworks as Highly Active Electrocatalysts for High-Energy Density, Aqueous Zinc-Polyiodide Redox Flow Batteries. United States: N. p., 2016. Web. doi:10.1021/acs.nanolett.6b01426.
Li, Bin, Liu, Jian, Nie, Zimin, Wang, Wei, Reed, David, Liu, Jun, McGrail, Pete, & Sprenkle, Vincent. Metal–Organic Frameworks as Highly Active Electrocatalysts for High-Energy Density, Aqueous Zinc-Polyiodide Redox Flow Batteries. United States. doi:10.1021/acs.nanolett.6b01426.
Li, Bin, Liu, Jian, Nie, Zimin, Wang, Wei, Reed, David, Liu, Jun, McGrail, Pete, and Sprenkle, Vincent. 2016. "Metal–Organic Frameworks as Highly Active Electrocatalysts for High-Energy Density, Aqueous Zinc-Polyiodide Redox Flow Batteries". United States. doi:10.1021/acs.nanolett.6b01426.
@article{osti_1324900,
title = {Metal–Organic Frameworks as Highly Active Electrocatalysts for High-Energy Density, Aqueous Zinc-Polyiodide Redox Flow Batteries},
author = {Li, Bin and Liu, Jian and Nie, Zimin and Wang, Wei and Reed, David and Liu, Jun and McGrail, Pete and Sprenkle, Vincent},
abstractNote = {This paper presents MOFs serving as catalysts are applicable in zinc-ployioidide redox flow batteries.},
doi = {10.1021/acs.nanolett.6b01426},
journal = {Nano Letters},
number = 7,
volume = 16,
place = {United States},
year = 2016,
month = 7
}
  • Large-scale energy storage systems are crucial for substantial deployment of renewable energy sources. Energy storage systems with high energy density, high safety, and low cost and environmental friendliness are desired. To overcome the major limitations of the current aqueous redox flow battery systems, namely lower energy density (~25 Wh L -1) and presence of strong acids and/or other hazardous, a high energy density aqueous zinc/polyiodide flow battery (ZIB) is designed with near neutral ZnI 2 solutions as catholytes. The energy density of ZIB could reach 322 Wh L -1 at the solubility limit of ZnI 2 in water (~7 M).more » We demonstrate charge and discharge energy densities of 245.9 Wh/L and 166.7 Wh L-1 with ZnI 2 electrolyte at 5.0 M, respectively. The addition of ethanol (EtOH) in ZnI 2 electrolyte can effectively mitigate the growth of zinc dendrite at the anode and improve the stability of catholytes with wider temperature window (-20 to 50°C), which enable ZIB system to be a promising alternative as a high-energy and high- safety stationary energy storage system.« less
  • Improved metal-based redox flow batteries (RFBs) can utilize a metal and a divalent cation of the metal (M.sup.2+) as an active redox couple for a first electrode and electrolyte, respectively, in a first half-cell. For example, the metal can be Zn. The RFBs can also utilize a second electrolyte having I.sup.-, anions of I.sub.x (for x.gtoreq.3), or both in an aqueous solution, wherein the I.sup.- and the anions of I.sub.x (for x.gtoreq.3) compose an active redox couple in a second half-cell.
  • New active materials are needed to improve the performance and reduce the cost of non-aqueous redox flow batteries (RFBs) for grid-scale energy storage applications. Efforts to develop better performing materials, which have largely been empirical, would benefit from a better understanding of relationships between structural, electronic and RFB-relevant functional properties. This paper focuses on metal-acetylacetonates, a class of metal coordination complexes that has shown promise for use in RFBs, and describes correlations between their experimentally measured standard potentials, solubilities, and stabilities (cycle lifes), and selected chemical, structural and electronic properties determined from Density Functional Theory (DFT) calculations. The training setmore » consisted of 16 complexes including 5 different metals and 11 different substituents on the acetylacetonate ligand. Standard potentials for those compounds were calculated and are in good agreement with experimentally measured results. A predictive equation based on the solvation energies and dipole moments, two easily computed properties, reasonably modeled the experimentally determined solubilities. Importantly, we were able to identify a descriptor for the stability of acetylacetonates. The experimentally determined stability, quantified as the cycle life to a given degree of degradation, correlated with the percentage of the highest occupied (HOMO) or lowest unoccupied molecular orbital (LUMO) on the metal of the complex. This percentage is influenced by the degree of ligand innocence (irreducibility), and complexes with the most innocent ligands yielded the most stable redox reactions. To this end, VO(acetylacetonate)(2) and Fe(acetylacetonate)(3), with nearly 80% of the HOMO and LUMO on the metal, possessed the most stable oxidation and reduction half-reactions, respectively. The structure-function relationships and correlations presented in this paper could be used to predict new, highly soluble and stable complexes for RFB applications.« less