Metal–Organic Frameworks for Fast Electrochemical Energy Storage: Mechanisms and Opportunities

Abstract

Electrochemical energy storage devices are typically based on materials of inorganic nature which require high temperature synthesis and frequently feature scarce and/or toxic elements. Organic-based materials on the other hand can provide an attractive alternative, potentially yielding sustainable, safe, and cost-effective energy storage devices based on abundant elements (e.g. C, N, O, S, and H). However, attempts to incorporate organic and coordination compounds so far have led to sub-par cycling stability and charging rates due to insufficient structural and (electro)chemical stability, low electrical conductivity, and reduced performance at industrially relevant device scales. In recent years metal–organic frameworks (MOFs) have gained attention as having the potential to rival or even supersede traditional energy storage materials. Functional properties such as electronic or ionic conductivity can be incorporated into these materials by judicious design of their constituent inorganic and organic building blocks. However, full realization of the potential of MOFs for electrochemical energy storage requires joint expertise from distinct fields. In particular, bridges must be formed between electrochemists and synthetic and material chemists to establish the unified approach necessary to develop MOF-based energy storage devices exhibiting competitive performance.

Toward Ultrahigh‐Rate Energy Storage of 3000 mV s−1 in Hollow Carbon: From Methodology to Surface‐to‐Bulk Synergy Insights

“…[5][6][7] By contrast, electric double-layer capacitors (EDLCs) feature the merits of safe, DOI: 10.1002/smll.202308453 high power, and long life span stemming from reversible electrostatic adsorption/desorption mechanisms. [8][9][10] It is acknowledged that carbon materials with tunable structure, high conductivity, and low cost hold a promise for mass adoption in the future EDLCs industry. [11][12][13] Jiang and co-workers [14] constructed hierarchically porous carbon through pyrolysis of enzymolysis-treated wood, which delivers a high areal energy density of 0.21 mWh cm −2 .…”

Arresting dissolution of two-dimensional metal–organic frameworks enables long life in electrochemical devices

“…Two-dimensional conjugated metal-organic frameworks (2D cMOFs) are an emerging class of electrically conducting, porous crystalline materials. [1][2][3] Typically, 2D cMOFs host multitopic pconjugated aromatic ligands in square planar MX 4 (X = O, NH, or S) linkages that repeat and create porous 2D sheets. Various 2D cMOFs have been synthesized using ligands with core structures ranging from benzene [4][5][6][7][8][9][10][11][12] to larger structures [13][14][15][16][17] like triphenylene, [18][19][20][21][22] coronene, 23 phthalocyanine, 24,25 and hexacata-hexabenzocoronene.…”

“…[30][31][32][33][34][35][36][37] However, investigations into the factors that determine the electrochemical stability of 2D cMOFs and lead to their capacity loss during charge-discharge cycling are rare. 3 A comprehension of the degradation pathways in 2D cMOFs is crucial for devising strategies to enhance their stability, meeting the thresholds of thousands to hundreds of thousands of chargedischarge cycles needed for EES applications in batteries and supercapacitors, respectively.…”