Activating Aromatic Rings as Na-Ion Storage Sites to Achieve High Capacity

Abstract

A metal-organic compound designed with an extremely stable 3D openframework structure enables the aromatic rings in organic ligand to be activated as Na + storage redox sites. A large number of aromatic structures can be constructed into a 3D metal-organic framework for high-capacity electrode materials.

Bottom‐Up Fabrication of 1D Cu‐based Conductive Metal–Organic Framework Nanowires as a High‐Rate Anode towards Efficient Lithium Storage

“…The characteristicp eaks located in the size range from approximately 1.4 to 1.8 nm in the micropore size-distribution plot, which is obtained from the nonlocalized DFT, should be relatedt ot he contributionf rom hexagonal pores on the ab plane in the Cu-CATNWs. [21] In contrast, the O1ss pectrum ( Figure S1 c in the Supporting Information) suggestst hat the BEs for O=C, OÀC, and OÀCu do not change with cycling, whereas the relative contents of the OÀCu and OÀCg roups decrease to approximately 11.5 and 14.5 at %, respectively,a long with the O=Cg roup increasingt oa pproximately 18.8 at %, confirming that O=Ci sn ot the Li + storages ite. [21] Besides this, the large broad peak appearing at approximately 0.74 Vi nt he first negative sweep and then disappearing in the following sweeps is reasonably ascribed to the formation of as olid electrolyte interphase (SEI) film.…”

“…[20] Remarkably,t he XPS observations here are in good agreement with the previously reported Cu-based MOFs. [21] Besides this, the large broad peak appearing at approximately 0.74 Vi nt he first negative sweep and then disappearing in the following sweeps is reasonably ascribed to the formation of as olid electrolyte interphase (SEI) film. Ac ombination of type Ia nd IV is observed, revealing the coexistence of micro-and mesopores in the NWs, which can be fully supported by the mesopore size-distribution profile (Figure 3b)a nd micropore distribution data (the inset in Figure 3b).…”

“…Benefiting from the appealing structural features, as discussed above,t he resulting Cu-CATN Ws can be expected to have promisinga pplications in LIBs as ac ompetitive anode.T oe xplore the electrochemical Li storage performance of the Cu-CATN Ws, we first conducted cyclic voltammetry (CV) tests within the electrochemical windowf rom 0.01 to 3.0 V( vs. Li/ Li + )a t as can rate of 0.1 mV s À1 .Apair of sharp redox peaks at approximately 0.06 V, as displayed in Figure4a, can be correlated to the electrochemical reaction of Li + ions with conductive acetylene black (AB), whichh as been proved by Huang and co-workers. [21] Thus, it is easy to draw ac onclusion that the Li + storagem echanism of Cu-CATNWs mainlylies in the reversible Li + insertion/desertion in the aromatic C 6 ring and pore channels. [22] The smooth peaks between 1.0-1.5 Vs hould correspond to Li insertion into the aromatic C 6 ring moieties in the Cu-CAT anode.…”

Molecular Design Strategies for Electrochemical Behavior of Aromatic Carbonyl Compounds in Organic and Aqueous Electrolytes

“…[174,175,180] Zn 2+ is a strong Lewis acid that can form stable coordination bonds with electron-donating ligands. The cations act as central atoms that combine with oxygen in one or more ligands to form a coordination compound.…”

“…The essence of the electrochemical reaction of the carbonyl group is the nucleophilic addition reaction. Reproduced with permission [180] Copyright 2018, Elsevier. Therefore, the proper binding force and bond length of the LiO bond keeps the binding and disengagement rate of Li and O relatively stable.…”