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Abstract Developing promising solid‐state Li batteries with capabilities of high current densities have been a major challenge partly due to large interfacial resistance across the electrode/electrolyte interfaces. This work represents an integrated network of self‐standing polymer electrolyte and active electrode materials with in situ UV cross‐linking. This method provides a uniform morphology of composite polymer electrolyte with low thickness of 20–40 μm. This modification leads to promising cycling results with 85% specific capacity retention in Li||LiFePO4cell over 100 cycles at high current densities of 170 mA g−1(~25 μA cm−2, 1 C).By applying this method, the interfacial resistance decreases as high as seven folds compared to noncross‐linked interfaces. The following work introduce a facile and cost‐effective method in developing fast‐charging self‐standing polymer batteries with enhanced electrochemical properties. image
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Probing the electrical double layer by operando X‐ray photoelectron spectroscopy through a graphene‐carbon nanotube composite window
Abstract The electrical double layer is known to spontaneously form at the electrode‐electrolyte interface, impacting many important chemical and physical processes as well as applications including electrocatalysis, electroorganic synthesis, nanomaterial preparation, energy storage, and even emulsion stabilization. However, it has been challenging to study this fundamental phenomenon at the molecular level because the electrical double layer is deeply “buried” by the bulk electrolyte solution. Here, we report a quantitative probing of the electrical double layer of ionic liquids from the solid side of a photoelectron‐transparent graphene‐carbon nanotube hybrid membrane electrode using X‐ray photoelectron spectroscopy. The membrane window is ultrathin (1‐1.5 nm), large (~1 cm2), and robust, enabling a tight seal of the electrolyte and quantitative measurement with excellent photoelectron signals. Byoperandomonitoring the population changes of cations and anions in response to the applied electrical potentials, we experimentally resolve the chemical structure and dynamics of the electrical double layer, which corroborate results from molecular dynamics simulations. image
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- Award ID(s):
- 1626288
- PAR ID:
- 10457923
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- EcoMat
- Volume:
- 2
- Issue:
- 2
- ISSN:
- 2567-3173
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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