Affiliation:
1. Department of Chemical Engineering School of Environmental and Chemical Engineering Shanghai University Shangda Road 99 Shanghai 200444 P. R. China
2. Institute for Carbon Neutralization College of Chemistry and Materials Engineering Wenzhou University Wenzhou Zhejiang 325035 P. R. China
Abstract
AbstractOrganic compounds are regarded as important candidates for potassium‐ion batteries (KIBs) due to their light elements, controllable polymerization, and tunable functional groups. However, intrinsic drawbacks largely restrict their application, including possible solubility in electrolytes, poor conductivity, and low diffusion coefficients. To address these issues, an ultrathin layered pyrazine/carbonyl‐rich material (CT) is synthesized via an acid‐catalyzed solvothermal reaction and homogeneously grown on carbon nanotubes (CNTs), marked as CT@CNT. Such materials have shown good features of exposing functional groups to guest ions and good electron transport paths, exhibiting high reversible capacity and remarkable rate capability over a wide temperature range. Two typical electrolytes are compared, demonstrating that the electrolyte of LX‐146 is more suitable to maximize the electrochemical performances of electrodes at different temperatures. A stepwise reaction mechanism of K‐chelating with C═O and C═N functional groups is proposed, verified by in/ex situ spectroscopic techniques and theoretical calculations, illustrating that pyrazines and carbonyls play the main roles in reacting with K+ cations, and CNTs promote conductivity and restrain electrode dissolution. This study provides new insights to understand the K‐storage behaviors of organic compounds and their “all‐temperature” application.
Funder
Shanghai Municipal Education Commission
National Natural Science Foundation of China
Subject
Biomaterials,Biotechnology,General Materials Science,General Chemistry