State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Electrochemical Process and Technology for Materials, Beijing University of Chemical Technology, Beijing 100029, PR China.
State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Electrochemical Process and Technology for Materials, Beijing University of Chemical Technology, Beijing 100029, PR China.
J Colloid Interface Sci. 2022 Aug 15;620:24-34. doi: 10.1016/j.jcis.2022.03.110. Epub 2022 Mar 28.
Heteroatom-rich carbon materials deliver superior potassium storage capacity owing to the abundant active sites, but their stability and conductivity are damaged because of the numerous defects and distortion of π-conjugated system. In this work, we amended the adverse influences of heteroatoms on carbon materials through the B, N stabilization effect. Due to an amending effect of B atoms on the N-doped carbon matrix, the integrity of the carbon skeleton and stability of the system are significantly enhanced, and the undesirable defects are transformed into favorable active sites, resulting in the simultaneous improvement of K storage capacity, rate performance and cyclic stability. The stabilized materials have a highly reversible carbon structure and fast K transfer kinetics, leading to high reversible capacity (300 mA h g at 0.1 A g), good rate performance (107.2 mA h g at 10 A g) and superior cyclic stability (75.3 % capacity retention from cycle 11 to 2000 at 1 A g). Consequently, the constructed devices perform excellent energy densities of 158.8 and 40.7 Wh kg under power densities of 100 and 11250 W kg, respectively. This work proposes an effective strategy for significantly improving heteroatom-rich carbon materials, which broadens its application fields in high-performance potassium ion storage.
富杂原子碳材料由于丰富的活性位点而具有优异的钾存储能力，但由于大量的缺陷和π共轭体系的变形，其稳定性和导电性受到破坏。在这项工作中，我们通过 B、N 稳定化效应修正了杂原子对碳材料的不利影响。由于 B 原子对 N 掺杂碳基质的修正作用，碳骨架的完整性和系统的稳定性得到了显著增强，并且不理想的缺陷转化为有利的活性位点，从而同时提高了钾的存储容量、倍率性能和循环稳定性。稳定化材料具有高度可逆的碳结构和快速的 K 转移动力学，从而实现了高可逆容量（在 0.1 A g 时为 300 mA h g）、良好的倍率性能（在 10 A g 时为 107.2 mA h g）和优异的循环稳定性（在 1 A g 时从第 11 圈到第 2000 圈的容量保持率为 75.3%）。因此，所构建的器件在功率密度分别为 100 和 11250 W kg 时表现出优异的能量密度，分别为 158.8 和 40.7 Wh kg。这项工作提出了一种显著改善富杂原子碳材料的有效策略，拓宽了其在高性能钾离子存储中的应用领域。
