Structure Design of Bipolar Conjugated Porous Polymer Electrodes for High‐Performance Aqueous Symmetric All‐Organic Batteries
Qiben Tang, Zhiqiang Luo, Han Yan, Yinxu Wang, Boning Han, Ning Zhang
Abstract
Abstract Aqueous symmetric all‐organic batteries (ASAOBs) have received great attention due to their intrinsic safety, cost‐effectiveness, and material abundance. However, they generally suffer from poor electrochemical performances due to the large Coulombic repulsion stemming from the asymmetric number of negative (n)‐type and positive (p)‐type functional groups within the bipolar conjugated porous polymer (CPP) electrodes. Herein, three triphenylamine‐anthraquinone fused CPPs with different n/p molar ratios (i.e., 1:0.5, 1:1, and 1:1.5) are designed, and the effect of Coulombic repulsion on their capacity and reaction kinetics is systematically investigated. Among them, the as‐designed CPP with n:p = 1:1 (denoted as TNAQ) can significantly counteract the Coulombic repulsion in the internal structure, favoring the efficient (de)intercalation of cation (H + ) and anion (SO 4 2− ) charge carriers, which has been elucidated by experimental characterizations and theoretical computations. Moreover, the TNAQ electrode manifests excellent electrical/ionic conductivity and pseudocapacitance behavior, enabling fast reaction kinetics. Consequently, the TNAQ electrode exhibits reversible capacities of 80.3 and 83.5 mAh g −1 for the H + and SO 4 2− storage at 1 A g −1 , respectively. Moreover, the assembled TNAQ‐based ASAOBs deliver a considerable capacity of 57.4 mAh g −1 with 81.5% capacity retention over 5000 cycles at 10 A g −1 , showing promise in practical applications.