π-Extended Dihydrophenazine-Based Polymeric Cathode Material for High-Performance Organic Batteries

Abstract

Organic electrode materials have attracted widespread attention as alternative candidates for lithium-ion batteries due to their potential for sustainable production, wide source, low cost, and adjustability. Herein, we develop a dihydrophenazine-based multielectron redox center to promote the energy and power density of organic batteries. The poly­(1,3,5-tris­(10-(4-vinylphenyl)­phenazin-5­(10H)-yl)­benzene) (p-TPZB)-based battery shows a specific discharge capacity of 155 mAh g–1 with a discharge voltage of 3.1–4.2 V (vs Li+/Li) initially. Until the 2000th cycle, the specific discharge capacity is still maintained up to 138 mAh g–1, with an excellent capacity retention rate of ca. 89% at 2C. Meanwhile, the p-TPZB|Li cell delivers outstanding power density and energy density up to 4320 W kg–1 and 522 Wh kg–1, respectively. Moreover, p-TPZB also has shown potential as an active material for sodium-ion batteries (SIBs). Our study provides a structure and strategy to improve the capacity and density of next-generation high-performance lithium/sodium-ion batteries.

Toward High‐Performance Dihydrophenazine‐Based Conjugated Microporous Polymer Cathodes for Dual‐Ion Batteries through Donor–Acceptor Structural Design

“…Recently, the p‐type dihydrophenazine (Pz) unit has attracted intense attention as redox‐active building block for constructing polymer cathodes in DIBs, owing to its high reversible redox reaction and high theoretical charge‐storage capacity. [ 5,20–24 ] The redox centers in Pz are the two nitrogen atoms with lone pair electrons, which endow Pz with a theoretical capacity up to 297 mAh g −1 and high discharge voltage higher than 3 V versus Li + /Li. Park et al for the first‐time reported the methyl‐ and benzene‐substituted Pz derivatives as the cathodes in lithium DIBs, and a high discharge capacity around 191 mAh g −1 was obtained.…”

“…The crosslinked structure was further proposed to solve the dissolution issue of Pz‐based polymer cathodes, expanding the cycling life to around 1000 cycles without obvious capacity fading. [ 22,23 ] In addition, it has been proved that the amorphous nature with crosslinked polymer chains could increase the kinetics of Pz‐based polymer cathodes. [ 22 ] However, most of the Pz‐based polymers still suffer from either low specific capacity or relatively poor rate performance, which might be attributed to the low conductivity of electrons and/or ions.…”

Facile Synthesis of Polyphenothiazine as a High‐Performance p‐Type Cathode for Rechargeable Lithium Batteries

“…The most well‐known p‐type organic cathode materials are conducting polymers (e. g., polyaniline, [11,12] polytriphenylamine, [13] and polypyrrole [14] ) and nitroxyl radical polymers (e. g., PTMA [15] ). In recent years, researchers’ interest also shifts to polymers based on various electroactive heteroaromatics, including N ‐substituted phenazine, [16–19] conjugated pyridine dimer, [20] phenothiazine, [18,21–31] phenoxazine, [32] and thianthrene [33,34] . A merit of these heteroaromatic units is that they are potentially able to deliver two electrons and thus achieve attractive capacity above 200 mAh g −1 .…”

Design strategies and applications of novel functionalized phenazine derivatives: a review

“…This further proved that polymeric aromatic amines could be used as electrode materials for metal ion batteries. Indeed, in 2020, Zhao et al 133 selected dihydrophenazine polymer 44 to construct organic electrode materials (Scheme 16). In the different types of heterocyclic aromatic compounds, dihydrophenazine derivatives greatly exhibited stable redox plateaus, which could act as basic units to furnish a new π-extended active center skeleton.…”