Synergistic Engineering of Anthracene and Thiazolo[5,4‑d] Thiazole–Based Donor–Acceptor Conjugated Microporous Polymers with Heteroatom Adoption for Enhanced Energy Storage Capacity

Abstract

Conventional supercapacitor electrodes are often hampered by low energy density, limited cycle life, and inadequate electrical conductivity. In contrast, conjugated microporous polymers (CMPs) offer an emerging class of electrode materials that simultaneously provide high surface areas, robust structural integrity, and enhanced electronic conductivity. Herein, we present the rational design and synthesis of two novel donor–acceptor (D–A) conjugated microporous polymers (CMPs) featuring a high density of heteroatoms strategically embedded within the framework, namely ANPh-TzTz and ANTPh-TzTz, incorporating redox-active thiazolo[5,4 d]thiazole (TzTz) units as organic electrode for supercapacitor applications via a condensation reaction between 2,3,6,7,9,10-hexa-(4-formylphenyl) anthracene (ANPh-6CHO) or 4,4',4'',4'''-(anthracene-9,10-diylidenebis(methanediylylidene))tetrabenzaldehyde (ANTPh-4CHO) and dithiooxamide in N,N-dimethylformamide (DMF). Both materials have outstanding thermal stabilities and exhibit moderate Brunauer–Emmett–Teller (BET) surface areas. Electrochemical evaluation reveals that ANPh-TzTz CMP delivers an excellent specific capacitance of 541 F g-1 with a remarkable capacitance retention of 94% over extended cycling. Furthermore, symmetric coin cell devices constructed using ANPh-TzTz CMP as the active material exhibit outstanding electrochemical performance, achieving a high energy density of 16.1 Wh kg-1 at a power density of 705.9 W kg-1, along with a device-level capacitance of 220 F g-1. These results show how effective molecular engineering may be in creating next-generation CMP-based electrode materials and how promising they are for high-performance energy storage needs.