Reconstructing reaction kinetics via charge transfer complexes of polyaniline and TCBQ for high performance supercapacitors and electrochromic devices

Polyaniline (PANI) is one of the most promising materials for energy storage and electrochromic devices (ECDs). However, multiple redox cycles disrupt charge transfer behaviors besides PANI-depolymerization, severely deteriorating device's durability. Herein, a strategy is designed to reconstruct reaction kinetics through introducing tetrachlorobenzoquinone (TCBQ) and forming charge transfer complexes with an architecture of donor-acceptor, aiming to explore their application for supercapacitors and ECDs. Theoretical simulations reveal that: the bandgap of PANI/TCBQ decreases from 2.0 to ∼0.7 eV upon introduction of TCBQ, substantially increasing charge transport ability; Meanwhile, the reduction in LUMO energy level (from −3.1 to −3.9 eV) and the increase in HOMO energy level (from −5.2 to −4.7 eV) lower the redox energy barriers. Experiments confirm that TCBQ effectively protects PANI from depolymerization due to water attack, and strengthens the connection between PANI and substrate because the binding energy increases from 1.55 to 2.8 eV. Therefore, PANI/TCBQ supercapacitor maintains a high-capacity retention, up to 87.2% after 10,000 cycles. For ECDs, a light modulation of over 67% and a coloring efficiency of 76 cm2 C−1 are achieved, and the device performance is almost no decay after 100 cycles, suggesting that PANI/TCBQ possesses significant potential in both energy storage and electrochromic fields.