Modulating Electronic Structure with Linearly Fused Pyrazine Units for High-Voltage and Stable Zinc-Organic Batteries Cathode

Authors

Minjian Zhao, Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power, College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, China.
Libin Zhang, Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power, College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, China.
Jintao Wang, Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power, College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, China.
Kun Ding, Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power, College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, China.Follow
Haimei Liu, Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power, College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, China.Follow
Yonggang Wang, Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Institute of New Energy, Fudan University, Shanghai 200433, China.Follow

Document Type

Article

Corresponding Author(s)

Kun Ding(kunding@shiep.edu.cn);
Haimei Liu(liuhm@shiep.edu.cn);
Yonggang Wang(ygwang@fudan.edu.cn)

Abstract

High-voltage n-type organic cathode materials are critical for constructing zinc-organic batteries (ZOBs) with high energy density and long cycle life. However, the intrinsically unfavorable electronic structures and relatively high LUMO energy levels of most n-type materials often lead to sluggish kinetics, high solubility, and suboptimal discharge voltages (< 0.8 V). Here, we design a small molecule, quinoxalino[2',3':5,6]pyrazino[2,3-f][1,10]phenanthroline (DPQP), as a ZOB cathode by introducing locally electron-deficient motifs into the conjugated backbone of aromatic compounds. The linearly fused pyrazine units extending the pyrazine–benzene framework effectively optimize the electronic structure, thereby significantly enhancing the discharge voltage. Meanwhile, the expanded π-conjugated plane suppresses dissolution and accelerates charge-transfer kinetics. Benefiting from these features, the DPQP electrode exhibits an exceptional increase in average operating voltage from 0.61 V to 1.07 V (vs. Zn²⁺/Zn) at 0.1 A·g^-1, with an overpotential of only 140 mV. Notably, no discernible voltage decay occurs as the current density increases, indicating rapid and highly reversible redox kinetics. Furthermore, the DPQP cathode delivers outstanding cycling stability, maintaining over 2000 h of continuous operation at 0.1 A·g^-1 and retaining 82.5% of its capacity after more than 10,000 cycles at 10 A·g^-1. Remarkably, the DPQP electrode also demonstrates excellent tolerance to extreme temperatures, achieving stable electrochemical performance across a wide temperature range from -20 °C to 60 °C. In addition, a series of spectroscopic and microscopic characterizations confirm the highly reversible redox behavior and Zn²⁺ storage mechanism of the DPQP cathode.

Graphical Abstract

Keywords

aqueous zinc batteries, organic cathode, n-type materials, electronic structure design, high voltage

DOI

10.61558/2993-074X.3609

Online Date

3-31-2026

Recommended Citation

Minjian Zhao, Libin Zhang, Jintao Wang, Kun Ding, Haimei Liu, Yonggang Wang. Modulating Electronic Structure with Linearly Fused Pyrazine Units for High-Voltage and Stable Zinc-Organic Batteries Cathode[J]. Journal of Electrochemistry, doi: 10.61558/2993-074X.3609.