# Evaluation of the Interphase-Related Cycling Stability of Thin-Film Amino- and Hydroxy-Substituted Anthraquinone Electrodes for Sodium-Ion Batteries

## TL;DR

This paper evaluates organic cathode materials for sodium-ion batteries, identifying promising candidates with good cycle stability and environmental benefits.

## Contribution

The study systematically tests 12 amino- and hydroxy-substituted anthraquinone derivatives for sodium-ion battery cathodes, many of which are untested in such systems.

## Key findings

- 1,8-dihydroxy-anthraquinone and 1,8-diamino-anthraquinone show high cycle stability with 72% and 73% capacity retention over 100 cycles.
- Material solubility and structural properties strongly influence electrochemical performance.
- Several naturally occurring anthraquinone derivatives demonstrate potential for sustainable battery cathodes.

## Abstract

This study investigates sustainable approaches to designing
organic
cathode materials for sodium-ion batteries, aiming to replace traditional
metal-based electrodes. Organic materials present a promising alternative
due to their lower environmental impact, supply chain stability, and
tunable electrochemical properties. In this work, the electrochemical
performance of 12 commercially available amino- and hydroxy-substituted
anthraquinone derivatives, including several naturally occurring compounds,
was systematically evaluated in sodium-ion battery systems. By focusing
on readily available commercial materials, this study identified the
most stable and effective candidates for organic cathodes in sodium-ion
batteries. Notably, the majority of these derivatives have never been
tested in galvanostatic cycling in either lithium or other post-lithium
battery systems. Through systematic testing, challenges such as high
solubility and limited redox reactivity were addressed, demonstrating
how careful material selection can yield high-performance, long-cycle-life
organic cathodes. The performance of these materials was found to
be strongly influenced by their solubility in the electrolyte as well
as their structural and electronic properties, including electron-accepting
capabilities and sodium coordination behavior. Among the studied materials,
1,8-dihydroxy-anthraquinone and 1,8-diamino-anthraquinone demonstrate
superior cycle stability, maintaining 72% and 73% capacity retention,
respectively, over 100 charge–discharge cycles, followed by
1,5-diamino-anthraquinone and 1-hydroxy-anthraquinone with 64% and
66%. These findings not only advance the development of organic cathode
materials for sodium-ion batteries but also highlight the potential
of sustainable material choices to enable scalable and environmentally
friendly energy storage solutions, supporting the transition to a
greener energy future.