Solar Trap-Adsorption Photocathode for Highly Stable 2.4 V Dual-Ion Solid-State Iodine Batteries.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 40767046.
- Also identified by DOI 10.1002/adma.202504492 and PMC identifier 12548518.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Rechargeable aqueous iodine-based electrochemical energy storage systems offer a cost-effective alternative to conventional alkali metal batteries for grid-scale applications. However, their practical deployment is hindered by sluggish iodine redox kinetics and the shuttle of polyiodides, which severely limit their lifespan. To address these challenges, a novel solid-state organic||I<sub>2</sub> battery leveraging a Co<sub>3</sub>O<sub>4</sub>-TiO<sub>2</sub> heterojunction photocathode is developed. By integrating a photo-assisted mechanism with an innovative device architecture, the system achieves accelerated iodine conversion kinetics, enhances iodide ion utilization, and enables a four-electron redox pathway. Theoretical calculation combined with electrochemical analysis reveals that the photo-assisted mechanism promotes electrostatic adsorption of polyiodides, accelerates interfacial charge transfer, and significantly improves iodine redox kinetics. As a result, the organic||I<sub>2</sub> battery delivers a high specific capacity of 1.36 mAh cm<sup>-2</sup>, a discharge voltage of 2.4 V, and excellent cycle stability over 1000 cycles, retaining 80.9% of its capacity at a current density of 10 mA cm<sup>-2</sup>. This photo-enhanced battery exhibits strong competitiveness compared to previously reported iodine-based batteries. The remarkable performance of this photo-assisted prototype offers a sustainable and cost-effective solution for next-generation energy storage.