The research results of Hainan University (HNU) Professor Wen Wei's team were recently published in the journal Nano Letters, with HNU listed as the main contributor. The team's research has broken new ground in the research and development of high-performance hydrogen ion batteries.

Hydrogen ions are well-suited for energy storage due to their smallest radius. However, hydrogen ions usually exist in the form of hydronium ion (H3O+) because of its high dehydration energy; the choice of electrode materials is thus limited to open frameworks and layered structures with large ionic channels.

Overcoming the extremely high dehydration energy of hydronium ions is the key to developing high-performance hydrogen ion batteries, which has proved to be a major challenge.

The research carried out by Wen's team revealed the phenomenon of surface-induced hydronium ion desolvation. It was found that the high-energy surface of anatase titanium dioxide (001) can promote the desolvation of hydronium ions, enabling the H+ intercalation with a strain-free characteristic. Proton batteries made in this way deliver a high specific energy at an ultrahigh specific power, the highest value among reported hydrogen ion batteries.

The discovery sheds light on the interactions between ions and electrodes, and brings new potential to the realm of battery optimizations.

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Cartoon schematic diagram of surface structure inducing desolvation of hydronium ion.