Guangdong Research Center for Interfacial Engineering of Functional Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, China.
College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China.
Angew Chem Int Ed Engl. 2023 Mar 27;62(14):e202218922. doi: 10.1002/anie.202218922. Epub 2023 Feb 21.
Ion insertions always involve electrode-electrolyte interface process, desolvation for instance, which determines the electrochemical kinetics. However, it's still a challenge to achieve fast ion insertion and investigate ion transformation at interface. Herein, the interface deprotonation of NH and the introduced dissociation of H O molecules to provide sufficient H O to insert into materials' structure for fast energy storages are revealed. Lewis acidic ion-NH can, on one hand provide H O itself via deprotonation, and on the other hand hydrolyze with H O molecules to produce H O . In situ attenuated total reflection-Fourier transform infrared ray method probed the interface accumulation and deprotonation of NH , and density functional theory calculations manifested that NH tend to thermodynamically adsorb on the surface of monoclinic VO , and deprotonate to provide H O . In addition, the inserted NH has a positive effect for stabilizing the VO (B) structure. Therefore, high specific capacity (>300 mAh g ) and fast ionic insertion/extraction (<20 s) can be realized in VO (B) anode. This interface derivation proposes a new path for designing proton ion insertion/extraction in mild electrolyte.
离子插入总是涉及电极-电解质界面过程，例如去溶剂化，这决定了电化学动力学。然而，实现快速离子插入并研究界面处的离子转化仍然是一个挑战。本文揭示了 NH 的界面去质子化和引入的 H O 分子的解离，以提供足够的 H O 插入材料结构中，实现快速储能。路易斯酸性离子-NH 一方面可以通过去质子化提供 H O 本身，另一方面可以与 H O 分子水解生成 H O 。原位衰减全反射-傅里叶变换红外光谱法探测到 NH 的界面积累和去质子化，密度泛函理论计算表明 NH 倾向于热力学吸附在单斜 VO 的表面，并去质子化提供 H O 。此外，插入的 NH 对稳定 VO（B）结构有积极作用。因此，VO（B）阳极可以实现高比容量（>300 mAh g）和快速离子插入/提取（<20 s）。这种界面推导为在温和电解质中设计质子离子插入/提取提供了一条新途径。
