Title: Simultaneous Dangling Bond and Zincophilic Site Engineering of SiNx Protective Coatings toward Stable Zinc Anodes

Authors: Jiaxian Zheng, Guoyin Zhu, Xin Liu, Hongxing Xie, Yangduo Lin, Ye Zeng, Yizhou Zhang*, Appala Naidu Gandi, Zhengbing Qi, Zhoucheng Wang*, and Hanfeng Liang*

Abstract: Metallic Zn is an appealing anode for aqueous Zn-ion batteries, but it suffers from corrosion and Zn dendrites. In this work, we develop a nonstoichiometric silicon nitride (SiN_x) film with specific defect sites, i.e., Si dangling bonds (Si DBs), to modify the surface property and thus to enhance the stability of Zn anodes. The Si DBs, together with zincophilic N sites with strong Zn affinity, are able to uniformly distribute Zn²⁺ ions on the anodes, enabling an even Zn deposition. Meanwhile, the electrochemically inert SiN_x films can also suppress the side reactions to achieve a high Coulombic efficiency. As a result, the SiN_x@Zn symmetrical battery possesses a long lifespan of more than 4600 h at 1 mA cm^–2. Our work highlights the importance of defect engineering of protective layers in inhibiting the uncontrollable growth of Zn dendrites for constructing high-performance Zn anodes.

Full-Link: https://pubs.acs.org/doi/10.1021/acsenergylett.2c02282