Fundamental study of Zn plating evolution at in-situ organic/inorganic interphase for practical Zn metal anodes

Engineering a functional layer to protect limited active Zn and ensure the stable plating/stripping is a facial and effective strategy for advancing the practical application of Zn metal-based energy storage system. Herein, we designed an artificial organic/inorganic hybrid layer (G/PAM) through the bridging of graphene and polyacrylamide (PAM), which is in-situ self-constructed via a spontaneous coprecipitation reaction. The polar PAM polymer shows a favorable affinity to water and Zn, which endows electrode with high Zn²⁺ accessibility and facilitates the de-solvation of hydrated Zn²⁺ clusters. The inorganic graphene phase provides a homogeneous Zn²⁺ flux and abundant nucleation sites by regulating the uniform distribution of the interfacial electric fields. The protection effect and Zn plating evolution at the hybrid interphase are emphasized combining theoretical calculations. Consequently, the modified electrode maintains a superior accumulated capacity of 1000 mAh cm⁻² at 5 mA cm⁻²/1 mAh cm⁻² with a high average CE of 99.72%. The as-fabricated full cell with limited Zn displays a long lifespan of 1800 cycles with a high discharge capacity of 119.8 mAh g⁻¹, which is competitive with the reported state-of-the-art studies. The as-proposed in-situ protective strategy presents a fresh and clear understanding of Zn plating evolution at the electrode/electrolyte interface.