Dimensionality-Reduction Regulation of C@M-Zn2SnO4(H+) for High-Capacity and Durable Lithium-Ion Battery Anodes

Abstract

Zn2SnO4 is a promising anode for lithium-ion batteries owing to its high theoretical capacity, yet its practical utilization is severely limited by sluggish reaction kinetics, large volume expansion, and unstable electrode/electrolyte interfaces. Here, we introduce a dimensionality-reduction strategy that simultaneously boosts capacity and cycling stability. Through surfactant-directed crystal growth, acid-etching reconstruction, and hydrothermal carbon coating, compact Zn2SnO4 octahedra are controllably transformed into sheet-assembled structures and finally into a core–shell composite with a continuous carbon layer (C@M-Zn2SnO4 (H+)). The continuous structural evolution shortens Li+ diffusion paths, buffers mechanical stress, and stabilizes the solid–electrolyte interface without altering the intrinsic lithium-storage mechanism of Zn2SnO4. As a result, the optimized C@M-Zn2SnO4 (H+) electrode delivers a reversible capacity of 650 mAh g−1 after activation and retains 620 mAh g−1 after 600 cycles at 200 mA g−1, with Coulombic efficiency approaching 100% throughout. This work demonstrates that dimensionality-reduction-assisted structural engineering is an effective strategy for developing high-capacity, long-cycle-life anode materials.