Engineering LDH-Derived LiCoMnO4 Spinel/MXene Heterostructures via a Dual-Tuning Strategy for Efficient Lithium Extraction from Low-Grade Brines

作者：Tianqin Huang, Pengrui Sun, Ruiqi Yong, Yan Wang, Ying Zhao, Chuhan Huang, Wei Zhou, Lifeng Ding, Lu Guo, Xianfen Wang, Meng Ding · 发表于：Green Energy & Environment · 年份：2026 · DOI：10.1016/j.gee.2026.03.019 · 被引用次数：2 · 研究领域：Extraction and Separation Processes、Advancements in Battery Materials、Advanced Battery Materials and Technologies

Electrochemical lithium extraction from low-grade salt lake brines is a sustainable approach to reliable and cost-efficient lithium supply, yet it is hindered by sluggish diffusion kinetics and the severe interference from competing Mg 2+ ions. This study proposes a “dual-tuned” strategy to engineer a high-performance electrode by simultaneously optimizing the intrinsic crystal architecture and the extrinsic conductive network. First, nanosized LiCoMnO 4 (LCMO) spinels (∼100 nm) were synthesized via a topotactic transformation from ultrathin Co-Mn-layered double hydroxide (LDH) precursors, effectively shortening ion diffusion paths. Second, these nano-spinels were integrated with Ti 3 C 2 T x MXene nanosheets to construct a 3D conductive framework that accelerates electron transport. The optimized 50%LCMO/MXene electrode achieved a superior lithium adsorption capacity of 188.55 mg g –1 (4.45 mmol g –1 ) and remarkable stability (87.6% retention over 200 cycles). Mechanistic investigations via ex - situ XPS and DFT revealed a distinct adsorption pathway: Li + undergoes bulk intercalation driven by reversible lattice volume evolution, while Mg 2+ is restricted to surface accumulation. Moreover, DFT analysis reveals that the Mn environment remains remarkably rigid. This local electronic rigidity minimizes the Jahn-Teller effect and Mn dissolution, providing a fundamental structural explanation for the electrode’s enhanced durability. A dual-tuned LCMO@MXene heterostructure is sy...