High-entropy-Inspired construction of two-dimensional metal phosphorus tri-selenides for superior-performance lithium-ion batteries

Two-dimensional (2D) metal phosphorus tri-selenide is stacked by van der Waals interaction with huge potential for lithium storage, but still not performed as well as anticipated as an electrode material in battery devices. Here, we present a facile solid-phase sintering approach combined with ultrasonically-assisted stripping to synthesize large-scale 2D (FeMnCoNiCu)PSe₃ (HEPSe₃) with high entropy. The incorporation of multi-cations effectively mitigates the issues associated with poor electrical conductivity and susceptibility to structural collapse observed in transition metal phosphorus tri-selenide materials. The well-designed HEPSe₃ exhibits a high discharge capacity reaching 728 mAh g⁻¹ after 250 cycles at a current density of 100 mA g⁻¹ in lithium-ion batteries, and a long-life time of 4000 cycles with a high capacity of 488 mAh g⁻¹ under high current density (10 A g⁻¹). It also performs an outstanding rate performance. Density functional theory computations demonstrate that the cooperative interactions among multiple cations within high entropy architectures substantially lower the ion migration energy barriers of HEPSe₃. Additionally, when comes to pouch-type full cell, the HEPSe₃ performs a gravimetric energy density of 382.1 Wh kg⁻¹. This study provides strong evidence to support the prospective applicability of HEPSe₃ in alkali-ion batteries, while representing significant advancements towards leveraging 2D metal phosphorus tri-selenide layered materials in energy storage devices.