Revealing bimetallic synergy in van der Waals AgInP2Se6 nanosheets for alkali metal ion battery electrodes

Abstract

We report two-dimensional AgInP2Se6 (AIPSe) bimetallic phosphorus trichalcogenides nanosheets as anodes for advanced alkali metal ion batteries (AMIBs). The intrinsic layered architecture of this compound not only facilitates rapid charge propagation but also accentuates ion storage due to its expansive surface area. The integration of the bimetallic component results in a synergistic enhancement in electronic/ionic conductivity and optimizes the redox dynamics of multi-electronic materials, eventually attaining superior electrochemical characteristics. Moreover, the accompanying deposition of metallic silver during electrochemical processes reduces battery polarization, while the presence of metallic indium acts as an efficacious structural stabilizer, effectively inhibit dendrite proliferation. As an anode electrode coupled with graphite (G) in lithium-ion (LIBs) and potassium-ion batteries (PIBs), AIPSe@G anodes for LIBs achieve 707.8 mA h g−1 at 0.1 A g−1, retain over 900 cycles at 2.0 A g−1, and demonstrate 318.5 mA h g−1 at 3.0 A g−1 rate capability. For PIBs, they reach 480.3 mA h g−1 at 25.0 mA g−1, sustains for 550 cycles at 250 mAg−1, and offers 214.2 mA h g−1 at 3.0 A g−1 rate performance. Comprehensive full cell tests further endure 100 cycles in both LIBs and PIBs under diverse current regimes. Our study pioneers a new direction for AMIB anode materials, emphasizing the advantages of integrating bimetallic features into two-dimensional frameworks to boost electrode dynamics and achieve consistent conversion reactions.