A black phosphorus/Ti₃C₂ MXene nanocomposite for sodium-ion batteries: a combined experimental and theoretical study

A black phosphorus (BP)/Ti₃C₂ MXene composite was prepared by compositing small BP nanoparticles with exfoliated Ti₃C₂ layers. When used as an anode for sodium-ion batteries, the BP/Ti₃C₂ composite electrode exhibited higher specific capacity and better electrode stability than a BP electrode and a Ti₃C₂ electrode. The results of experimental and density functional theory (DFT) calculations illustrated that the synergy of BP and Ti₃C₂ based on a stable interfacial interaction simultaneously reduces the resistances from both electron and Na⁺ transport, resulting in the impressive electrochemical performance of the BP/Ti₃C₂ composite in sodium-ion batteries. The synthesis process and research concept could also be extended for further application of MXene materials and studies on sodium-ion batteries.