Chalcogen-doped red phosphorus nanoparticles @ porous carbon as high-rate and ultrastable anode for lithium-ion batteries

Abstract

A strategy of doping chalcogen-heteroatom in red phosphorus (RP) nanoparticles is adopted to improve the electrochemical performance of RP based composites as lithium storage materials. RP nanoparticles embedded in porous carbon with chalcogen-doping (S-, Se- and Te–P@PC) composites are synthesized via a facile evaporation-condensation approach. The large volume expansion of RP upon cycling is well mitigated by nanoscale feature and buffered by pore-closed carbon matrix. The extra fillings of chalcogen dopants lessen the specific surface areas of the doped composites, minimizing parasitic surface reactions of anode materials with electrolyte that can lead to high initial coulombic efficiencies. The high conductivity of Se dopant and the formed conductive Li–Se/Li–Se–P confer the Se–P@PC anode with improved electron/ion transport properties to deliver a superior fast-charging capability over 900 cycles. Moreover, a high-rate capacity of 908.5 mA h g−1 at 5.0 A g−1 and an impressive reversible capacity of 848.2 mA h g−1 even after 1800 cycles at 1.0 A g−1 of Se–P@PC surpass most of reported RP-based anode materials.