Superior rate and long-lived performance of few-layered black phosphorus-based hybrid anode for lithium-ion batteries

Black phosphorus (BP) is an attractive anode material for advanced lithium-ion batteries due to its intrinsic layered structure, high electrical conductivity and large theoretical capacity. However, the formation of an unstable solid-electrolyte interphase (SEI) and electrode pulverization caused by volume expansion during the lithiation-delithiation process have led to poor cycling stability. In this work, we report a ternary hybrid anode (BP-GO-PANI) prepared by a simple solvothermal reaction of BP and graphene oxide (GO), with the output coated in situ by polyaniline (PANI). The PANI coating ensures the stability of SEI and maintains smooth Li+ transmission paths, which enhances the initial Coulombic efficiency and rate performance. Furthermore, GO and PANI mitigate the volume expansion of electrodes and thereby improve cycling stability. The hybrid anode has a high reversible specific capacity of 652 mAh g−1 at 0.1 A g−1 after 50 cycles, which is 6.2 times higher than that of origin BP electrode. Furthermore, the hybrid anode also obtains credible cycle stability with a retained capacity of 958 mAh g−1 at 5 A g−1 after 2000 cycles. This convenient multi-step compounding method opens a pathway for the development of stable, high-performance alloyed anode materials.