A stable polypyridinopyridine- red phosphorus composite as a superior anode material for long- cycle lifetime lithium- ion batteries

Red phosphorus (RP) is an attractive anode material for lithium-ion batteries (LIBs) owing to its relatively low-cost and non-toxic nature. Here, we synthesize a novel polypyridinopyridine-red phosphorus (PPyPy-RP) composite containing phosphorus-carbon (P-C) and phosphorus-oxygen-carbon (P-O-C) bonds by a simple one-step vaporization-condensation-conversion method. The resultant PPyPy-RP composite has been investigated further as an anode material for LIBs, which exhibits a high discharge specific capacity of 1870.2 mA h g(phosphorus)(-1) at 100 mA g(-1) after 100 cycles. In the meantime, a stable discharge specific capacity of 518.3 mA h g(phosphorus)(-1) within 2000 cycles is maintained at a higher current density of 5000 mA g(-1). This superior performance is attributed to the structural stability of the chemically bonded PPyPy-RP composite, which plays an important role in maintaining contact between the P and conductive polypyridinopyridine (PPyPy) during the electrochemical process.