Bioabsorbable fabrication of molybdenum nitride/carbon nanocomposites for supercapacitors and metal ion batteries with robust stability

Metal nitride is one of the best anode materials of the energy storage device; however, the low stability of the pure metal nitride limits its wide applications. In this work, a new method of bioabsorbable fabrication was developed for preparing molybdenum nitride that corporates into the porous carbon materials. The molybdenum ions in pollutions could be easily absorbed by Ligustrum quihoui, and the transportation, accumulation, and circulation of molybdenum ions in Ligustrum quihoui were studied. The obtained composite material of biochar and molybdenum nitride is employed as anode material of supercapacitors and batteries which exhibits good electrochemical performance, especially the rate and long lifespan aspects. Typically, it is found that the specific capacity is 344 F·g⁻¹ at current density of 0.5 A·g⁻¹ in 2 mol·L⁻¹ KOH, and the capacitance retention and coulomb efficiency are above 90% after 10,000 cycles. It should be noted that the novel approach combines fabricating anode materials with advanced nanostructure and suppressing the environmental problems with metal pollution at the same time.