Biomass-derived mesopore-dominant porous carbons with large specific surface area and high defect density as high performance electrode materials for Li-ion batteries and supercapacitors.

Nano Energy 36 (2017) 322–330

Jin Niu, Rong Shao, Jingjing Liang, Meiling Dou, Zhilin Li, Yaqin Huang, Feng Wang⁎

Abstract: Porous carbons with high specific surface area and high defect density have been prepared through direct carbonization of cattle bones without any additional activators and templates. Benefiting from self-activation induced by hydroxyapatites within the cattle bones, the high-defect porous carbons obtained at 1100 °C (PC- 1100) possess the high specific surface area (2096 m² g^-1), largest mesopore volume (1.829 cm³ g^-1), a narrow mesopore size distribution centered at approximately 4.0 nm and good electrical conductivity (5141 S m^-1). Due to the synergistic effect of the defects and pores, PC-1100 as the anode for Li-ion battery exhibits a high reversible capacity of 1488 mA h g^-1 after 250 cycles at 1 A g^-1 and 661 mA h g^-1 after 1500 cycles at 10 A g^-1. Even at 30 A g^-1, PC-1100 can still deliver a high reversible capacity of 281 mA h g^-1, showing superior lithium storage capability. Moreover, the symmetric supercapacitor based on the PC-1100 in neat EMIM-BF4 electrolyte delivers a high energy density of 109.9 W h kg^-1 at a power density of 4.4 kW kg^-1, and maintains an energy density of 65.0 W h kg^-1 even at an ultrahigh power density of 81.5 kW kg^-1, as well as a superior cycling performance (96.4% of the capacitance retention after 5000 cycles).