Hierarchical porous carbon obtained from animal bone and evaluation in electric double-layer capacitors

Animal bone, an abundant biomass source and high volume food waste, had been converted into a hierarchical porous carbon in a simple two-step sustainable manner to yield a highly textured material. The structures were characterized by nitrogen sorption at 77 K, scanning electron microscopy and X-ray diffraction. The electrochemical measurement in 7 M KOH electrolyte showed that the porous carbon had excellent capacitive performances, which can be attributed to the unique hierarchical porous structure (abundant micropores with the size of 0.5–0.8 and 1–2 nm, mesopores and macropores with the size of 2–10 and 10–100 nm), high surface area (SBET = 2157 m2/g) and high total pore volume (Vt = 2.26 cm3/g). Its specific capacitance was 185 F/g at a current density of 0.05 A/g. Of special interest was the fact that the porous carbon still maintained 130 F/g even at a high current density of 100 A/g.

Graphical abstractA hierarchical porous carbon material was prepared with an animal bone using a natural template. Electric double layer capacitor electrodes prepared from the porous carbon exhibited exceptional ratio capability which demonstrated that the animal bone is a promising candidate precursor to prepare high performance porous carbon material.Figure optionsDownload full-size imageDownload as PowerPoint slideResearch highlights► Animal bone is applied for preparing porous carbon. ► The bone carbon has a novel hierarchical porous structure and high surface area. ► The porous carbon is applied as electrode materials in EDLC. ► It shows excellent electrochemical properties, especially the capacitive performance.