查看文章

A high-performance “green” carbon-based supercapacitor electrode material is synthesized from selected algae microspheres, which are grown under controlled cultivation conditions. The best-performing sample possesses a high specific surface area of 1337.9 m2 g−1 with a hierarchically porous structure and naturally intrinsic nitrogen dopant. This leads to an excellent specific capacitance of 353 F g−1 at 1 A g−1 and 92% capacitance retention even after 10 000 charge–discharge cycles at 20 A g−1, which makes it superior to many recently reported biomass- and synthetically derived carbon electrode materials. It is found that residual nitrogen and metal contents in algae-derived carbon are highly influenced by biomass components, such as proteins. The content of these components can be controlled by adjusting the concentrations of nutrients in cultivation media. However, nitrogen in algae proteins is not …