Cellulose-derived flake graphite as positive electrodes for Al-ion batteries
Due to renewable nature and rich carbon content, biomass resources provide an adequate source of raw materials for developing carbon materials. Biomass energy is a by-product of agricultural, industrial and forestry, and rational use of biomass is an important issue. For converting biomass into graphitized products, there are some critical problems in the traditional graphitization method, such as high cost, long-time processing, addition of catalyst impurities and environmental pollution. For addressing these problems effectively, here we present a high-efficiency method for graphitizing biomass materials in molten CaCl2 molten salt. Such method with advantages of low-temperature, environmentally-friendly and catalyst-free feature allows the amorphous carbon for being converted into highly graphitized products. The as-prepared graphite could be used as the positive electrodes in the rechargeable aluminum-ion batteries, and the results indicate an efficient strategy for sustainably utilizing biomass in a high value-added way.