Controllable Preparation of Eucommia Wood-Derived Mesoporous Activated Carbon as Electrode Materials for Supercapacitors.

Activated carbons (ACs) for supercapacitors were synthesized from Eucommia ulmoides Oliver (EUO) wood by HPO with systemic activation processes. The target structure of ACs could be prepared by adjusting the technological parameters. As the HPO concentration was 25%, the mass ratio of feedstocks to activator was 1:4, the activation time was 6 h, and the activation temperature was 400 °C, the obtained AC revealed a high specific surface area (2033.87 m·g) and well-developed mesoporous (the rate of mesoporous was 96.4%) with the best economic feasibility. Besides, it possessed excellent electrochemical performance: the maximum specific capacitance reached up to 252 F·g, the charging and discharging period was 3098.2 s at 0.2 A·g, and the retention rate of specific capacitance reached 92.3% after 10,000 cycles. This low temperature and convenience technology provide a valuable reference for synthesizing the EUO-based ACs, making high-value utilization on the EUO branches, and owning a broad application prospect in supercapacitors.