Here we report a simple, low-cost and environment friendly method, in which Black locust seed dregs and potassium ferrate (K₂FeO₄) are used as starting raw materials and activation agent. The hierarchically porous carbons (BDPC) with high special surface area and abundant mesopores (S_BET = 2010.1 m² g⁻¹ and V_meso = 1.457 cm³ g⁻¹) are obtained through hydrothermal treatment and chemical activation. The BDPC electrode exhibits excellent electrochemical performances by virtue of unique architecture and heteroatoms pseudocapacitance contribution. In the three-electrode system, the optimized carbon material (BDPC-2) achieves a high specific capacitance of 333 F g⁻¹ at 1 A g⁻¹ and displays the high rate capability (81.1% capacitance retention at 100 A g⁻¹) in 6 M KOH electrolyte. The symmetric supercapacitor based BDPC-2 exhibits energy density as high as 26.2 Wh kg⁻¹ (at a power density of 0.79 kW kg⁻¹) and excellent long-term cycling stability (only 8% decrease after 10,000 cycles) in 6 M KOH.

在这里，我们报告了一种简单，低成本且环境友好的方法，其中以刺槐黑渣和高铁酸钾（K ₂ FeO ₄）作为起始原料和活化剂。具有高比表面积和丰富中孔的分层多孔碳（BDPC）（S _BET  = 2010.1 m ²  g ^-1和V _meso  = 1.457 cm ³  g ^-1）是通过水热处理和化学活化获得的。BDPC电极凭借独特的结构和杂原子拟电容贡献而展现出出色的电化学性能。在三电极系统中，优化的碳材料（BDPC-2）在1 A g ^-1时实现了333 F g ^-1的高比电容，并显示出高倍率能力（在100 A g ^-1时的电容保持率为81.1％））在6 M KOH电解液中。基于对称超级电容器的BDPC-2在6 M KOH中表现出高达26.2 Wh kg ^-1的能量密度（在0.79 kW kg ^-1的功率密度下）和出色的长期循环稳定性（10,000次循环后仅降低8％） 。