For energy storage system, it is still a huge challenge to achieve high energy density and high power density simultaneously. One potential solution is to fabricate electrochemical capacitors (ECs), which store electric energy through surface ion adsorption or redox reactions. Here we report a new electrode material, heavy nitrogen-doped (9.29 at.%) black titania (TiO_2−x:N). This unique hybrid material, consisting of conductive amorphous shells supported on nanocrystalline cores, has rapid N-mediated redox reaction (TiO_2−xN_y + zH⁺ + ze⁻ ↔ TiO_2−xN_yH_z), especially in acidic solutions, providing a specific capacitance of 750 F g⁻¹ at 2 mV s⁻¹ (707 F g⁻¹ at 1 A g⁻¹), great rate capability (503 F g⁻¹ at 20 A g⁻¹), and maintain stable after initial fading. Being a new developed supercapacitor material, nitrogen-doped black titania may revive the oxide-based supercapacitors.

对于储能系统，同时实现高能量密度和高功率密度仍然是巨大的挑战。一种潜在的解决方案是制造电化学电容器（EC），该电容器通过表面离子吸附或氧化还原反应存储电能。在这里，我们报告了一种新的电极材料，重氮掺杂（9.29 at。％）的黑色二氧化钛（TiO _{2- x}：N）。这种独特的杂化材料由支撑在纳米晶核上的导电无定形壳组成，具有快速的N介导的氧化还原反应（TiO _{2− x} N _y + z H ⁺ + ze ⁻ TiO _{2− x} N _y H _z），特别是在酸性溶液中，提供了750 F G的特定电容^-1在2毫伏小号^-1（707 F G ^-1 1 A G ^-1），大倍率性能（503 F G ^-1在20甲克^-1），并在初始衰落后保持稳定。作为一种新型的超级电容器材料，掺氮黑二氧化钛可能会使基于氧化物的超级电容器复活。