Reed Leaves as a Sustainable Silica Source for 3D Mesoporous Nickel (Cobalt) Silicate Architectures Assembled into Ultrathin Nanoflakes for High-Performance Supercapacitors

Mesoporous 3D architectures of silicon dioxide, nickel silicate, and cobalt silicate are for the first time prepared by using reed leafs as a sustainable silica source. Due to the 3D mesoporous architecture, nickel and cobalt silicate allow efficient charge transfer and mass transport, while at the same time buffering the volume changes during ion lithiation/delithiation processes. Especially, the nickel silicate electrode with the mesoporous 3D architecture shows a high specific capacitance, a good rate capability, and cycling stability for electrochemical capacitors.