Mesoporous nanocrystalline film architecture for capacitive storage devices
A mesoporous, nanocrystalline, metal oxide construct particularly suited for capacitive energy storage that has an architecture with short diffusion path lengths and large surface areas and a method for production are provided. Energy density is substantially increased without compromising the capacitive charge storage kinetics and electrode demonstrates long term cycling stability. Charge storage devices with electrodes using the construct can use three different charge storage mechanisms immersed in an electrolyte: (1) cations can be stored in a thin double layer at the electrode/electrolyte interface (non-faradaic mechanism); (2) cations can interact with the bulk of an electroactive material which then undergoes a redox reaction or phase change, as in conventional batteries (faradaic mechanism); or (3) cations can electrochemically adsorb onto the surface of a material through charge transfer processes (faradaic mechanism).
1. A nanostructured, mesoporous electrode, comprising:
an electrically conductive substrate;
at least one mesoporous, nanocrystalline material with a plurality of pores, said pores having nanocrystalline walls, said pores being flexible whereby strain associated with charging and discharging is alleviated; and
a nanoscale conducting material in contact with said mesoporous material and said conductive substrate.
2. The electrode of claim 1 , wherein the mesoporous, nanocrystalline material is selected from the group of materials consisting essentially of metal oxides, transition metal oxides and mixed metal oxides.
3. The electrode of claim 1 , wherein the nanoscale conducting material is selected from the group of materials consisting essentially of carbonaceous materials, graphene, carbon nanotubes, metal nanowires, and conducting polymers.
4. The electrode of claim 1 :
wherein the electrically conductive substrate comprises a base sheet with a plurality of vertical conductive pins, the base sheet and pins having a surface;
wherein said nanocrystalline and conductive materials are disposed on the surface of said pins and said base sheet.