Confining TiO₂ Nanotubes in PECVD-Enabled Graphene Capsules Toward Ultrafast K-Ion Storage: In Situ TEM/XRD Study and DFT Analysis.

ABSTRACT: Titanium dioxide (TiO₂) has gained burgeoning attention for potassium-ion storage because of its large theoretical capacity, wide availability, and environmental benignity. Nevertheless, the inherently poor conductivity gives rise to its sluggish reaction kinetics and inferior rate capability. Here, we report the direct graphene growth over TiO₂ nanotubes by virtue of chemical vapor deposition. Such conformal graphene coatings effectively enhance the conductive environment and well accommodate the volume change of TiO₂ upon potassiation/depotassiation. When paired with an activated carbon cathode, the graphene-armored TiO₂ nanotubes allow the potassium-ion hybrid capacitor full cells to harvest an energy/power density of 81.2 Wh kg^-1/3

SUBMITTER: Cai J 

PROVIDER: S-EPMC7770745 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature