Smart power system: Tuning energy storage by electrophoretic repositioning of TiO₂ nanoparticles in electrolytes.

An effective strategy for efficient use of power is to deliver variable energy whose level depends on the fluctuating demand. Electric double layer capacitors are regarded as one approach suitable for such power management systems. Prior investigations of TiO₂ nanomaterials have primarily focused on how they can be incorporated into a system’s electrodes and not its electrolytes. We demonstrate here that TiO₂ nanoparticles (NPs) dispersed directly into an electrolyte may also be an approach to smart energy storage applications. Cyclic voltammetry measurements are employed to explore charge storage capabilities and, together with repositioning of the TiO₂ and Al₂O₃ NPs in the electrolyte. TiO₂ NPs are revealed to be actively positioned to form a transient film on the electrode surface, significantly enhancing the system’s energy storage capabilities. In contrast, minimal enhancement is observed for the Al₂O₃. This study shows that TiO₂ NPs are intrinsically capable of being a component of a “smart power” system, designed to deliver variable power commensurate with a fluctuating demand.