Fabrication of high-performance moisture-electric generators via synergistic effect between CNTs and TiO2 on porous PU structure

A “root-like” dendritic colloid was used to attach carbon nanotubes (CNTs) and titanium dioxide (TiO2) onto polyurethane (PU) foam to prepare high-performance moisture-electric generators (MEGs). The hybrid filler coated polyvinylidene difluoride (PVDF) dendritic colloids illustrates a “filler-wrapped” structure, which enables the filler to be in direct contact with water and enhances the interaction with water. Grabbing the hybrid filler with PVDF dendritic colloids can significantly increase the content of hybrid filler in PU foam based MEG. To address the problems of few active functional groups of CNTs and high internal resistance of TiO2, a synergistic network is constructed by hybridization. Due to the synergistic effect between hydrophilic TiO2 and CNTs, excellent performance of the MEG is illustrated, including high open-circuit voltage (0.51 V), short-circuit current (47.3 μA). The power density and energy density can reach 32.21 μW∙cm−3 and 15.97 μWh∙cm−3, respectively. This work provides a new strategy for the moisture-electric generators.