Holistically Optimizing Charge Carrier Dynamics Enables High-Performance Dye-Sensitized Solar Cells and Photodetectors.

ABSTRACT

Charge carrier events across organic electronics are ubiquitous, and the derived optimization plays a crucial effect on improving the performance of organic electronics. Herein, a two-dimensional material (Ti3C2Tx) is incorporated into titanium dioxide (TiO2) to impart the Ti3C2Tx/TiO2 hybrid film enriched hydroxy group distribution, defect-negligible surface, upshifted work function, and enhanced conductivity yet electron mobility versus the pristine TiO2 film. Therefore, intensified photon-harvesting ability, reduced charge carrier recombination, and efficient charge carrier collection are realized for dye-sensitized solar cells (DSSCs) based on the Ti3C2Tx/TiO2 hybrid photoanode relative to control ones. Consequently, the modified DSSCs based on Z907 deliver superior efficiencies of 10.39 and 29.68% under 100 mW/cm2 illumination and ∼1.9 mW/cm2 dim light, respectively, being the highest values of Z907-based DSSCs. However, control devices only obtain lower efficiencies of 8.06 and 23.91% when undergoing the abovementioned illumination. On the other hand, the self-powered homologous photodetectors with the hybrid film as an electron-transporting layer present enhanced detectivity (1.69 × 1011 Jones) and a shortened responsivity of 0.26 s versus that of control ones (1.39 × 1011 Jones and 0.35 s). Our work implies that the Ti3C2Tx/TiO2 hybrid film features high potential for improving the performance of organic electronics for its effect of holistically optimizing charge carrier dynamics.