Mechanism Research on Excited-State Photoinduced Electron Transfer in a Pyrazine Derivative under an External Electric Field

In this study, a charge-transfer complex was formed between 3-(4-(di([1,1'-biphenyl]-4-yl)amino)phenyl) (dpTPA) and acenaphtho[1,2-b]pyrazine-8,9-dicarbonitrile (APDC) (dpTPAAP) that exhibited a wide range of charge-transfer absorption that extended to the near-infrared region. The rate of charge transfer as regulated by an external electric field (Fext) was quantitatively depicted using first-principles quantum mechanics. The results show that the rates of charge separation and charge recombination were affected by Fext and were distinctly susceptible to it in the forward direction. According to the Marcus rate analysis of the dpTPAAP system with different values of Fext, its influence needs to be considered when simulating electron transfer on the bulk and the interfaces in organic semiconductors. This work advances our knowledge of the impact of Fext on solar-cell-based photoactive materials and provides a means to design novelty devices.