P3HT:Fullerene-Based Composite as Active Layer for Optoelectronic Applications

In order to improve the charge transport properties and interface qualities of polymer-based devices, different acceptor materials are used in the photoactive layer of the organic photodetectors. In a similar context to creating high-performance photodetectors, the bulk heterojunction is formed by combining P3HT matrix with fullerene and its derivative to compare the optical and electrical properties of all the devices. The structure of the device is ITO/PEDOT:PSS/P3HT:fullerene/TiO₂/Al where fullerene refers to different acceptors like C₆₀, ICBA and PCBM. The improved morphology is confirmed by field-emission scanning electron microscopy and also verified by calculating the increased grain sizes of approximately 0.48 µm and 0.44 µm for ICBA and PCBM, respectively. Also, increased absorption is observed in the case of the PCBM nanocomposite obtained from UV spectroscopy analysis. The responsivity for the P3HT:PCBM composite is 8.5 mA/W, much higher than the ICBA- and C₆₀-based photodetectors (PDs). Overall, the performance of the PCBM- and ICBA-based PDs is improved, rendering them suitable for a wide range of applications in the field of optoelectronics.