Nanostructured polymer blends (P3HT/PMMA): Inorganic titania hybrid photovoltaic devices

We have fabricated a photovoltaic (PV) device based on the polymer blends of (poly(3-hexylthiophene) (P3HT)/polymethylmethacrylate (PMMA)) and inorganic TiO₂ nanorod bulk heterojunction. The optimized photovoltaic device with 1.6 wt% PMMA concentration has a power conversion efficiency of 0.65% under simulated AM 1.5 illumination (100 mW/cm²), which is 38% more efficient than the device without the incorporation of PMMA. Furthermore, the PMMA-included device gives a short-circuit current density of 2.57 mA/cm², an open-circuit voltage of 0.53 V, and a fill factor of 0.48. Our studies have shown that having optimal PMMA concentration in the photovoltaic devices helps to smoothen the surface of the hybrid thin film, broaden the absorption spectrum, and improve the electrical conductivity. The results implying improvement in cell performance can be illustrated using atomic force microscopy (AFM), a UV/vis spectrophotometer and electrical measurements.