Interfacial nanostructuring on the performance of polymer/TiO2 nanorod bulk heterojunction solar cells

This work presents polymer photovoltaic devices based on poly(3-hexylthiophene) (P3HT) and TiO 2 nanorod hybrid bulk heterojunctions. Interface modification of a TiO 2 nanorod surface is conducted to yield a very promising device performance of 2.20% with a short circuit current density (J sc) of 4.33 mA/ cm 2, an open circuit voltage (∨ oc) of 0.78 V, and a fill factor (FF) of 0.65 under simulated A.M. 1.5 illumination (100 mW/cm 2). The suppression of recombination at P3HT/TiO 2 nanorod interfaces by the attachment of effective ligand molecules substantially improves device performance. The correlation between surface photo voltage and hybrid morphology is revealed by scanning Kelvin probe microscopy. The proposed method provides a new route for fabricating low-cost, environmentally friendly polymer/inorganic hybrid bulk heterojunction photovoltaic devices.