We present a Kelvin Probe Force Microscopy (KPFM) study on the topography combined with surface potential of hybrid poly(3-hexylthiophene)(P3HT):TiO2 nanorod materials in dark and under illumination. The hybrid materials with. ne and coarse phase separation are displayed. The photo-induced electron accumulation on surface is pronounced under high loading TiO2 nanorod in the blend. Large surface roughness, large surface height difference and potential variation in the hybrid P3HT:TiO2 nanorod are present with high content TiO2. Additionally, the incorporating a TiO2 nanorod layer on the surface of hybrid layer to facilitate collecting the electron and blocking the hole is investigated. (C) 2009 Elsevier B. V. All rights reserved.