Optical and morphological properties of different P3HT concentration

The discovery of conjugated polymer and bulk-heterojunction concept has gain many interest in the organic solar cell world. The main problem for organic solar cells is that the power conversion efficiency (PCE) is still considered low even though it is much more low cost compared to inorganic solar cell such as Silicon (Si). Poly (3-hexylthiophene)(P3HT) is known to be the best material used in photovoltaic due to its high hole mobility but it is still considered low compared to inorganic solar cells. The objective of this research is to investigate the effect of P3HT concentration towards the device performance. From the Uv-Vis results, the absorbance increase as the concentration increases. The roughness of the surface was measured and the results shows that a concentration of 2 mg/ml has the lowest reading of roughness while 6 mg/ml has the highest reading of roughness. The layer's thickness was also measured and the concentration of 3 mg/ml is the thickest out of all the layers while 6 mg/ml is the thinnest.