Organic polymer photovoltaic cells are becoming an extremely active research area to meet the urgent need for clean and renewable energy managements due to their potential applications as flexible, low cost and solution processable energy sources. Because of the characteristics of the bulk heterojunction (BHJ) and the disadvantages of traditional structure, makes the gradient-layered polymer: fullerene blend films has become a trend. Through controlling solvent evaporation time (natural layer) and adding a certain volume BCP (induced layer), P3HT: PCBM blend films with gradient-layered structure are achieved. Compared to the traditional bulk heterojunction P3HT: PCBM blend ?lm, it can offer nearly the same power conversion ef?ciency of solar cell. Two methods simplify solar cells technology, and play a positive role in the industrialization of polymer solar cells http://www.sjfcd.org/paperInfo.aspx?ID=1048
