Conjugated Polymers and Their Applications in Organic Solar Cells

摘要

Fossil fuel alternatives, such as solar energy, are moving to the forefront in a variety of research fields. In recent years, polymer solar cells (PSCs) have attracted considerable attention due to their advantages of light weight, flexibility and large-scale manufacturing with low cost roll-to-roll process. The power conversion efficiency of conjugated polymers/fullerene solar cells has been increased from 1% in 1995 to over 9% recently. These great advances are mainly due to the development of conjugated polymers used as the electron-donating materials in bulk heterojunction solar cells. In this article, we firstly briefly introduce the device structures and principles of PSCs. Since the conjugated polymers can be roughly divided into three categories based on the constitution of the repeating unit: (a) homopolymer, (b) donor-acceptor (D-A) polymer, and (c) quinoid polymer. We then focus on the relationship between the structures of polymers and the photovoltaic performance, especially highlight the chemical structure evolution of the A units among D-A type polymers. By doing this, we strive to obtain some rules between the structures and the properties of conjugated polymers, which may provide some valuable information for the future materials exploitation.