Rational Design of Solar Cells for Efficient Solar Energy Conversion

10Polymer Solar Cells – An Energy Technology for the Future

Alagar Ramar and Fu‐Ming Wang

Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology, Taiwan, R.O.C.

10.1 Introduction

Today solar cell research is enriched with novel materials, methods, and design concepts with the major goal of producing high efficiency devices. The discovery of the photovoltaic effect by Edmund Becquerel in 1839 led to serious research by scientists all over the world that blossomed into so‐called photovoltaic technology [1, 2]. Commercial silicon solar cells were developed in the 1950s and commercialized in the 1960s for use in the space industry. Even though the inorganic solar cells entered the market, the high cost and the related environmental issues necessitated that alternatives were explored to help supply worldwide energy need. After the fundamental studies on the optical and electronic properties of pentacene in the 1960s, Tang successfully fabricated the first organic photovoltaic device where the concept of the generation of excitons at donors and their separation at a donor–acceptor interface was introduced [3]. It was a major breakthrough in organic photovoltaic devices.

Later, the photo‐induced charge transfer from the conjugated polymer poly[2‐methoxy‐5‐(2‐ethylhexyloxy)]‐1,4‐phenylenevinylene (MEH‐PPV) to fullerene was first observed by Sariciftci et al., which suggested that the conjugated polymer could be used as the electron ...