Scanning Probe Microscopy on Polymer Solar Cells

Abstract

Polymer solar cells have the potential to become a major electrical power generating tool in the twenty-first century. Research and development endeavors are focusing on continuous roll-to-roll printing of polymeric or organic compounds from solution—like newspapers—to produce flexible and lightweight devices at low cost. It is recognized, though, that besides the functional properties of the compounds, the organization of structures on the nanometre level— forced and controlledmainly by the processing conditions applied—determines the performance of state-of-the-art polymer solar cells. In such devices the photoactive layer is composed of at least two functional materials that form nanoscale interpenetrating phases with specific functionalities, a so-called bulk heterojunction. In this study, we discuss our current knowledge of the main factors determining the morphology formation and evolution—based on systematic scanning probe microscopy studies—and gaps in our understanding of nanoscale structure–property relations in the field of high-performance polymer solar cells are addressed.