Single nanowire photovoltaics.

This tutorial review focuses on recent work addressing the properties and potential of semiconductor nanowires as building blocks for photovoltaic devices based on investigations at the single nanowire level. Two central nanowire motifs involving p-i-n dopant modulation in axial and coaxial geometries serve as platforms for fundamental studies. Research illustrating the synthesis of these structural motifs will be reviewed first, followed by an examination of recent studies of single axial and coaxial p-i-n silicon nanowire solar cells. Finally, challenges and opportunities for improving efficiency enabled by controlled synthesis of more complex nanowire structures will be discussed, as will their potential applications as power sources for emerging nanoelectronic devices.