Flexible Solar Cells Made of Nanowires/Microwires

This chapter focuses on progress in the development of flexible solar cells to reduce the weight and cost, to improve shock resistance and to facilitate transportation, storage, and installation, compared to conventional systems. Although many studies report flexible devices using thin films of organics, amorphous and polycrystalline Si, and other inorganic semiconductors, systems made with one-dimensional (1D) nano/microstructures of inorganic semiconductors with high crystallinity (even monocrystallinity) provide significant enhancement in energy conversion efficiency. This chapter also provides an overview of mechanically flexible solar cells made of nanostructures/microstructures of inorganic semiconductors, with a special emphasis on p-n junction and photoelectrochemical (PEC) systems. By employing dry transfer printing techniques and appropriate mechanical designs, intrinsically rigid and fragile semiconducting materials in bulk can be readily used as building blocks for flexible p-n junction solar cells. It reviews various recent approaches towards flexible PEC cells employing nanotubes and nanowires. Nanotubes/nanowires made of TiO2, ZnO, and Si either grown on or transferred onto flexible substrates represent promising photoanode materials for mechanically flexible PEC solar cells.