A review of perovskite solar cells with a focus on wire-shaped devices

Solar energy is clean and practically inexhaustible. The science of converting this clean, abundant energy into the usable form of electricity is known as photovoltaics, and is a large area of focus in science today. Perovskite solar cells have rapidly surpassed both dye sensitized solar cells and quantum dot solar cells in performance, which have made them a spot light in the solar cell research arena. Despite the widespread focus on perovskite material for energy harvesting, one should notice most research devices are on rigid flat substrates, limiting their application potential. Wire-shaped photovoltaic devices could prove to be pivotal in the niche area of integrated power systems in composites and other fabric applications. However, wire-shaped devices greatly lag in performance in comparison to their planar counterparts. Herein is an investigation into the governing device mechanisms (independent of substrate geometry), the evolution from rigid to flexible substrates, and finally, recent progress on flexible wire-shaped devices, with a focus on perovskite. It is through this lens that we review common characterization techniques, hurdles to the realization of wire-shaped perovskite devices, and the future direction of wire-shaped photovoltaic technology.