Recent Progress in Materials and Device Design for Semitransparent Photovoltaic Technologies

Semitransparent photovoltaic (STPV) solar cells offer an immense opportunity to expand the scope of photovoltaics to special applications such as windows, facades, skylights, and so on. These new opportunities have encouraged researchers to develop STPVs using traditional thin-film solar cell technologies (amorphous-Si, CdTe, and CIGS or emerging solar cells (organic, perovskites, and dye-sensitized). There are considerable improvements in both power conversion efficiency (PCE) and semitransparency of these STPV devices. This review studies the device structure of state-of-the-art STPV devices and thereby analyzes the different approaches toward maximizing the product of PCE and average visible transmittance. The origins of PCE losses during the opaque-to-semitransparent transition in the different STPV technologies are discussed. In addition, critical practical aspects relevant to all STPV devices, such as compatibility of the top transparent electrode with the device structure, buffer layer optimization, light management engineering, scale-up, and stability, are also reported. This overview is expected to facilitate researchers across different technologies to identify and overcome the challenges toward achieving higher light utilization efficiencies in STPVs. Remarkable improvements in the light utilization efficiencies (LUEs) of semitransparent photovoltaics (STPVs) call for an updated assessment of the state-of-the-art and their potential for real-life applications (windows, facades, and so on). This comprehensive review analyzes the materials and device-design progress in STPVs based on conventional thin-film (a-Si, CIGS, CdTe) and emerging (perovskites, organics, and dye-sensitized) solar cells.image