Recently developed high-efficiency organic photoactive materials for printable photovoltaic cells: a mini review

• Discuss chemical structure design and correlate with device performance.
• Progress includes the use of fused rings systems, 2D-3D approaches, and balancing solubility and aggregation.
• Research with non-fullerene acceptors have led to efficiencies that surpass that of fullerene-based devices.

Organic photovoltaic materials have the potential to revolutionize the solar energy industry as they are compatible with printing technologies that produce thin, flexible solar cells. In order for such material to be commercially viable, high power conversion efficiency (PCE) is necessary. The PCE of organic photovoltaic cells is largely determined by the material in the photoactive layer. Many different structures and types of organic materials for the active layer have been explored, such as benzodithiophene-based polymers and fused-ring ladder-type molecules. In recent years PCE values have neared or exceeded the theorized lower PCE limit of 10% for commercialization. In this review, the authors explore organic electron donors and acceptors that have been developed in the past 3 years (2013–2016) and have led to high-efficiency photovoltaic devices. Ultimately, the steadily climbing PCE values in recent years and variety of materials producing high PCEs points to a bright future for this area of solar energy.