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Organic solar cells have obtained a prodigious amount of attention in photovoltaic research due to their unique features of light weight, low cost, eco-friendliness, and semitransparency. A rising trend in this field is the development of all-small-molecules organic solar cells (ASM-OSCs) due to their merits of excellent batch-to-batch reproducibility, well-defined structures, and simple purification. Among the numerous organic photovoltaic (OPV) materials, benzodithiophene (BDT)-based small molecules have come to the fore in achieving outstanding power conversion efficiency (PCE) and breaking the 17% efficiency barrier in single-junction OPV devices, indicating the significant potential of this class of materials in commercial photovoltaic applications. This review specially focuses on up-to-date information about improvements in BDT-based ASM-OSCs since 2011 and provides an outlook on the most significant challenges that remain in the field. We believe there will be more exciting BDT-based photovoltaic materials and devices developed in the near future. [ABSTRACT FROM AUTHOR]

The short‐circuit current (Jsc) of organic solar cells is defined by the interplay of exciton photogeneration in the active layer, geminate and non‐geminate recombination losses and free charge carrier extraction. The method proposed in this work allows the quantification of geminate recombination and the determination of the mobility‐lifetime product (µτ) as a single integrated parameter for charge transport and non‐geminate recombination. Furthermore, the extraction efficiency is quantified based on the obtained µτ product. Only readily available experimental methods (current‐voltage characteristics, external quantum efficiency measurements) are employed, which are coupled with an optical transfer matrix method simulation. The required optical properties of common organic photovoltaic (OPV) materials are provided in this work. The new approach is applied to three OPV systems in inverted or conventional device structures, and the results are juxtaposed against the µτ values obtained by an independent method based on the voltage–capacitance spectroscopy technique. Furthermore, it is demonstrated that the new method can accurately predict the optimal active layer thickness. [ABSTRACT FROM AUTHOR]

Correction for 'Structure–property relationships of diketopyrrolopyrrole- and thienoacene-based A–D–A type hole transport materials for efficient perovskite solar cells' by Gururaj P. Kini et al., New J. Chem., 2022, DOI: https://doi.org/10.1039/d2nj00294a. [ABSTRACT FROM AUTHOR]

• Polymer donors are suitable for semi-transparent organic solar cells. • PL1 and PL2 can selectively absorb the light in NIR region. • The difference of steric structure of PL1 and PL2 affects device parameters. • PL2-based semi-transparent device presents 40.4% of AVT and 4.00% of LUE. Semi-transparent organic solar cells (ST-OSCs) have attracted significant attention for various applications such as building-integrated photovoltaics and smart window technologies. Although various low-band gap non-fullerene acceptors have been developed, near-infrared (NIR) absorbing polymeric donors have been rarely reported for highly efficient ST-OSCs. In this study, we synthesize cyclopentadithiophene (CPDT) core-based NIR-absorbing polymer donors, PL1 and PL2. These polymer donors show strong NIR absorption capabilities with high transmittance in visible wavelength region and deep-lying HOMO levels for cascade energy level alignment with low-bandgap non-fullerene acceptors. The opaque device with PL2 and PCBM exhibits higher power conversion efficiency of 11.62% than that of the device with PL1 (PCE: 7.54%) due to lower charge-carrier recombination loss and balanced charge-carrier mobilities. Most significantly, incorporation of PL2 into ST-OSCs results in a PCE of 9.91 %, average visible transmittance of 40.4 % and light utilization efficiency (LUE) of 4.00 %. This work achieves the one of the highest LUE in ST-OSCs based on new NIR-absorbing polymer donors. [ABSTRACT FROM AUTHOR]