Sequentially processed quaternary blends for high-performance indoor organic photovoltaic applications

[Display omitted] •Sequential spin coating is used to produce quaternary organic photovoltaics (OPVs).•The sequential process improves molecular properties of blend components.•Sequential OPVs show high performance under diverse indoor irradiation conditions.•The sequential deposition method eliminates compositional optimization procedures.•Sequential deposition can be a platform for developing versatile indoor OPVs. Multicomponent blends, such as quaternary bulk heterojunctions (BHJs), promise high-performance indoor organic photovoltaics (OPVs) with composition-dependent optoelectronic and morphological properties. However, an elaborate optimization of numerous parameters for solution processing and molecular control remains quite challenging. Herein, sequential deposition is demonstrated as a method for the facile fabrication of modified quaternary BHJ layers for high-performance indoor OPV applications. Without any optimization and treatment steps, a simple consecutive spin-coating of two binary donor:acceptor blend solutions produced quaternary BHJ films showing effective absorption at visible-light wavelengths with no significant compromise in the spectral response of components. In addition, the improved photon collection was accompanied by an alleviated hole trap-state density and charge recombination loss, which resulted from the improved molecular ordering and orientation of the polymers. Thus, the sequentially processed OPVs exhibited superior photovoltaic operation under diverse low-intensity indoor irradiation environments. Sequential deposition can serve as a platform to achieve high-performance multicomponent BHJ OPVs for emerging indoor applications, while overcoming the technical and economic shortcomings of conventional multicomponent BHJ OPVs.