Light-emission organic solar cells with MoO₃:Al interfacial layer–preparation and characterizations

Abstract

A light-emitting organic solar cell (LE-OSC) with electroluminescence (EL) and photovoltaic (PV) properties is successfully fabricated by connecting the EL and PV units using a MoO₃:Al co-evaporation interfacial layer, which has suitable work function and good transmittance. PV and EL units are fabricated based on poly(3-hexylthiophene) (P3HT)-indene-C₆₀ bisadduct (IC₆₀BA) blends, and 4,4′-bis (N-carbazolyl) biphenyl-fac-tris (2-phenylpyridine) iridium (Ir(ppy)₃), respectively. The work function and the transmittance of the MoO₃:Al co-evaporation are measured and adjusted by the ultraviolet photoelectron spectroscopy and the optical spectrophotometer to obtain the better bi-functional device performance. The forward- and reverse-biased current density-voltage characteristics in dark and under illumination are evaluated to better understand the operational mechanism of the LE-OSCs. A maximum luminance of 1550 cd/m² under forward bias and a power conversion efficiency of 0.24% under illumination (100 mW/cm²) are achieved in optimized LE-OSCs. The proposed device structure is expected to provide valuable information in the film conditions for understanding the polymer blends internal conditions and meliorating the film qualities.

Graphical abstract

Keywords

organic solar cell (OSC) / polymer-fullerene / light emission / MoO₃:Al interfacial layer

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Acknowledgements

The authors acknowledge financial support from the National Natural Science Foundation of China (Grant No. 61674109), Jiangsu Province College Student Innovation and Entrepreneurship Training Program (No. 202010285087Y), and the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (No. 19KJD510006). This project is also funded by the Collaborative Innovation Center of Suzhou Nano Science and Technology, and by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD).

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