Enhancing the Energy‐Conversion Efficiency of Solid‐State Dye‐Sensitized Solar Cells with a Charge‐Transfer Complex based on 2,3‐Dichloro‐5,6‐dicyano‐1,4‐benzoquinone

Abstract

AbstractAs a champion hole‐transporting material (HTM), 2,2′7,7′‐tetrakis‐(N,N‐di‐p‐methoxyphenylamine)‐9,9′‐spirobifluorene (Spiro‐OMeTAD) has been widely used in solid‐state dye‐sensitized solar cells (ssDSCs). Owing to the low conductivity of Spiro‐OMeTAD, a chemical doping strategy is commonly used to enhance its hole‐transporting properties. In this study, we report a strong electron acceptor, 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (DDQ) as an additive for Spiro‐OMeTAD along with its application in ssDSCs. We show that the conductivity of Spiro‐OMeTAD increases from 5.31×10−5 to 2.22×10−4 S cm upon the addition of 0.04 % DDQ, and the power conversion efficiency (PCE) of the ssDSCs also increases. By utilizing a donor–π–acceptor sensitizer with a high coefficient and an HTM with an optimized doping ratio, we were able to achieve a high PCE of 6.37 % for the ssDSCs under 100 mW cm−2 AM1.5G simulated illumination, in comparison to the PCE of the pristine device, which was only 3.50 %. An increase in the application of benzoquinone‐based materials for organic electronics is expected, especially for solar‐cell applications.