Longitudinal Through-Hole Architecture for Efficient and Thickness-Insensitive Semitransparent Organic Solar Cells.

Semi-transparent organic solar cells (ST-OSCs) have great potential for application in vehicle- or building-integrated solar energy harvesting. However, ST-OSCs have a trade-off between their efficiency (PCE) and average visible transmittance (AVT). Ultrathin active layers and electrodes are typically utilized to guarantee high PCE and high AVT simultaneously; however, such ultrathin parts are unsuitable for industrial high-throughput manufacturing. In this study, we fabricated ST-OSCs using a longitudinal through-hole architecture to achieve functional region division and to eliminate the dependence on ultrathin films. A complete circuit that vertically corresponds to the silver grid is responsible for obtaining high PCE, and the longitudinal through-holes embedded in it allow most of the light to pass through, thus maximizing the AVT, where the overall transparency is associated with the through-hole specification rather than the thicknesses of the active layer and electrode. Excellent photovoltaic performance over a wide range of transparency (9.80-60.03%), with PCEs ranging from 6.04% to 15.34% is achieved for large-area ST-OSCs. More critically, this architecture allows printable 300-nm-thick devices to achieve a light utilization efficiency (LUE) of 3.25%, which is the highest recorded value thus far, and enables flexible ST-OSCs to exhibit better flexural endurance by dispersing the extrusion stress into the through-holes. This study should pave the way for the fabrication of high-performance ST-OSCs and shows great promise for the commercialization of organic photovoltaics. This article is protected by copyright. All rights reserved.