Cold Isostatic‐Pressured Silver Nanowire Electrodes for Flexible Organic Solar Cells via Room‐Temperature Processes

Abstract

Transparent conducting electrodes (TCEs) are considered to be an essential structural component of flexible organic solar cells (FOSCs). Silver nanowire (AgNW) electrodes are widely used as TCEs owing to their excellent electrical and optical properties. The fabrication of AgNW electrodes has faced challenges in terms of forming large uniform interconnected networks so that high conductivity and reproducibility can be achieved. In this study, a simple method for creating an intimate contact between AgNWs that uses cold isostatic pressing (CIP) is demonstrated. This method increases the conductivity of the AgNW electrodes, which enables the fabrication of high-efficiency inverted FOSCs that have a power conversion efficiency of 8.75% on flexible polyethylene terephthalate with no short circuiting occurring as the CIP process minimizes the surface roughness of the AgNW electrode. This allows to achieve 100% manufacturing yield of FOSCs. Furthermore, these highly efficient FOSCs are proven to only be 2.4% less efficient even for an extreme bending radius of R ≈ 1.5 mm, compared with initial efficiency.

Flexible and Semitransparent Organic Solar Cells

“…Moreover, the efficiency of the bendable devices fabricated with the Ag NWs/PET BTE only decreased slightly to ≈96% of its initial value even after the devices were bent for 1000 times with a radius of ≈1.5 mm. More recently, Seo et al [29] developed a simple cold isostatic pressing (CIP) method that enabled intimate contact between AgNWs, leading to a reduced sheet resistance of 20.7 Ω sq −1 . Flexible OSCs based on PTB7-Th:PC 71 BM with the CIP AgNWs BTE exhibit a PCE of 8.75%.…”

Highly Efficient Semitransparent Organic Solar Cells with Color Rendering Index Approaching 100

“…Even worse, these ST‐OSCs generally display various colors, making it more difficult to realize high‐performance ST‐OSCs with promising AVT and neutral color simultaneously. To address the above issues, many efforts have been devoted to the following aspects: (1) developing high‐conductivity and high‐transparency electrodes to reduce the visible‐light reflectance/absorption and contact resistance; (2) synthesizing a nonfullerene acceptor‐based photoactive layer with low energy losses and strong near‐infrared (NIR) absorption but weak visible absorption to simultaneously increase AVT and power conversion efficiency (PCE); and (3) incorporating optical engineering to enhance absorption and tuning color conception . Based on the above strategies, as shown in Figure a, ST‐OSCs with promising PCEs of 8%–10% and AVT of over 20% were successfully constructed .…”

Organic Flexible Electronics

“…With the modified electrode, flexible OPVs based on photoactive layer of PTB7‐F20:PC 71 BM showed a high PCE of 5.02% . Moreover, Seo et al presented a novel cold isostatic pressing technique at room temperature to prepare transparent Ag NW electrodes that showed outstanding electrical and optical properties. As shown in Figure a,b, the flexible OPVs based on PTB7‐Th:PC 71 BM with the novel Ag NW electrode exhibit a PCE of 8.94% on glass and 8.75% on a PET substrate.…”