Stable Organic Solar Cells Enabled by Simultaneous Hole and Electron Interlayer Engineering

The development of high-performance organic solar cells(OSCs)with high operational stability is essential to accelerate their commercialization.Unfortunately,our understanding of the origin of instabilities in state-of-the-art OSCs based on bulk heterojunction(BHJ)featuring non-fullerene acceptors(NFAs)remains limited.Herein,we developed NFA-based OSCs using different charge extraction interlayer materials and studied their storage,thermal,and operational stabilities.Despite the high power conversion efficiency(PCE)of the OSCs(17.54%),we found that cells featuring self-assembled monolayers(SAMs)as hole-extraction interlayers exhibited poor stability.The time required for these OSCs to reach 80%of their initial performance(T_(80))was only 6h under continuous thermal stress at 85℃in a nitrogen atmosphere and 1 h under maximum power point tracking(MPPT)in a vacuum.Inserting MoO_(x)between ITO and SAM enhanced the T_(80)to 50 and~15 h after the thermal and operational stability tests,respectively,while maintaining a PCE of 16.9%.Replacing the organic PDINN electron transport layer with ZnO NPs further enhances the cells'thermal and operational stability,boosting the T_(80)to 1000 and 170 h,respectively.Our work reveals the synergistic roles of charge-selective interlayers and device architecture in developing efficient and stable OSCs.

Large-area plastic nanogap electronics enabled by adhesion lithography

Large-area manufacturing of flexible nanoscale electronics has long been sought by the printed electronics industry.However,the lack of a robust,reliable,high throughput and low-cost technique that is capable of delivering high-performance functional devices has hitherto hindered commercial exploitation.Herein we report on the extensive range of capabilities presented by adhesion lithography(a-Lith),an innovative patterning technique for the fabrication of coplanar nanogap electrodes with arbitrarily large aspect ratio.We use this technique to fabricate a plethora of nanoscale electronic devices based on symmetric and asymmetric coplanar electrodes separated by a nanogap<15 nm.We show that functional devices including self-aligned-gate transistors,radio frequency diodes and rectifying circuits,multi-colour organic light-emitting nanodiodes and multilevel non-volatile memory devices,can be fabricated in a facile manner with minimum process complexity on a range of substrates.The compatibility of the formed nanogap electrodes with a wide range of solution processable semiconductors and substrate materials renders a-Lith highly attractive for the manufacturing of large-area nanoscale opto/electronics on arbitrary size and shape substrates.