Utilizing the unique charge extraction properties of antimony tin oxide nanoparticles for efficient and stable organic photovoltaics
Chao Liu, Roberto Félix, Karen Forberich, Xiaoyan Du, Thomas Heumüller, Gebhard J. Matt, Ening Gu, Jonas Wortmann, Yicheng Zhao, Yuanyuan Cao, Yakun He, Lei Ying, Alina Hauser, Marek Oszajca, Benjamin Hartmeier, Michaël Rossier, Norman A. Lüchinger, Yi‐Sheng Liu, Jinghua Guo, Kaiqi Nie, Regan G. Wilks, Julien Bachmann, Marcus Bär, Ning Li, Christoph J. Brabec
Abstract
Simultaneously enhancing device performance and longevity, as well as balancing the requirements on cost, scalability, and simplification of processing, is the goal of interface engineering of organic solar cells (OSCs). In our work, we strategically introduce antimony (Sb 3+ ) cations into an efficient and generic n-type SnO 2 nanoparticles (NPs) host during the scalable flame spray pyrolysis synthesis. Accordingly, a significant switch of conduction property from an n-type character to a p-type character is observed, with a corresponding shift in the work function (WF) from 4.01 ± 0.02 eV for pristine SnO 2 NPs to 5.28 ± 0.02 eV for SnO 2 NPs with 20 mol. % Sb content (ATO). Both pristine SnO 2 and ATO NPs with fine-tuned optoelectronic properties exhibit remarkable charge carrier extraction properties, excellent UV resistance and photo-stability being compatible with various state-of-the-art OSCs systems. The reliable and scalable pristine SnO 2 and ATO NPs processed by doctor-blading in air demand no complex post-treatment. Our work offers a simple but unique approach to accelerate the development of advanced interfacial materials, which could circumvent the major existing interfacial problems in solution-processed OSCs.