A low cost azomethine-based hole transporting material for perovskite photovoltaics

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Vol. 3; no. 23; pp. 12159 - 12162
• Main Authors: Petrus, M L, Bein, T, Dingemans, T J, Docampo, P
• Format: Journal Article
• Language: English
• Published: 01.01.2015
• Subjects: Accessibility; Byproducts; Perovskites; Photovoltaic cells; Solar cells; Synthesis (chemistry); Transporter; Transporting
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/c5ta03046c

Most hole transporting materials (HTMs) prepared for perovskite solar cell applications are synthesized viacross-coupling reactions that require expensive transition metal catalysts, inert reaction conditions and extensive product purification; making large-scale production cost-prohibitive. Here, we describe the synthesis of a simple azomethine-based conjugated small-molecule (EDOT-OMeTPA) which is easily prepared in a cost effective Schiff base condensation reaction, with water being the only by-product. As the hole transporter in planar CH sub(3)NH sub(3)PbI sub(3 ) perovskite solar cells, efficiencies exceeding 11% were reached. This result is comparable to state-of-the-art materials such as Spiro-OMeTAD on a like-to-like comparison, while cost estimations show that the material cost is about one order of magnitude lower for EDOT-OMeTPA, resulting in a negligible cost-per-peak-Watt contribution of 0.004 $ W super(-1). In addition, the high synthetic accessibility of EDOT-OMeTPA also reduces the toxic chemical waste and therefore greatly reduces its environmental impact. Our results pave the way towards low-cost, environmentally friendly and efficient HTMs.