Effects of Self‐Assembled Monolayer Modification of Nickel Oxide Nanoparticles Layer on the Performance and Application of Inverted Perovskite Solar Cells. Issue 19 (25th September 2017)

• Record Type: Journal Article
• Authors: Wang, Qin; Chueh, Chu‐Chen; Zhao, Ting; Cheng, Jiaqi; Eslamian, Morteza; Choy, Wallace C. H.; Jen, Alex K.‐Y.
• Is Part Of: ChemSusChem. Volume 10:Issue 19(2017)
• Page Start: 3794
• Page End: 3803
• Publication Date: 2017-09-25
• Subjects: band bending -- energy level alignment -- flexible perovskite solar cell -- interfacial engineering -- self-assembled monolayer; Green chemistry -- Periodicals; Sustainable engineering -- Periodicals; Chemistry -- Periodicals; Chemical engineering -- Periodicals; 660
• DOI: 10.1002/cssc.201701262
• Languages: English
• ISSNs: 1864-5631

Abstract

Abstract: Entirely low‐temperature solution‐processed (≤100 °C) planar p‐i‐n perovskite solar cells (PSCs) offer great potential for commercialization of roll‐to‐roll fabricated photovoltaic devices. However, the stable inorganic hole‐transporting layer (HTL) in PSCs is usually processed at high temperature (200–500 °C), which is far beyond the tolerant temperature (≤150 °C) of roll‐to‐roll fabrication. In this context, inorganic NiO x nanoparticles (NPs) are an excellent candidate to serve as the HTL in PSCs, owing to their excellent solution processability at room temperature. However, the low‐temperature processing condition is usually accompanied with defect formation, which deteriorates the film quality and device efficiency to a large extent. To suppress this setback, we used a series of benzoic acid selfassembled monolayers (SAMs) to passivate the surface defects of the NiO x NPs and found that 4‐bromobenzoic acid could effectively play the role of the surface passivation. This SAM layer reduces the trap‐assisted recombination, minimizes the energy offset between the NiO x NPs and perovskite, and changes the HTL surface wettability, thus enhancing the perovskite crystallization, resulting in more stable PSCs with enhanced power conversion efficiency (PCE) of 18.4 %, exceeding the control device PCE (15.5 %). Also, we incorporated the above‐mentioned SAMs into flexible PSCs (F‐PSCs) and achieved one of the highest PCE of 16.2 % on a polyethylene terephthalate (PET) substrate with a remarkable power‐per‐weight of 26.9 W g −1 . This facile interfacial engineering method offers great potential for the large‐scale manufacturing and commercialization of PSCs. Abstract : Engineered layers : Low‐temperature solution‐processed NiO x nanoparticle film is usually accompanied with defect formation. Here, we find that 4‐bromobenzoic acid can form a self‐assembled monolayer (SAM) on the NiO x film and effectively tune the interfacial properties, resulting in high perovskite solar cells (PSCs) efficiency. Also, we incorporate the above‐mentioned SAM into flexible PSCs