Copolymer‐Templated Nickel Oxide for High‐Efficiency Mesoscopic Perovskite Solar Cells in Inverted Architecture. (10th June 2021)

• Record Type: Journal Article
• Authors: Sadegh, Faranak; Akin, Seckin; Moghadam, Majid; Keshavarzi, Reza; Mirkhani, Valiollah; Ruiz‐Preciado, Marco A.; Akman, Erdi; Zhang, Hong; Amini, Mina; Tangestaninejad, Shahram; Mohammadpoor‐Baltork, Iraj; Graetzel, Michael; Hagfeldt, Anders; Tress, Wolfgang
• Is Part Of: Advanced functional materials. Volume 31:Number 33(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-06-10
• Subjects: hole transport layers -- inverted architecture -- mesoscopic PSCs -- template‐assisted strategy -- triblock copolymers; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.202102237
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: Despite the outstanding role of mesoscopic structures on the efficiency and stability of perovskite solar cells (PSCs) in the regular (n–i–p) architecture, mesoscopic PSCs in inverted (p–i–n) architecture have rarely been reported. Herein, an efficient and stable mesoscopic NiO x (mp‐NiO x ) scaffold formed via a simple and low‐cost triblock copolymer template‐assisted strategy is employed, and this mp‐NiO x film is utilized as a hole transport layer (HTL) in PSCs, for the first time. Promisingly, this approach allows the fabrication of homogenous, crack‐free, and robust 150 nm thick mp‐NiO x HTLs through a facile chemical approach. Such a high‐quality templated mp‐NiO x structure promotes the growth of the perovskite film yielding better surface coverage and enlarged grains. These desired structural and morphological features effectively translate into improved charge extraction, accelerated charge transportation, and suppressed trap‐assisted recombination. Ultimately, a considerable efficiency of 20.2% is achieved with negligible hysteresis which is among the highest efficiencies for mp‐NiO x based inverted PSCs so far. Moreover, mesoscopic devices indicate higher long‐term stability under ambient conditions compared to planar devices. Overall, these results may set new benchmarks in terms of performance for mesoscopic inverted PSCs employing templated mp‐NiO x films as highly efficient, stable, and easy fabricated HTLs. Abstract : This work presents a facile, low‐cost, and upscalable process for depositing a mesoporous NiO x (mp‐NiO x ) layer based on a polymer templating approach by spin‐coating. Herein, this templated mp‐NiO x film is employed as a hole‐transport layer in inverted perovskite solar cells with an outstanding efficiency larger than 20%. The beneficial effects of this mp‐NiO x layer, such as negligible hysteresis and reduced recombination losses are demonstrated.