2D photonic crystal nanodisk array as electron transport layer for highly efficient perovskite solar cells. (February 2019)

• Record Type: Journal Article
• Authors: Choi, Dong Ho; Nam, Seong Kyung; Jung, Kinam; Moon, Jun Hyuk
• Is Part Of: Nano energy. Volume 56(2019)
• Page Start: 365
• Page End: 372
• Publication Date: 2019-02
• Subjects: 2D photonic crystals -- Electron transport layer -- Perovskite solar cells -- Nanodisk array -- Optical confinement -- Forward scattering; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2018.11.050
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: Perovskite solar cells (PSCs) are currently exhibiting reproducible high efficiency; the manufacturing of low cost, scalable electron transport layers (ETLs) is becoming increasingly important. However, this remains a challenge for electron transport layers that exhibit excellent optical/electrical properties while being a thin film of simple morphology. Here we demonstrate the PSC of a 2D photonic crystal nanodisk (ND) array ETL that is compact, but greatly enhances light harvesting. The ND array is fabricated by nanosphere lithography using a monolayer of self-assembled polymer spheres as a physical mask. We fabricate ND arrays of various lattice constants simply by controlling the size of the polymer spheres. Optimal ND arrays exhibit strong forward scattering and optical confinement effects, greatly improving light harvesting in the perovskite layer. We also observe that the ND array improves charge transport by reducing contact resistance with the perovskite layer. ND array ETL PSCs reach 19% maximum power conversion efficiency, with low photocurrent-voltage hysteresis and stable photocurrent output. Graphical abstract: We demonstrate a perovskite solar cell with a 2D photonic crystal as an electron transport layer and achieve a power conversion efficiency of up to 19% by the effect of improving light harvesting by photonic crystals. Highlights: We introduce TiO2 electron-transport layer with a thin-film 2D photonic crystal structure. We present the surface relief pattern electron-transport layer of a TiO2 nanodisk array fabricated using nanosphere lithography. 2D nanodisk perovskite solar cells achieve a maximum power conversion efficiency of 18.7%. The nanodisk perovskite solar cells also showed low hysteresis in power conversion efficiency and stable efficiency output.