Tailoring Mixed-Halide, Wide-Gap Perovskites via Multistep Conversion Process

• Published in: ACS applied materials & interfaces Vol. 8; no. 23; pp. 14301 - 14306
• Main Authors: Bae, Dowon, Palmstrom, Axel, Roelofs, Katherine, Mei, Bastian, Chorkendorff, Ib, Bent, Stacey F, Vesborg, Peter C.K
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 15.06.2016; American Chemical Society (ACS)
• Subjects: lead-halide; MATERIALS SCIENCE; multistep deposition; organic−inorganic hybrids; photovoltaics; spin-coating; lead-halide; multistep deposition; organic−inorganic hybrids; photovoltaics; spin-coating
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.6b01246

Wide-band-gap mixed-halide CH3NH3PbI3–X Br X -based solar cells have been prepared by means of a sequential spin-coating process. The spin-rate for PbI2 as well as its repetitive deposition are important in determining the cross-sectional shape and surface morphology of perovskite, and, consequently, J–V performance. A perovskite solar cell converted from PbI2 with a dense bottom layer and porous top layer achieved higher device performance than those of analogue cells with a dense PbI2 top layer. This work demonstrates a facile way to control PbI2 film configuration and morphology simply by modification of spin-coating parameters without any additional chemical or thermal post-treatment.