Ordered nanostructured crystals of thin organic–inorganic metal halide perovskites (OIHPs) are of great interest to researchers because of the dimensional-dependence of their photoelectronic properties for developing OIHPs with novel properties. Top-down routes such as nanoimprinting and electron beam lithography are extensively used for nanopatterning OIHPs, while bottom-up approaches are seldom used. Herein, developed is a simple and robust route, involving the controlled crystallization of the OIHPs templated with a self-assembled block copolymer (BCP), for fabricating nanopatterned OIHP films with various shapes and nanodomain sizes. When the precursor solution consisting of methylammonium lead halide (MAPbX3, X = Br−, I−) perovskite and poly(styrene)-block-poly(2-vinylpyridine) (PS-b-P2VP) is spin-coated on the substrate, a nanostructured BCP is developed by microphase separation. Spontaneous crystallization of the precursor ions preferentially coordinated with the P2VP domains yields ordered nanocrystals with various nanostructures (cylinders, lamellae, and cylindrical mesh) with controlled domain size (≈40–72 nm). The nanopatterned OIHPs show significantly enhanced photoluminescence (PL) with high resistance to both humidity and heat due to geometrically confining OIHPs in and passivation with the P2VP chains. The self-assembled OIHP films with high PL performance provide a facile control of color coordinates by color conversion layers in blue-emitting devices for cool-white emission.
Bibliographical noteFunding Information:
H.H. and B.J. contributed equally to this work. This research was supported by the Creative Materials Discovery Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (2018M3D1A1058536). This research was also supported by a grant from the National Research Foundation of Korea (NRF) funded by the Korean government (MEST) (nos. 2017R1A2A1A05001160 and 2016M3A7B4910530). This work is based on a work supported by the Ministry of Trade, Industry & Energy (MOTIE, Korea) under the Industrial Technology Innovation Program (no. 10063274).
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All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics