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Highly Efficient and Environmentally Stable Flexible Color Converters Based on Confined CH3NH3PbBr3 Nanocrystals
journal contribution
posted on 2018-10-12, 00:00 authored by Andrea Rubino, Miguel Anaya, Juan F. Galisteo-López, T. Cristina Rojas, Mauricio E. Calvo, Hernán MíguezIn this work, we
demonstrate a synthetic route to attain methylammonium
lead bromide (CH3NH3PbBr3) perovskite
nanocrystals (nc-MAPbBr3, 1.5 nm < size < 3 nm) and
provide them with functionality as highly efficient flexible, transparent,
environmentally stable, and adaptable color-converting films. We use
nanoparticle metal oxide (MOx) thin films as porous scaffolds of controlled
nanopores size distribution to synthesize nc-MAPbBr3 through
the infiltration of perovskite liquid precursors. We find that the
control over the reaction volume imposed by the nanoporous scaffold
gives rise to a strict control of the nanocrystal size, which allows
us to observe well-defined quantum confinement effects on the photo-emission,
being the luminescence maximum tunable with precision between λ
= 530 nm (green) and λ = 490 nm (blue). This hybrid nc-MAPbBr3/MOx structure presents high mechanical stability and permits
subsequent infiltration with an elastomer to achieve a self-standing
flexible film, which not only maintains the photo-emission efficiency
of the nc-MAPbBr3 unaltered but also prevents their environmental
degradation. Applications as adaptable color-converting layers for
light-emitting devices are envisaged and demonstrated.