Halide perovskite nanocrystal arrays: Multiplexed synthesis and size-dependent emission

Abstract

Halide perovskites have exceptional optoelectronic properties, but a poor understanding of the relationship between crystal dimensions, composition, and properties limits their use in integrated devices. We report a new multiplexed cantilever-free scanning probe method for synthesizing compositionally diverse and size-controlled halide perovskite nanocrystals spanning square centimeter areas. Single-particle photoluminescence studies reveal multiple independent emission modes due to defect-defined band edges with relative intensities that depend on crystal size at a fixed composition. Smaller particles, but ones with dimensions that exceed the quantum confinement regime, exhibit blue-shifted emission due to reabsorption of higher-energy modes. Six different halide perovskites have been synthesized, including a layered Ruddlesden-Popper phase, and the method has been used to prepare functional solar cells based on single nanocrystals. The ability to pattern arrays of multicolor light-emitting nanocrystals opens avenues toward the development of optoelectronic devices, including optical displays.

High‐Resolution Patterned Functionalization of Slippery “Liquid‐Like” Brush Surfaces via Microdroplet‐Confined Growth of Multifunctional Polydopamine Arrays

“…The crystallization process was highly relevant to the surface roughness, interfacial interactions, as well as solution properties. [ 69 ] We showed that when PDA templates with a smaller size (≈10 µm) and smooth surface ( R q < 20 nm) were employed, the perovskite microcrystals could become larger (>4 µm size), with less crystals covering each microdot (Figure 6F and Figure S8C, Supporting Information). Besides, the MA 3 Bi 2 Br 9 QDs were also successfully patterned through dewetting of the non‐polar toluene solution, although only a small amount of solution was observed to leave on the PDA surface (Figure 6G).…”

Dip‐Pen Nanolithography Enabled Functional Nanomaterials and Their Applications

“…Reproduced with permission. [ 37 ] Copyright 2020, American Association for the Advancement of Science.…”

“…By further designing appropriate inks, single‐crystal halide perovskite nanoarrays were patterned over a large‐area (square centimeter) via PPL with great control over composition and size (Figure 5 2020‐2). [ 37 ] Unlike molecular or polymer inks used in conventional PPL, a liquid organic ink containing halide perovskite precursors dissolved in a mixture of dimethyl sulfoxide (DMSO) and sulfolane was used and applied to the array of PDMS pyramidal pens. Due to high surface tension and low viscosity, the ink accumulates around the base of each pyramid and serves as a reservoir for continuous inking as subsequent features are deposited.…”

“…Early studies of DPN focused on direct molecular transport, such as 1‐octadecanethiol (ODT), [ 10,15 ] 16‐mercaptohexadecanoic acid (MHA), [ 15 ] DNA, [ 16–17 ] and proteins. [ 18–21 ] Subsequently, with the assistance of chemical etching, [ 22–26 ] assembly, [ 27–31 ] micro‐ or nanoreactor construction, [ 32–37 ] and block copolymers, [ 11,38–45 ] the utility of DPN has been expanded to include the fabrication of a large variety of NMs and integrated NM systems. The as‐resulted materials have shown great potential to influence a wide range of fields.…”

Dual‐Protected Metal Halide Perovskite Nanosheets with an Enhanced Set of Stabilities

“…To date, all‐inorganic perovskite nanocrystals (PNCs) of diverse shapes (e.g., nanocubes, [11] nanowires (NWs), [12] nanosheets (NSs) [13] and heterostructures [9, 14] ), synthesized by several impressive synthetic routes (e.g., ligand‐assisted reprecipitation (LARP), [15] post‐treatment, [16] confined growth in inorganic matrix, [11c] etc. ), have emerged as building blocks for constructing PNC‐based optoelectronic devices [17, 18] . The stability of PNCs against external stimuli (e.g., water, polar solvents, light) is the key to their utility for practical applications.…”