Single crystal of two-dimensional mixed-halide copper-based perovskites with reversible thermochromism

Two-Dimensional Halide Perovskites: Tuning Electronic Activities of Defects.

Two-dimensional (2D) halide perovskites are emerging as promising candidates for nanoelectronics and optoelectronics. To realize their full potential, it is important to understand the role of those defects that can strongly impact material properties. In contrast to other popular 2D semiconductors (e.g., transition metal dichalcogenides MX2) for which defects typically induce harmful traps, we...

Singe-crystal microplates of two-dimensional organic-inorganic lead halide layered perovskites for optoelectronics

Reversible photo-induced trap formation in mixed-halide hybrid perovskites for photovoltaics.

We report on reversible, light-induced transformations in (CH3NH3)Pb(Br x I1-x )3. Photoluminescence (PL) spectra of these perovskites develop a new, red-shifted peak at 1.68 eV that grows in intensity under constant, 1-sun illumination in less than a minute. This is accompanied by an increase in sub-bandgap absorption at ∼1.7 eV, indicating the formation of luminescent trap states. Light soaki...

Retrograde solubility of formamidinium and methylammonium lead halide perovskites enabling rapid single crystal growth.

Here we show the retrograde solubility of various hybrid perovskites through the correct choice of solvent(s) and report their solubility curves. Retrograde solubility enables to develop inverse temperature crystallization of FAPbX3 (FA = HC(NH2)2(+), X = Br(-)/I(-)). FAPbI3 crystals exhibit a 1.4 eV bandgap--considerably narrower than their polycrystalline counterparts.

One- and Two- Dimensional Copper(I) Halide Based Coordination Polymers with Bridging Pyridazine or Pyrimidine Ligands

Z. Naturforsch. 54 b, 1175-1180 (1999); received June 9, 1999 Copper(I) Halides, Pyridazine, Pyrimidine, Coordination Polymers 1-Dimensional coordination polymers J. [CuX(/i-pydz)] 1 3 (X = Cl, Br, I; pydz = pyrid­ azine) may be prepared by self-assembly in acetonitrile solution at 120 °C (1) or room temper­ ature (2, 3). Individual chains contain (CuX)2 rings and dimeric [Cu(^-pydz) ] 2 substr...