Ligand Control of Structural Diversity in Luminescent Hybrid Copper(I) Iodides

Abstract

Copper (I) iodide hybrids are of interest for next-generation lighting technologies because of their efficient luminescence in the absence of rare-earths. Here, we report ten structurally diverse hybrid copper (I) iodides that emit in the green-red region with quantum yields reaching 67 %. The compounds display a diversity of structures including ones with 1D Cu-1 chains, Cu2I2 rhomboid dimers, and structures with two different arrangements of Cu4I4 tetramers. The compounds with Cu2I2 rhomboid dimers or Cu4I4 cubane tetramer have higher photoluminescence quantum yield than those with Cu-I 1D chain and octahedral Cu4I4 tetramer, owing to the optimal degree of condensation of the inorganic motifs that suppresses non-radiative processes. Electronic structure calculations on these compounds point out the critical influence of the inorganic motif and organic ligand on the nature of the band gaps and thus the excitation characteristics. Temperature dependent photoluminescence spectra are presented to better understand the nature of luminescence in compounds with different inorganic motifs. The emerging understanding of composition-structure-property correlations in this family provide inspiration for the rational design of hybrid phosphors for general lighting applications.

Emission and Luminescent Vapochromism Control of Octahedral Cu4I4 Complexes by Conformationally Restricted P,N Ligands

“…Among various copper(I) structures tetranuclear complexes become promising candidates for the design of “stimuli‐responsive” emitters [27,35] . The tetranuclear complexes are represented by structures with the stair‐step, cubane‐like, and octahedral Cu 4 I 4 metal‐halide cores [36–45] …”

Chiral 2D Cu(I) Halide Frameworks

“…However, deviation exists as the determination of the exact fundamental bandgap for a low dimensional luminescent material is generally hindered by the existence of exciton absorption band, as often reported in literature. 69,70,71 As shown in Figure S12, for (S-PCA)CuBr 2 , the localized orbitals between carboxyl groups give rise to a smaller broadening of the band and a higher energy, resulting in Cu 4s orbitals being the CBM. For (S-PCA)CuBr 2 •0.5H 2 O, the delocalized orbitals between carboxyl groups increase the energy bandwidth and reduce the energy level positions, so the organic molecule contributes to the CBM.…”

Chemical etching strategy to prepare microtubes of a hybrid organic cuprous halide

“…Hybrid organic cuprous halides have efficient luminescence, environmentally-friendly components and fruitful structures. [29][30][31][32][33] In its open ambient state, Cu(I) is prone to disproportionation reactions unless there is a suitable ligand stabilizing the valence of Cu(I). 34,35 For example, hybrid organic cuprous iodide can be synthesized in an ambient environment due to the strong bonding between Cu(I) and I.…”