Highly Stable Tetrahydrothiophene 1-Oxide Caged Copper Bromide and Chloride Clusters with Deep-Red to Near-IR Emission

Abstract

All-inorganic copper­(I)-based metal halides have emerged as promising candidates for the replacement of lead perovskites because of their outstanding optical properties. However, the limited structure tunability prohibits their further exploration of properties including red photoluminescence (PL). Here, we report a series of red-emissive lead-free hybrid organic–inorganic copper halides A6(C4H8OS)12[Cu8X13]­[Cu4X4(OH)­(H2O)] (ACX-THTO, A = K, Rb, and Cs; X = Cl, Br; THTO = C4H8OS) with the highest photoluminescence quantum yield (PLQY) of 42%. These compounds possess similar crystal structures, and their emission can be tuned in the spectral range of 676–732 nm by controlling their compositions. Additionally, by removing and adding THTO, the reversible transformation between CsCu2Br3 featuring one-dimensional (1D) chains and Cs6(C4H8OS)12[Cu8Br13]­[Cu4Br4(OH)­(H2O)] (CCB-THTO) with zero-dimensional (0D) clusters can be realized. We also demonstrate that the incorporation of THTO in the crystal structures instead of dimethyl sulfoxide (DMSO) can significantly enhance the stability and PL of compounds with the same inorganic components.

Organic–Inorganic Hybrid Alkali Copper Iodides for Bright Emission across the Visible Spectrum

“…The five iodines and one water are disordered throughout the six positions of the Cu 4 unit and edge-bridge the tetrahedra, and the ratio of iodine to water in the copper− iodine cluster is determined among the various I/O ratios with the lowest R 1 error values (the agreement between the calculated and observed models) obtained by I/O = 5:1 which is coincidently true for both the K and Rb analogues (Table S4), which is different from the best R 1 value for Br/O = 4:2 of the reported [Cu 4 Br 4 (OH)(H 2 O)] − analogue. 9,24 1c and S4). One reason for their different structure is the distinct steric hindrance, shape, and size of used solvents, which are also reported for Cu m I m+n (L) n and copper bromide hybrids.…”

“…The five iodines and one water are disordered throughout the six positions of the Cu 4 unit and edge-bridge the tetrahedra, and the ratio of iodine to water in the copper− iodine cluster is determined among the various I/O ratios with the lowest R 1 error values (the agreement between the calculated and observed models) obtained by I/O = 5:1 which is coincidently true for both the K and Rb analogues (Table S4), which is different from the best R 1 value for Br/O = 4:2 of the reported [Cu 4 Br 4 (OH)(H 2 O)] − analogue. 9,24 The alkali elements, potassiums or rubidiums, cap the faces formed by the 4 neighboring iodines and 12 outermost iodines of [Cu 8 I 13 ] 5− ; then, the crystal array is formed by the bridging of the μ 2 -oxygens of four DMSO molecules between two capped potassiums (or rubidiums) from neighboring clusters. The clusters of [Cu 4 I 5 (H 2 O)] − sit in the cavities of the array.…”

High-temperature negative thermal quenching phosphors from molecular-based materials

“…[19][20][21][22][23][24][25] However, most copper-halide clusters suffer from the TQ effect of PL, and the synthesis of copper-halide cluster-based materials as unconventional phosphors that exhibit the NTQ effect is highly challenging. [26][27][28][29][30][31][32][33][34][35][36] By virtue of the delocalization-to-localization transition in imidazole-based ligands, we recently developed imidazole-copper(I) coordination networks to demonstrate the abnormal NTQ effect of their PL emission spectra below RT. 37,38 In this work, we continue to employ a prototype copper-iodide cubic cluster as a building block for the preparation of cluster-based coordination polymers (CPs) using bis-imidazole terminal ligands as the linker (ESI, † Fig.…”

“…19–25 However, most copper–halide clusters suffer from the TQ effect of PL, and the synthesis of copper–halide cluster-based materials as unconventional phosphors that exhibit the NTQ effect is highly challenging. 26–36…”