Zero-Dimensional Broadband Yellow Light Emitter (TMS)3Cu2I5 for Latent Fingerprint Detection and Solid-State Lighting

Crystal structures and luminescence properties of halocuprates with trimethylsulfonium cations

We report the crystal structures, thermal stability, and luminescence properties of three trimethylsulfonium halocuprates: (TMS)Cu2I3, and two new bromide phases: (TMS)Cu2Br3 and (TMS)2CuBr3. (TMS)Cu2I3 and (TMS)Cu2Br3 are isostructural and contain double chains of edge-sharing [CuX4] tetrahedra, whereas (TMS)2CuBr3 features isolated [CuBr3]2- triangular units. All compounds exhibit direct bandgaps and demonstrate photoluminescence at low temperature, with (TMS)Cu2Br3 demonstrating temperature-dependent dual emission behavior, observed for the first time among related hybrid halocuprates. Through comparative analysis of optical properties with structurally related halocuprates and DFT calculations, we elucidate the structure-property relationships governing the observed luminescence behavior of ACu2X3-type halocuprates.

Supra-Hybrid Nanocarriers of Calix[4]Arene and PLGA for Enhanced Encapsulation and Extended Delivery of Gossypol in Cancer Therapy

In this study, supra-hybrid nanocarriers Cal-P NPs are developed by combining amphiphilic macrocyclic calix[4]arene and PLGA, offering adequate stability and multifunctionality as a single-platform nanocarrier resulting in monodispersed nanoparticles with unique synthetic tunability and an optimized hydrophobic core for therapeutic encapsulation. Unlike conventional multicomponent systems, the design eliminates the need for many external stabilizers while enabling tailored PEGylation for controlled drug release, as demonstrated with hydrophobic gossypol. This innovation addresses key limitations in cancer nanomedicine, including premature drug leakage and dose frequency, through a synthetically tunable and structurally optimized, bioresistant core. Gossypol, a model bioactive molecule with poor water solubility, is effectively loaded into the Cal-P NPs, significantly enhancing its aqueous solubility to millimolar concentrations. The encapsulation is driven by favorable interactions between gossypol and the hydrophobic groups of calixarene and PLGA, resulting in a stable core with sustained release properties. Validated through in vivo pharmacokinetic studies and detailed anticancer experiments in two distinct cancer cell lines, GP-Cal-P NPs demonstrated their potential as a robust platform for therapeutic delivery. These findings emphasize the versatility of Cal-P NPs in addressing challenges associated with hydrophobic drugs and highlight their promise for further preclinical and clinical development.

Reversible Structural Phase Transitions in Zero-Dimensional Cu(I)-Based Metal Halides for Dynamically Tunable Emissions

Exploring structural phase transitions and luminescence mechanisms in zero-dimensional (0D) metal halides poses significant challenges, that are crucial for unlocking the full potential of tunable optical properties and diversifying their functional capabilities. Herein, we have designed two inter-transformable 0D Cu(I)-based metal halides, namely (C19H18P)2CuI3 and (C19H18P)2Cu4I6, through distinct synthesis conditions utilizing identical reactants. Their optical properties and luminescence mechanisms were systematically elucidated by experiments combined with density functional theory calculations. The bright cyan-fluorescent (C19H18P)2CuI3 with high photoluminescence quantum yield (PLQY) of 77 % is attributed to the self-trapped exciton emission. Differently, the broad yellow-orange fluorescence of (C19H18P)2Cu4I6 displays a remarkable PLQY of 83 %. Its luminescence mechanism is mainly attributed to the combined effects of metal/halide-to-ligand charge transfer and cluster-centered charge transfer, which effects stem from the strong Cu-Cu bonding interactions in the (Cu4I6)2- clusters. Moreover, (C19H18P)2CuI3 and (C19H18P)2Cu4I6 exhibit reversible structural phase transitions. The elucidation of the phase transitions mechanism has paved the way for an unforgeable anti-counterfeiting system. This system dynamically shifts between cyan and yellow-orange fluorescence, triggered by the phase transitions, bolstering security and authenticity. This work enriches the luminescence theory of 0D metal halides, offering novel strategies for optical property modulation and fostering optical applications.

Near Ultraviolet-Excitable Cyan-Emissive Hybrid Copper(I) Halides Nonlinear Optical Crystals with Near-Unity Photoluminescence Quantum Yield and High-Efficiency X-ray Scintillation

Designing and synthesizing multifunctional hybrid copper halides with near ultraviolet (NUV) light-excited high-energy emission (<500 nm) remains challenging. Here, a pair of broadband-excited high-energy emitting isomers, namely, α-/β-(MePh3P)2CuI3 (MePh3P=methyltriphenylphosphonium), were synthesized. α-(MePh3P)2CuI3 with blue emission peaking at 475 nm is firstly discovered wherein its structure contains regular [CuI3]2- triangles and crystallizes in centrosymmetric space group P21/c. While β-(MePh3P)2CuI3 featuring distorted [CuI3]2- planar triangles shows inversion symmetry breaking and crystallizes in the noncentrosymmetric space group P21, which exhibits cyan emission peaking at 495 nm with prominent near-unity photoluminescence quantum yield and the excitation band ranging from 200 to 450 nm. Intriguingly, β-(MePh3P)2CuI3 exhibits phase-matchable second-harmonic generation response of 0.54×KDP and a suitable birefringence of 0.06@1064 nm. Furthermore, β-(MePh3P)2CuI3 also can be excited by X-ray radioluminescence with a high scintillation light yield of 16193 photon/MeV and an ultra-low detection limit of 47.97 nGy/s, which is only 0.87 % of the standard medical diagnosis (5.5 μGy/s). This work not only promotes the development of solid-state lighting, laser frequency conversion and X-ray imaging, but also provides a reference for constructing multifunctional hybrid metal halides.

Efficient tunable white emission and multiple reversible photoluminescence switching in organic Tin(IV) chlorides via regulating the host lattice environment of antimony ions for multifunctional applications

The host lattice environments of Sb3+ has a great influence on its photophysical properties. Here, we synthesized three zero-dimensional organic metal halides of (TPA)2SbCl5 (1), Sb3+-doped (TPA)SnCl5(H2O)·2H2O (Sb3+-2), and Sb3+-doped (TPA)2SnCl6 (Sb3+-3). Compared with the intense orange emission of 1, Sb3+-3 has smaller lattice distortion, thus effectively suppressing the exciton transformation from singlet to triplet self-trapped exciton (STE) states, which makes Sb3+-3 has stronger singlet STE emission and further bring a white emission with a photoluminescence quantum efficiency (PLQE) of 93.4%. Conversely, the non-emission can be observed in Sb3+-2 even though it has a similar [SbCl5]2- structure to 1, which should be due to its indirect bandgap characteristics and the effective non-radiative relaxation caused by H2O in the lattice. Interestingly, the non-emission of Sb3+-2 can convert into the bright emission of Sb3+-3 under TPACl DMF solution treatment. Meanwhile, the white emission under 315 nm excitation of Sb3+-3 can change into orange emission upon 365 nm irradiation, and the luminescence can be further quenched by the treatment of HCl. Therefore, a triple-mode reversible luminescence switch of off-onI-onII-off can be achieved. Finally, we demonstrated the applications of Sb3+-doped compounds in single-component white light illumination, latent fingerprint detection, fluorescent anti-counterfeiting, and information encryption.

Structural and Physical Properties of Two Distinct 2D Lead Halides with Intercalated Cu(II)

Transition metal cation intercalation between the layers of two-dimensional (2D) metal halides is an underexplored research area. In this work we focus on the synthesis and physical property characterizations of two layered hybrid lead halides: a new compound [Cu(O2C-CH2-NH2)2]Pb2Br4 and the previously reported [Cu(O2C-(CH2)3-NH3)2]PbBr4. These compounds exhibit 2D layered crystal structures with incorporated Cu2+ between the metal halide layers, which is achieved by combining Cu(II) and lead bromide with suitable amino acid precursors. The resultant [Cu(O2C-(CH2)3-NH3)2]PbBr4 adopts a 2D layered perovskite structure, whereas the new compound [Cu(O2C-CH2-NH2)2]Pb2Br4 crystallizes with a new structure type based on edge-sharing dodecahedral PbBr5O3 building blocks. [Cu(O2C-CH2-NH2)2]Pb2Br4 is a semiconductor with a bandgap of 3.25 eV. It shows anisotropic charge transport properties with a semiconductor resistivity of 1.44×1010 Ω·cm (measured along the a-axis) and 2.17×1010 Ω·cm (along the bc-plane), respectively. The fabricated prototype detector based on this material showed response to soft low-energy X-rays at 8 keV with a detector sensitivity of 1462.7 μCGy-1cm-2, indicating its potential application for ionizing radiation detection. These encouraging results are discussed together with the results from density functional theory calculations, optical, magnetic, and thermal property characterization experiments.

Ultra-Broad-Band-Excitable Cu-Based Halide (C4H10N)4Cu4I8 with High Stability for LED Applications

Currently, organic-inorganic hybrid cuprous-based halides are receiving substantial attention for their eco-friendliness, distinctive structures, and outstanding photophysical properties. Nevertheless, most of the reported cuprous-based halides demand deep ultraviolet excitation with a narrow excitation range that can meet the commercial requirement. Herein, zero-dimensional (0D) cuprous-based halide (C4H10N)4Cu4I8 single crystals (SCs) were synthesized, with an ultrabroad band excitation ranging 260-450 nm and a greenish-yellow emission band peaking at 560 nm. Excitingly, (C4H10N)4Cu4I8 also features a large Stokes shift of 300 nm, a high photoluminescence quantum yield (PLQY) of up to 84.66%, and a long lifetime of 137 μs. Furthermore, density functional theory calculations were performed to explore the relationship between structure and photophysical properties, and the photoluminescence performance of (C4H10N)4Cu4I8 originates from the electron interactions in [Cu2I4]2- clusters. Taking advantage of broad band excitation and excellent photoluminescent performances, a high luminescence characteristic UV-pumped light-emitting diode (LED) device with remarkable color stability was fabricated by employing the as-synthesized (C4H10N)4Cu4I8 SCs, which present the promising applications of low-dimensional cuprous-based halides in solid-state lighting.

Synthesis and Characterization of New Hybrid Organic-Inorganic Metal Halides [(CH3)3SO]M2I3 (M = Cu and Ag)

Recently, all-inorganic copper(I) metal halides have emerged as promising optical materials due to their high light emission efficiencies. This work details the crystal structure of the two hybrid organic-inorganic metal halides [(CH3)3SO]M2I3 (M = Cu and Ag) and their alloyed derivatives [(CH3)3SO]Cu2-xAgxI3 (x = 0.2; 1.25), which were obtained by incorporating trimethylsulfoxonium organic cation (CH3)3SO+ in place of Cs+ in the yellow-emitting all-inorganic CsCu2I3. These compounds are isostructural and centrosymmetric with the space group Pnma, featuring one-dimensional edge-sharing [M2I3]- anionic double chains separated by rows of (CH3)3SO+ cations. Based on density functional theory calculations, the highest occupied molecular orbitals (HOMOs) of [(CH3)3SO]M2I3 (M = Cu and Ag) are dominated by the Cu or Ag d and I p orbitals, while the lowest unoccupied molecular orbitals (LUMOs) are Cu or Ag s and I p orbitals. [(CH3)3SO]Cu2I3 single crystals exhibit a semiconductor resistivity of 9.94 × 109 Ω·cm. Furthermore, a prototype [(CH3)3SO]Cu2I3 single-crystal-based X-ray detector with a detection sensitivity of 200.54 uCGy-1 cm-2 (at electrical field E = 41.67 V/mm) was fabricated, indicating the potential use of [(CH3)3SO]Cu2I3 for radiation detection applications.