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With the rapid development of white LEDs, the research of new and efficient white light emitting materials has attracted increasing attention. Zero dimensional (0D) organic-inorganic hybrid metal halide perovskites with superior luminescent property are promising candidates for LED application, due to their abundant and tailorable structure. Herein, [(CH 3 ) 3 S] 2 SnCl 6 ·H 2 O is synthesized as a host for dopant ions Bi 3+ and Sb 3+ . The Sb 3+ doped, or Bi 3+ /Sb 3+ co-doped, [(CH 3 ) 3 S] 2 SnCl 6 ·H 2 O has a tunable optical emission spectrum by means of varying dopant ratio and excitation wavelength. As a result, we can achieve single-phase materials suitable for emission ranging from cold white light to warm white light. The intrinsic mechanism is examined in this work, to clarify the dopant effect on the optical properties. The high stability of title crystalline material, against water, oxygen and heat, makes it promising for further application., (© 2024. The Author(s).)

In this study, we identify a novel class of second-order nonlinear optical (NLO) crystals, non-π-conjugated piperazine (H 10 C 4 N 2 , PIP) metal halides, represented by two centimeter-sized, noncentrosymmetric organic-inorganic metal halides (OIMHs), namely H 12 C 4 N 2 CdI 4 ( P 2 1 2 1 2 1 ) and H 11 C 4 N 2 CdI 3 ( Cc ). H 12 C 4 N 2 CdI 4 is the first to be prepared, and its structure contains a CdI 4 tetrahedron, which led to a poor NLO performance, including a weak and non-phase-matchable second harmonic generation (SHG) response of 0.5 × KH 2 PO 4 (KDP), a small birefringence of 0.047 @1064 nm and a narrow bandgap of 3.86 eV. Moreover, H 12 C 4 N 2 CdI 4 is regarded as the model compound, and we further obtain H 11 C 4 N 2 CdI 3 via the replacement of CdI 4 with a highly polarizable CdNI 3 tetrahedron, which results in a sharp enhancement of SHG response and birefringence. H 11 C 4 N 2 CdI 3 exhibits a promising NLO performance including 6 × KDP, 4.10 eV, Δ n = 0.074 @1064 nm and phase matchability, indicating that it is the first OIMH to simultaneously exhibit strong SHG response (>5 × KDP) and a wide bandgap (>4.0 eV). Our work presents a novel direction for designing high-performance NLO crystals based on organic-inorganic halides and provides important insights into the role of the hybridized tetrahedron in enhancing the SHG response and birefringence., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Bismuth-halide-based inorganic-organic hybrid materials (Bi-IOHMs) are desirable in luminescence-related applications due to their advantages such as low toxicity and chemical stability. Herein, two Bi-IOHMs of [Bpy][BiCl 4 (Phen)] ( 1 , Bpy = N -butylpyridinium, Phen = 1,10-phenanthroline) and [PP14][BiCl 4 (Phen)]·0.25H 2 O ( 2 , PP14 = N -butyl- N -methylpiperidinium), containing different ionic liquid cations and same anionic units, have been synthesized and characterized. Single-crystal X-ray diffraction reveals that compounds 1 and 2 crystallize in the monoclinic space group of P 2 1 / c and P 2 1 , respectively. They both possess zero-dimensional ionic structures and exhibit phosphorescence at room temperature upon excitation of UV light (375 nm for 1 , 390 nm for 2 ), with microsecond lifetime (24.13 μs for 1 and 95.37 μs for 2 ). Hirshfeld surface analysis has been utilized to visually exhibit the different packing motifs and intermolecular interactions in 1 and 2 . The variation in ionic liquids makes compound 2 have a more rigid supramolecular structure than 1 , resulting in a significant enhancement in photoluminescence quantum yield (PLQY), that is, 0.68% for 1 and 33.24% for 2 . In addition, the ratio of the emission intensities for compounds 1 and 2 shows a correlation with temperature. This work provides new insight into luminescence enhancement and temperature sensing applications involving Bi-IOHMs.

Recently zero-dimensional (0-D) inorganic-organic metal halides (IOMHs) have become a promising class of optoelectronic materials. Herein, we report a new photoluminescent (PL) 0-D antimony(III)-based IOMH single crystal, namely [H 2 BPZ][SbCl 5 ]·H 2 O (BPZ = benzylpiperazine). Photophysical characterizations indicate that [H 2 BPZ][SbCl 5 ]·H 2 O exhibits singlet/triplet dual-band emission. Density functional theory (DFT) calculations suggest that [H 2 BPZ][SbCl 5 ]·H 2 O has the large energy difference between singlet and triplet states, which might induce the dual emission in this compound. Temperature-dependent PL spectra analyses suggest the soft lattice and strong electron-phonon coupling in this compound. Thermogravimetric analysis shows that the water molecules in the lattice of the title crystal could be removed by thermal treatment, giving rise to a dehydrated phase of [H 2 BPZ][SbCl 5 ]. Interestingly, such structural transformation is accompanied by a reversible PL emission transition between red light (630 nm, dehydrated phase) and yellow light (595 nm, water-containing phase). When being exposed to an environment with 77% relative humidity, the emission color of the dehydrated phase was able to change from red to yellow within 20 s, and the red emission could be restored after reheating. The red to yellow emission switching could be achieved in acetone with water concentration as low as 0.2 vol%. The reversible PL transition phenomenon makes [H 2 BPZ][SbCl 5 ]·H 2 O a potential material for luminescent water-sensing.

An effective ultrasonic-assisted extraction method for the separation of phenolic acids and flavonoids in Cuscuta chinensis Lam. was conducted by combining uniform design (UD) coupled with response surface methodology (RSM) and orthogonal design (OD) experiment. A sensitive and selective high-performance liquid chromatography-electrospray ionization tandem triple quadrupole mass spectrometry (HPLC-ESI-MS/MS) method was applied to quantify the sixteen active ingredients (chlorogenic acid, cryptochlorogenic acid, neochlorogenic acid, isochlorogenic acid A, isochlorogenic acid B, isochlorogenic acid C, caffeic acid, hyperin, isoquercitrin, quercetin, campherol, p -coumaric acid, isorhamnetin, rutin, astragalin, and apigenin). The extraction method was optimized with respect to concentration of extraction solvent, extraction time, and ratio of liquid to solid as a consequence of getting a high sensitive and feasible method for simultaneous determination of contents of multiple components and evaluation of quality control of Cuscuta chinensis Lam. from different origins. It was also considered useful and valuable in the further study for quality control of Cuscuta chinensis Lam.