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Organic‐inorganic hybrid multifunctional materials have shown significant application in lighting and sensor fields, owing to their prominent performance and diversity structures. Herein, we synthesized two multifunctional compounds: (propyl‐quinuclidone)2CdBr4 (1) and (F‐butyl‐quinuclidone)2CdBr4 (2). By introducing light‐emitting organic cation with flexible long chain, 1 and 2 exhibit excellent transition properties and bright blue‐white fluorescence. Then, combine fluorescence lifetime and first‐principal calculation, providing evidence for the electron transfer emission. Subsequently, investigated the impact of substituent carbon chain length (methyl to butyl), structural rigidity (C−C to C−F) and halide framework (Cl to I) on the fluorescence properties. Results indicate that Cd⋅⋅⋅Cd distance and structural rigidity play an important role in fluorescence. Overall, our research provides valuable insight and example for chemical modifications enhance compound performance. [ABSTRACT FROM AUTHOR]

Hybrid organic‐inorganic perovskites (HOIP) due to their excellent optoelectronic properties and flexible structure have attracted enthusiastic interest. In particular, introducing chirality is a method to enhance compound performance. Herein, we report a multifunctional compound: (3APr)PbBr4 (1) (3APr=3‐Pyrrolidinamine) and corresponding enantiomer R and S‐(3APr)PbBr4 (R/S‐2). Compound 1 show reversible solid‐state phase transition, step‐like dielectric anomaly and broadband yellow emission under uv light excitation. Accompany with phase transition, structure dimension transition from 2D to 1D without space group change. Through introduce chirality, the R/S‐2 display mirror image 1D structural relationship, increased quantum yield from 3.43 % (1) to 13.65 % (R/S‐2) and exhibits corresponding CD signals. Then combine to first‐principles analysis, it was found that fluorescence is attributed to the formation of instantaneous defects during excitation, leading to the formation of self‐trapped excitons (STEs). This finding will further promote the development of multifunctional compound and the study of chiral substitution enhance compound properties. [ABSTRACT FROM AUTHOR]

Hybrid organic‐inorganic perovskites (HOIP) due to their excellent optoelectronic properties and flexible structure have attracted enthusiastic interest. In particular, introducing chirality is a method to enhance compound performance. Herein, we report a multifunctional compound: (3APr)PbBr4 (1) (3APr=3‐Pyrrolidinamine) and corresponding enantiomer R and S‐(3APr)PbBr4 (R/S‐2). Compound 1 show reversible solid‐state phase transition, step‐like dielectric anomaly and broadband yellow emission under uv light excitation. Accompany with phase transition, structure dimension transition from 2D to 1D without space group change. Through introduce chirality, the R/S‐2 display mirror image 1D structural relationship, increased quantum yield from 3.43 % (1) to 13.65 % (R/S‐2) and exhibits corresponding CD signals. Then combine to first‐principles analysis, it was found that fluorescence is attributed to the formation of instantaneous defects during excitation, leading to the formation of self‐trapped excitons (STEs). This finding will further promote the development of multifunctional compound and the study of chiral substitution enhance compound properties. [ABSTRACT FROM AUTHOR]

Bromine exists mainly as ions in bromide brine and halide sulfate brine in the hydrosphere of the crust. Powder carrier pellet method is commonly used in analyzing bromine in brine by Wavelength Dispersive X-ray Fluorescence Spectrometry (WDXRF). However, this sample preparation method has the disadvantages of large work load, sample inhomogeneity and outer contamination, which affects the analytical accuracy. Samples were pretreated by film adsorption, and film material and sample weight were optimized and are reported in this paper. Firstly, 50 μL of brine is dropped to the center of a chromatography filter paper (Ф=40 mm), air dried, and then flattened by high pressure to prepare the film sample for WDXRF test. A standard curve of Br was calibrated by self-prepared standard solution. Experimental results show that the impact of coexisting ions such as K+, Na+, Ca2+, Mg2+, Cl- and SO42- on the detection of Br is negligible. The detection limit of this method is 0.95 mg/L, the precision is less than 0.8% (n=11), and the recoveries are 99.4%-101.2%. The new sample preparation method is very economical and easy to operate, avoiding the use of chemical reagent.

Organic–inorganic hybrid metal halides for high-temperature phase transition have become increasingly popular owing to their wide operating temperature range in practical applications, e.g., energy storage, permittivity switches and opto-electronic devices. This paper describes the subtle assembly of two new hybrid perovskite crystals, [Cl-C6H4-(CH2)2NH3]2CdX4 (X = Br 1; Cl 2), undergoing high-T reversible phase transformations around 335 K/356 K. Differential scanning calorimetry (DSC), differential thermal analysis (DTA) and VT PXRD tests uncover their reversible first-order phase transition behaviors. Furthermore, the compounds exhibit switchable dielectricity near T, making them potential dielectric switching materials. Hirshfeld surface analysis well discloses a distinct difference in hydrogen-bonding interaction between 1 and 2. UV spectra and computational analysis demonstrate that the compounds are a type of direct-band-gap semiconductor. This research will contribute an effective approach to the structure and development of multifunctional molecular hybrid crystals. [ABSTRACT FROM AUTHOR]

Organic‐inorganic hybrid multifunctional materials have received significant attention due to their potential applications in smart devices such as phase‐change memory (PCM), resistive random‐access memory (ReRAM). Yet, devices application requires achieving a balance between fast switching speeds, long‐term stability, and high cycling endurance in materials still facing difficulties. Herein, we report two hybrid phase transition compounds: (CMQ)BiCl5(CMQ=Chloromethyl Quinuclidin‐3‐one) (1) and (FMQ)2SbBr5(FMQ=Fluoromethyl Quinuclidin‐3‐one) (2), both two compounds exhibit high phase transition temperature, dual‐stable behavior in dielectric during reversible phase transition process. Notably, 1 exhibit small dielectric change after multiple dielectric state switching. Furthermore, investigate the influence of halogen substitution (F to Cl) for compound properties, which show an Increasing transition temperature (9 K) and raising structural dimension (0D to 1D). Additionally, using first principles, analyze the electronic structure of 1 and find that it has a 3.4 eV wide bandgap, closing to GaN semiconductor (3.4 eV). This work provides a new insight into developing the next‐generation phase transition compounds and chemical modification enhances material performance. [ABSTRACT FROM AUTHOR]