Circularly Polarized Light-Dependent Pyro-Phototronic Effect from 2D Chiral-Polar Double Perovskites.

Chiral hybrid perovskites combine the advantages of chiral materials and halide perovskites, offering an ideal platform for the design of circularly polarized light (CPL) detectors. The pyro-phototronic effect, as a special mechanism of the photoexcited pyroelectric signal, can significantly improve the performance of photodetectors, whereas it remains a great challenge to achieve pyroelectricity-based CPL detection. In this work, the chiroptical phenomena and the pyro-phototronic effect are combined in chiral-polar perovskites to achieve unprecedented pyroelectric-based CPL detection. Two novel two-dimensional (2D) lead-free chiral-polar double perovskites, S/R-[(4-aminophenyl)ethylamine]2AgBiI8·0.5H2O, are successfully designed and synthesized by introducing chiral organic ligands into metal halide frameworks. Strikingly, the photoresponse is substantially boosted with the support of the pyro-phototronic effect, showing an increased pyro-phototronic current that is 40 times greater than the photovoltaic current. Furthermore, the pyroelectric-based detector possesses excellent CPL detection capacity to distinguish different polarization states of CPL photons, which achieve an impressive glph of up to 0.27 at zero bias. This study provides a brand new process for CPL detection by utilizing the pyro-phototronic effect in chiral-polar perovskites, which opens a new avenue for chiral materials in optoelectronic applications.

Realization of Passive X-Ray Detection with a Low Detection Limit in Dion-Jacobson Halide Hybrid Perovskite.

Halide hybrid perovskites are a kind of intriguing contenders for X-ray detection, and their low detection limits (LoDs) have played a crucial part in X-ray safety inspection and medical examination. However, there is still a significant challenge in manufacturing perovskite X-ray detectors with low LoDs. Herein, attributed to the bulk photovoltaic effect (BPVE) of a Dion-Jacobson (DJ) type 2D halide hybrid perovskite polar structure (3-methylaminopropylamine)PbBr4 (1), self-powered X-ray detection with low detection limit is successfully realized. Specifically, the crystal-based detector of 1 exhibits a low dark current at zero bias, which reduces the noise current (0.34 pA), leading to a low detection limit (58.3 nGyair s-1 ) which is two orders of magnitude lower than that of under external voltage bias. The combination of BPVE and LoDs of halide hybrid perovskite provides an efficient strategy to achieve passive X-ray detection with low doses.

Localized Lattice Expansion of FAPbBr3 to Design a 3D Hybrid Perovskite for Sensitive Near-Infrared Photodetection.

A mixed-cation 3D lead bromide hybrid perovskite (NMDAP)2 FAPb4 Br13 (1, NMDAP2+ = N-methyl-1,3-diaminopropanium, FA+ = formamidinium) is tailored by incorporating the large NMDAP2+ cation with the small FA+ ion into 3D FAPbBr3 . Structurally, the small FA+ ions occupy the prototypical cavities formed by distorted corner-sharing PbBr6 octahedra as in FAPbBr3 , while the bulky NMDAP2+ ions are confined to the expanded lattice which is defined by a new structural motif composed of eight corner-sharing PbBr6 octahedra and four edge-sharing octahedra. This localized lattice expansion from FAPbBr3 creates a new branch of the intriguing 3D hybrid perovskite family, breaking the limits of the conventional Goldschmidt tolerance factor rule. Moreover, a high two-photon absorption (2AP) coefficient of 60.8 cm MW-1 was demonstrated to near-infrared (NIR) 800 nm illumination, enabling sensitive NIR photoresponses with large on/off ratio (≈104 ) as well as favorable stability.

Highly efficient electrochemiluminescence based on 4-amino-1,2,4-triazole Schiff base two-dimensional Zn/Cd coordination polymers.

Four coordination polymers, formulated as [Zn(L1)2]n (1), [Cd(L1)2]n (2), [Zn(L2)2]n (3) and [Cd(L2)2]n (4) (HL1 is (E)-2-(((4H-1,2,4-triazol-4-yl)imino)methyl)-4,6-dibromophenol; HL2 is (E)-2-(((4H-1,2,4-triazol-4-yl)imino)methyl)-4,6-dichlorophenol) have been synthesized through vial reactions. The four compounds were structurally characterized by single crystal X-ray diffraction, elemental analysis, PXRD, and fluorescence spectroscopy. For 1-4, a detailed analysis of Hirshfeld surfaces and fingerprint plots facilitates a comparison of intermolecular interactions, which are crucial in building different supramolecular architectures. C-HX (X = Br, Cl) interactions play a crucial role in stabilizing the self-assembly process among adjacent 2-D networks for both complexes. Above all, complexes 1-4 showed highly intense electrochemical luminescence (ECL) in DMF solution and high thermal stability.

Genome-wide association study for pigmentation traits in Chinese Holstein population.

With the Illumina BovineSNP50K BeadChip, we performed a genome-wide association study (GWAS) for two pigmentation traits in a Chinese Holstein population: proportion of black (PB) and teat colour (TC). A case-control design was used. Cases were the cows with PB <0.30 (n = 129) and TC <2 points (n = 140); controls were those with PB >0.90 (n = 58) and TC >4 points (n = 281). The RM test of roadtrips (version 1.2) was applied to detect SNPs for the two traits with 42 883 and 42 741 SNPs respectively. A total of nine and 12 genome-wide significant (P < 0.05) SNPs associated with PB and TC respectively were identified. Of these, two SNPs for PB were located within the KIT and IGFBP7 genes, and the other four SNPs were 23~212 kb away from the PDGFRA gene on BTA6; nine SNPs associated with TC were located within or 21~78.8 kb away from known genes on chromosomes 4, 11, 22, 23 and 24. By combing through our GWAS results and the biological functions of the genes, we suggest that the KIT, IGFBP7, PDGFRA, MITF, ING3 and WNT16 genes are promising candidates for PB and TC in Holstein cattle, providing a basis for further investigation on the genetic mechanism of pigmentation formation.