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One of the great advantages of organic–inorganic metal halides is that their structures and properties are highly tuneable and this is important when optimizing materials for photovoltaics or other optoelectronic devices. One of the most common and effective ways of tuning the electronic structure is through anion substitution. Here, we report the inclusion of bromine into the layered perovskite [H3N(CH2)6NH3]PbBr4to form [H3N(CH2)6NH3]PbBr4·Br2, which contains molecular bromine (Br2) intercalated between the layers of corner-sharing PbBr6octahedra. Bromine intercalation in [H3N(CH2)6NH3]PbBr4·Br2results in a decrease in the band gap of 0.85 eV and induces a structural transition from a Ruddlesden–Popper-like to Dion–Jacobson-like phase, while also changing the conformation of the amine. Electronic structure calculations show that Br2intercalation is accompanied by the formation of a new band in the electronic structure and a significant decrease in the effective masses of around two orders of magnitude. This is backed up by our resistivity measurements that show that [H3N(CH2)6NH3]PbBr4·Br2has a resistivity value of one order of magnitude lower than [H3N(CH2)6NH3]PbBr4, suggesting that bromine inclusion significantly increases the mobility and/or carrier concentration in the material. This work highlights the possibility of using molecular inclusion as an alternative tool to tune the electronic properties of layered organic–inorganic perovskites, while also being the first example of molecular bromine inclusion in a layered lead halide perovskite. By using a combination of crystallography and computation, we show that the key to this manipulation of the electronic structure is the formation of halogen bonds between the Br2and Br in the [PbBr4]∞layers, which is likely to have important effects in a range of organic–inorganic metal halides.

ABSTRACTThe clinicopathological value of microRNA-141-3p (miR-141-3p) and its prospective target genes in endometrial carcinoma (EC) remains unclear. The present study determined the expression level of miR-141-3p in EC via quantitative real-time PCR (RT-qPCR). RT-qPCR showed a markedly higher expression level of miR-141-3p in EC tissues than in non-EC endometrium tissues (P< 0.0001). The microarray and miRNA-seq data revealed upregulation of miR-141-3p. Integrated analysis based on 675 cases of EC and 63 controls gave a standardized mean difference of 1.737, confirmed the upregulation of miR-141-3p. The Kaplan-Meier survival curve showed that a higher expression of miR-141-3p positively corelated with a poorer prognosis. Combining the predicted targets and downregulated genes in EC, we obtained 271 target genes for miR-141-3p in EC. Two potential targets, PPP1R12A and PPP1R12B, were downregulated at both the mRNA and protein levels. This study indicates that the overexpression of miR-141-3p may play an important part in the carcinogenesis of EC. The overexpression of miR-141-3p may be a risk factor for the prognosis of patients with EC.

We present three new hybrid layered lead(II) bromide perovskites of generic composition A2PbBr4or AA′PbBr4that exhibit three distinct structure types. [TzH]2PbBr4([TzH+] = 1,2,4-triazolium) adopts a (001)-oriented layer structure and [AaH]2PbBr4, ([AaH+] = acetamidinium) adopts a (110)-oriented type, whereas [ImH][TzH]PbBr4, ([ImH+] = imidazolium) adopts a rare (110)-oriented structure with enhanced corrugation (i.e., 3 × 3 type). The crystal structures of each are discussed in terms of the differing nature of the templating molecular species. Photoluminescent spectra for each are reported and the behaviors discussed in relation to the different structure of each composition.