Low-dimensional organic−inorganic metal halide hybrids (OIMHs) with an ultrabroad-band emission are promising as downconversion phosphors for solid-state lighting. However, toxicity of Pb and low photoluminescence quantum efficiency (PLQE) hamper their application. Herein, two zero-dimensional (0D) lead-free organic antimony (Sb) chloride (Cl) hybrids with dual-band emissions and PLQEs: (TTA) 2 SbCl 5 (TTA = tetraethylammonium) and (TEBA) 2 SbCl 5 (TEBA = benzyltriethylammonium) are reported. Both compounds show a single broad-band orange emission with a near-unity PLQE upon low-energy photons (e.g., 360 nm) excitation. The dual-band emission with an additional blue emission band upon high-energy photons (e.g., 300 nm) excitation enable (TTA) 2 SbCl 5 to be a single-component phosphor for white light emission with a PLQE of 68%, correlated color temperature (CCT) of 2360 K and color rendering index (CRI) of 84. Based on photoluminescence spectra measurements and density functional theory calculations, the dual-band emission is assigned to the radiative recombination from both singlet and triplet self-trapped excitons in inorganic [SbCl 5 ] 2− pyramids. In addition, both luminescent compounds exhibit excellent stability against humidity and thermal attacks. Using (TEBA) 2 SbCl 5 as a yellow downconversion material, highly stable white-light-emitting diodes with a Commission Internationale de l'Eclairage (CIE) of (0.36, 0.33), CCT of 4282 K, and CRI of 82 were demonstrated. These results validate that the title 0D lead-free OIMHs with a dual-band emission and a near-unity PLQE are promising luminescent materials for solid-state lighting.
Much of the genetic predisposition to colorectal cancer (CRC) in humans is unexplained. Studying a Caucasian-dominated population in the United States, we showed that germline allele-specific expression (ASE) of the gene encoding transforming growth factor-β (TGF-β) type I receptor, TGFBR1, is a quantitative trait that occurs in 10 to 20% of CRC patients and 1 to 3% of controls. ASE results in reduced expression of the gene, is dominantly inherited, segregates in families, and occurs in sporadic CRC cases. Although subtle, the reduction in constitutive TGFBR1 expression alters SMAD-mediated TGF-β signaling. Two major TGFBR1 haplotypes are predominant among ASE cases, which suggests ancestral mutations, but causative germline changes have not been identified. Conservative estimates suggest that ASE confers a substantially increased risk of CRC (odds ratio, 8.7; 95% confidence interval, 2.6 to 29.1), but these estimates require confirmation and will probably show ethnic differences.The annual worldwide incidence of colorectal cancer (CRC) exceeds 1 million, being the second to fourth most common cancer in industrialized countries (1). Although diet and lifestyle are thought to have a strong impact on CRC risk, genes have a key role in the predisposition to this cancer. A positive family history of CRC occurs in 20 to 30% of all probands. Highly penetrant autosomal dominant and recessive hereditary forms of CRC account for at most 5% of all CRC cases (2). Although additional high-and low-penetrance alleles have been proposed, much of the remaining predisposition to CRC remains unexplained (3).Aberrations in the transforming growth factor-β (TGF-β) pathway are heavily involved in CRC carcinogenesis (4). Although mutations in the TGF-β type II receptor gene have been explicitly associated with CRC (5), the type I receptor gene (TGFBR1) has received less attention, although there is evidence that a common variant may be associated with cancer risk (6,7). We hypothesized that TGFBR1 is a notable candidate for a gene that, when mutated, causes predisposition to CRC or acts as a modifier of other genes, resulting in a predisposition. Our study was undertaken to test this assumption.
Low-dimensional metal halide hybrids (OIMHs) have recently been explored as single-component white-light emitters for use in solid-state lighting. However, it still remains challenging to realize tunable white-light emission in lead-free zero-dimensional (0D) hybrid system. Here, a combination strategy has been proposed through doping Sb 3+ enabling and balancing multiple emission centers toward the multiband warm white light. We first synthesized a new lead-free 0D (C 8 NH 12 ) 6 InBr 9 •H 2 O single crystal, in which isolated [InBr 6 ] 3− octahedral units are separated by large organic cations [C 8 NH 12 ] + . (C 8 NH 12 ) 6 InBr 9 •H 2 O exhibits dual-band emissions with one intense cyan emission and a weak red emission tail. The low-energy ultrabroadband red emission tail can be greatly enhanced by the Sb 3+ doping. Experimental data and first-principles calculations reveal that the original dominant cyan emission is originated from the organic cations [C 8 NH 12 ] + and that the broadband red emission is ascribed to selftrapped excitons in [In(Sb)Br 6 ] 3− . When the Sb concentration is 0.1%, a single-component warm white-light emission with a photoluminescence quantum efficiency of 23.36%, correlated color temperature of 3347 K, and a color rendering index up to 84 can be achieved. This work represents a significant step toward the realization of single-component white-light emissions in environmental-friendly, high-performance 0D metal halide light-emitting materials.
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