Theoretical Study of the Ternary Compound Monolayer CuP2Se for Photocatalytic Water Splitting with Efficient Optical Absorption.

Utilizing photocatalytic method to produce hydrogen by splitting water is an efficient strategy to solve the hotspot issues of energy crisis and environmental pollution. Herein, we systematically investigate the corresponding properties of the reported Cu-bearing ternary compound monolayer CuP2Se by using the first-principle calculations. The monolayer CuP2Se has quite small cleavage energy of 0.51 J/m2, indicating it can be easily produced by the mechanical exfoliation method experimentally. In addition, it is an indirect bandgap semiconductor material which has a moderate value of 1.91 eV. The conduction band minimum (CBM) and valence band maximum (VBM) can perfectly straddle the redox potentials of water when a biaxial strain of -4% to 4% is applied, unveiling the high photocatalytic thermodynamic stability of monolayer CuP2Se in response to the effect of solvent tension. Remarkably, the monolayer CuP2Se also demonstrates significant sunlight capturing ability in the visible region. The outstanding electronic and optical properties suggest that the monolayer CuP2Se is undoubtedly a viable material for photocatalytic water splitting.

High Curie temperature ferromagnetic monolayer T-CrSH and valley physics of T-CrSH/WS2 heterostructure.

Two-dimensional magnetic materials are attracting widespread attention not only for their excellent applications in spintronic devices but also for their potential to regulate valley splitting, which is crucial for valleytronics. Herein, we design a monolayer Janus ferromagnetic semiconductor T-CrSH by using first-principles calculations. We reveal that monolayer T-CrSH has a magnetic moment of 3µB per unit cell, which is primarily contributed by the 3d orbitals of the Cr atom. Monte Carlo simulations suggest that the Curie temperature of T-CrSH is 193 K, and it can rise to 402 K when a 5% tensile strain is applied. Furthermore, the valley degeneracy of WS2 can be lifted when monolayer T-CrSH is used as a substrate. The obtained valley splitting in the conduction band is 13.7 meV and that in the valence band is 157.5 meV. In addition, the large valley polarization of 12.8 meV in the conduction band makes it easy to achieve an electron-doped valley Hall current and spin Hall current when performing in an in-plane electric field.

Photocatalytic water splitting for hydrogen production with high efficiency monolayer In2Te5: a theoretical study.

Employing density functional theory (DFT) calculations, we explore the excellent performance of two-dimensional (2D) semiconductor In2Te5 in photocatalytic water splitting at the theoretical level. The calculated results illustrate that 2D In2Te5 is a direct band gap semiconductor with a moderate band gap value and an ultrahigh optical absorption coefficient in the visible light region. It was found that its conduction band edge is higher than the reduction potential of water (-4.44 eV), which proves that it can split water to produce hydrogen. Furthermore, its excellent hydrogen evolution activity can be tuned under an appropriate biaxial strain. In addition, 2D In2Te5 shows a remarkable photo-generated current, suggesting that electrons and holes can be separated efficiently. Our results offer a superior candidate material for realizing photocatalytic water splitting for hydrogen evolution.

Quasi-One-Dimensional Structure and Possible Helical Antiferromagnetism of RbMn6Bi5.

Quasi-one-dimensional materials exhibit not only unique crystal structure but also abundant physical properties such as charge density wave, Luttinger liquid, and superconductivity. Here we report the discovery, structure, and physical properties of a new manganese-based quasi-one-dimensional material RbMn6Bi5, which crystallizes in a monoclinic space group C2/m (No. 12) with lattice parameters a = 23.286(5) Å, b = 4.6215(9) Å, c = 13.631(3) Å, and ß = 125.00(3)°. The structure features [Mn6Bi5]-1 double-walled column extending along the [010] direction, together with Bi-Bi homoatomic bonds linking the columns and the countercation Rb+. The temperature-dependent resistivity clearly indicates a significant resistivity anisotropy for RbMn6Bi5, whereas the magnetic susceptibility and specific heat measurements show that RbMn6Bi5 is antiferromagnetic below 82 K. The density functional theory calculations indicate that RbMn6Bi5 is a quasi-one-dimensional metal with possible helical antiferromagnetic configuration. The discovery of RbMn6Bi5 confirms the viability of discovering new quasi-one-dimensional materials in manganese-based compounds.

Sequence analysis of α-(1, 2)-fucosyltransferase gene in nine Chinese individuals with Para-Bombay phenotype.

BACKGROUND: To analyze the sequence of α-(1, 2)-fucosyltransferase gene (FUT1) in nine individuals with Para-Bombay phenotype. METHODS: Para-Bombay phenotype was defined according to the serologic characteristics and ABO genotypes. The full coding region of FUT1 was amplified, genotype and haplotype were analyzed by direct and TOPO cloning sequencing which was used to discriminate heterozygous mutations of FUT1. RESULTS: These nine individuals were identified as three Para-Bombay A (Ah), six Para-Bombay B (Bh) according to serologic characteristics and ABO genotypes. According to the direct and cloning sequencing results of the full coding region of FUT1, five genotypes and five haplotypes were found in these nine individuals. CONCLUSION: Two complex mutations of FUT1 were discovered, which were h1h547 - 552delAG + 814A > G (c.547 - 552delAG, p.Arg183Argfs ∗ 86; c.547 - 552delAG, p.Arg183Argfs ∗ 86 + c.814A > G, p.lle272Val) and h755G > Ch547 - 552delAG + 755G > C (c.755G > C, p.Arg183Argfs ∗ 86; c.547 - 548delAG, p.Arg183Argfs ∗ 86 + c.755G > C, p.Arg253Pro), the genotype of h755G > Ch547 - 552delAG + 755G > C was reported for the first time, and three kinds of known genotype (h1h1, h3h3, h1h3) were found also in these nine Chinese individuals with Para-Bombay phenotype in the present study. In this way, the FUT1 mutation showed a distinct geographic and ethnic range.