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C38H34Ni2Cl2N4O12, monoclinic, C2/c (no. 15), a = 17.867(3) Å, b = 9.170(6) Å, c = 24.651(5) Å, β = 110.837(2)°, Z = 4, V = 3775(3) Å3, Rgt(F) = 0.0323, wRref(F2) = 0.1078, T = 293(2) K. [ABSTRACT FROM AUTHOR]

In the current research, the moisture-resistant of Mg-MOF-74 was successfully improved by coating with two-dimensional (2-D) hexagonal boron nitride (h -BN) during the facile hydrothermal synthesis process. Both TEM and SEM results revealed that 2-D h -BN is coated on Mg-MOF-74's surface. The crystal structure, morphology, surface area, thermal stability and CH 4 uptake capacity of Mg-MOF-74 were not drastically influenced by coating with h -BN as examined by XRD, FTIR, SEM, and TEM. Further, the coated Mg-MOF-74 demonstrated better stability than uncoated Mg-MOF-74, when being exposed to high humidity, in terms of surface area and CH 4 uptake capacity. It was observed that the coated Mg-MOF-74 with 1 ​wt % h -BN has reached to 1959 ​m2 ​g−1 surface area and CH 4 uptake capacity of 43 ​cm3 ​g−1 after exposure to high humidity for a duration of 1 month. Thus, this research work has opened a new window towards the improvement of the water stability of Mg-MOF-74. [Display omitted] • The water resistance capacity of Mg-MOF-74 could be improved by coating with two dimensional materials h -BN. • Application of h -BN as coating material of Mg-MOF-74. • h -BN coated Mg-MOF-74 provide high surface area and enhanced CH 4 uptake capacity. • The sample Mg-MOF-74@1 wt.% h -BN exhibited the highest water stability. [ABSTRACT FROM AUTHOR]

Here, crystal structure, electronic structure, chemical substitution, pressure-dependent superconductivity, and thickness-dependent properties in FeSe-based superconductors are systemically reviewed. First, the superconductivity versus chemical substitution is reviewed, where the doping at Fe or Se sites induces different effects on the superconducting critical temperature (Tc). Meanwhile, the application of high pressure is extremely effective in enhancing Tc and simultaneously induces magnetism. Second, the intercalated-FeSe superconductors exhibit higher Tc from 30 to 46 K. Such an enhancement is mainly caused by the charge transfer from the intercalated organic and inorganic layer. Finally, the highest Tc emerging in single-unit-cell FeSe on the SrTiO3 substrate is discussed, where electron-phonon coupling between FeSe and the substrate could enhance Tc to as high as 65 K or 100 K. The step-wise increment of Tc indicates that the synergic effect of carrier doping and electron-phonon coupling plays a critical role in tuning the electronic structure and superconductivity in FeSe-based superconductors. [ABSTRACT FROM AUTHOR]

Three layered compounds CsLiCoS 2 , CsAgCoS 2 and CsLiFeS 2 have been synthesized by conventional solid-state reaction method. All of three compounds exhibit semiconducting behavior in electrical transport with small thermal activation energy gap. The crystal structure of CsLiCoS 2 is isostructural to ThCr 2 Si 2 -type CsCo 2 S 2 with random mixture of Li+ and Co2+. The latter two compounds exhibit √2 ​× ​√2 ​× ​1 superstructure of ThCr 2 Si 2 -type because the monovalent Ag+/Li+ and divalent Co2+/Fe2+ independently occupy inequivalent sites in [AMS 2 ]- layer. Through comprehensive investigation of the crystallographic lattice in CsAMS 2 , a phase boundary between disorder and ordered phases may be identified, which highlights the importance of the atomic size and lattice mismatch in determining the crystal structure. Image 1 • Three layered sulfides CsAMS 2 (A ​= ​Li, Ag; M ​= ​Co, Fe) are synthesized by solid state reaction method. • Introducing monovalent Li+/Ag+ could significantly change the structure and property of Co-based sulfides. • A phase boundary between random and ordered occupation in the [AMS 2 ]- layers is determined by the atomic size difference. [ABSTRACT FROM AUTHOR]