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Zn–Al layered double hydroxides (Zn–Al LDHs) with various reaction times were synthesized by a hydrothermal method at constant pH, and they were tested for the removal of RhB with or without post-calcination treatment.

A novel 2D porous NiCoSe nanosheet arrays were grown on Ni foam using ZIF-67 as precursors, which exhibited outstanding bifunctional electrocatalytic activity and superior durability for overall water splitting.

The structural stability, magnetic properties and electronic structure of tetragonal BiCoO(3) under pressure have been studied by first-principles density functional calculations. The calculated results reveal that no tetragonal-to-cubic and ferroelectric-to-paraelectric phase transitions occur up to 30 GPa with a volume compression of about 25%. An electronic spin crossover transition of the Co(3+) ion from the high-spin to nonmagnetic low-spin configuration (magnetic moment collapse) occurs at 4 GPa by about 4.87% volume compression, which is concomitant with a first-order isosymmetric transition and an insulator-to-semimetal transition. The metallization in BiCoO(3) is driven by the spin-state transition at high pressure. Coexistence of the structural, spin-state and insulator-to-semimetal transitions implies that there is a strong coupling among the lattice, spin and charge degrees of freedom in BiCoO(3).

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The electronic structure of room-temperature (RT) phase α -NaV 2 O 5 has been investigated by fully self-consistent first-principles calculations based on density functional theory (DFT). For the crystallographic unit cell, a nonmagnetic (NM) metallic solution is obtained by spin-restricted generalized gradient approximation (GGA) calculations, whereas a ferromagnetic (FM) insulating solution is successfully simulated within the spin-polarized GGA. An insulating antiferromagnetic (AFM) state with lower energy is obtained for the 1 × 2 × 1 crystallographic supercell. The magnetic S = 1/2 electrons are fully spin-polarized and delocalized on the V-O-V molecular orbitals (along the rung), where the net spin magnetic moments amount to 0.96 μ B on the V-O-V rungs of the ladder derived from Mulliken population analysis. The intra-rung vanadium d xy orbitals form the bonding-antibonding orbitals split by inter-orbital interactions. It is not the on-site Coulomb interaction, but the AFM spin exchange couplings that lead to the half-filled bonding orbitals splitting and forming a magnetic insulating gap. The present spin-polarized DFT calculations reveal that α -NaV 2 O 5 (RT) is a Slater insulator. The calculated electronic structure explains the controversial topics of the absorption peak in the optical spectra and the energy loss peak in the resonant inelastic x-ray scattering (RIXS).

Hexagonal Ag nanoparticle arrays are exclusively grown on top of the interstices of Au nanobowl arrays.