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Lithium sulfide (Li2S) plays an important role in fields such as energy, environment and semiconductors. Exploration of the microstructure of Li2S has significant implications for developing new materials and optimizing related material properties. In this work, the inverse design of materials by the multi-objective differential evolution (IM2ODE) method combined with density functional theory (DFT) calculations was used to predict the two-dimensional (2D), three-dimensional (3D), and cluster structures of Li2S. Their structural stabilities and electronic properties were further investigated. Novel monolayer and double-layer hexagonal structures of 2D Li2S are predicted. The double-layer structure has better thermal stability and a wider band gap of 3.5 eV than the single-layer structure. Various novel structures of 3D Li2S are predicted. Some structures are similar to 1T-MoS2 and the double-layer hexagonal structure of 2D Li2S. With increasing number of atoms, the (Li2S)n clusters converge into a cage-like structure and their average binding energies decrease. The second-order energy differences of (Li2S)n clusters show an odd–even oscillation rule. The ionization potentials, electron affinities, electronegativities, and chemical hardnesses also decrease. These findings should improve theoretical understanding of the properties and behavior of new 2D, 3D, and cluster functional materials. [ABSTRACT FROM AUTHOR]

Herein, we investigated in detail the effect of metal valences in different cobalt‐based organic framework compounds on the kinetics of sulfur reaction in lithium‐sulfur batteries (LSBs). On this basis, two organic framework compounds of zeolite‐imidazole‐based cobalt organic framework compound (Co‐ZIF) and tetrakis(4‐benzoic acid) porphyrinato‐CoIII chloride [Co‐TBP(III)] with different valences were constructed as the functional intercalation separators of LSBs, and explored the effects of different valences on improving the reaction kinetics of polysulfides and inhibiting the shuttle effect. Experiments and theoretical calculations prove that CoII exhibits the best catalytic activity. This is mainly due to the fact that +2 valence shows a strong adsorption energy for polysulfides and a higher Fermi level compared with +3 valence, thus improving the efficiency of the rapid catalytic conversion of sulfur species. As expected, the discharge specific capacity of Co‐ZIF as the catalytic layer of the LSBs reached 772.7 mAh g−1 at a high current density of 5 C. More importantly, the initial specific capacity is 839.6 mAh g−1 at high current 3 C, and after 720 cycles, the attenuation rate of per cycle is only 0.092 %, and the coulombic efficiency remains above 92 %. [ABSTRACT FROM AUTHOR]

The sluggish kinetics in multistep sulfur redox reaction with different energy requirements for each step, is considered as the crucial handicap of lithium–sulfur (Li–S) batteries. Designing an electron reservoir, which can dynamically release electron to/accept electron from sulfur species during discharge/charge, is the ideal strategy for realizing stepwise and dual‐directional polysulfide electrocatalysis. Herein, a single Tb3+/4+ oxide with moderate unfilled f orbital is synthetized as an electron reservoir to optimize polysulfide adsorption via Tb–S and N···Li bonds, reduce activation energy barrier, expedite electron/Li+ transport, and selectively catalyze both long‐chain and short‐chain polysulfide conversions during charge and discharge. As a result, Tb electron reservoir enables stable operation of low‐capacity decay (0.087% over 500 cycles at 1 C), high sulfur loading (5.2 mg cm−2) and electrolyte‐starved (7.5 μL mg−1) Li–S batteries. This work could unlock the potential of f orbital engineering for high‐energy battery systems. [ABSTRACT FROM AUTHOR]

As an important inorganic material, zirconium dioxide (ZrO2) has a wide range of applications in the fields of microelectronics, coating, catalysis and energy. Due to its high dielectric constant and thermodynamic stability, ZrO2 can be used as dielectric material to replace traditional silicon dioxide. Currently, ZrO2 dielectric films can be prepared by atomic layer deposition (ALD) using water and zirconium precursors, namely H2O-based ALD. Through density functional theory (DFT) calculations and first-principles molecular dynamics (FPMD) simulations, the adsorption and dissociation of water molecule on the ZrO2 surface and the water–solid interface reaction were investigated. The results showed that the ZrO2 (111) surface has four Lewis acid active sites with different coordination environments for the adsorption and dissociation of water. The Zr atom on the surface can interacted with the O atom of the water molecule via the p orbital of the O atom and the d orbital of the Zr atom. The water molecules could be dissociated via the water–solid interface reaction of the first or second layer of water molecules with the ZrO2 (111) surface. These insights into the adsorption and dissociation of water and the water–solid interface reaction on the ZrO2 surface could also provide a reference for the water–solid interface behavior of metal oxides, such as H2O-based ALD. [ABSTRACT FROM AUTHOR]

Lead-free zero-dimensional (0D) perovskite nanocrystals (NCs) with isolated octahedral structures have attracted considerable attention due to their unique photoelectric properties, such as highly efficient emissions with broadband features. A series of phosphors composed of Sb3+-doped 0D perovskite crystals Cs3ZnCl5 with wavelength-tunable emission spectra have been obtained using a facile recrystallization method at room temperature in air. By controlling the doping concentration of Sb3+ in Cs3ZnCl5 lattice, bright emissions from red to orange have been achieved under excitation at 320 nm due to the expansion of the crystal lattice, and the emission excited at 275 nm is bluish-white, spanning the full visible region. Inductively coupled plasma emission spectrometry (ICP) demonstrates the Sb3+ substitutes for Zn2+ rather than Cs+ due to the similar charges and ionic radii. The luminescence performance of phosphor Cs3ZnCl5:Sb3+ can be improved obviously by replacing 3 mol% of Cs+ with Rb+ or K+ due to the further distortion of the crystal lattice. The present approach allows the synthesis of large-scale emissive lead-free 0D perovskites activated by Sb3+ with tunable luminescence color. [ABSTRACT FROM AUTHOR]