Improving the sulfur loading in cathodes is a significant challenge for practical lithium−sulfur batteries. Although carbonaceous sulfur hosts can achieve higher sulfur content and loading, the low tap densities of carbonaceous materials lead to low volumetric energy densities, restricting practical application. Here, conductive porous laminated vanadium nitride (VN) as a carbon-free sulfur host has been successfully developed to construct high tap density, high sulfur loading, and high energy density sulfur electrodes. The laminated stacking multiscale VN featuring interconnected holes possesses high storage space for sulfur loading, achieving high sulfur loading and utilization. VN@S materials' sulfur content and tap density can achieve 80 wt % and 1.17 g cm −3 , respectively. At the sulfur loading of 1.0 mg cm −2 , the VN@S cathode reaches the reversible capacity of 790 mAh g −1 at 1 C after 200 cycles and 145.2 mAh g −1 at 15 C after 500 cycles. Precisely, at a high sulfur loading of 12.6 mg cm −2 , the VN@S cathode delivers a reversible capacity of 518.8 mAh g −1 (485.6 mAh cm −3 ) at 0.1 C after 100 cycles.

Herein, two-dimensional materials for photocatalytic water splitting are drawing more attention due to the larger surface areas for photocatalytic reactions and shorter migration distances for photogenerated carriers. In this present study, we systematically investigated the fundamental electronic properties of GaSTe monolayers (x = 0, 0.125, 0.25, 0.5, 0.75, 0.875, and 1) for water splitting based on density functional theory (DFT) using the HSE06 functional. The simulation of the defect formation energy under each experimental synthetic condition shows that the Te substitutional impurity in GaS can be relatively easily realized under Ga-rich conditions. Our results show that the GaSTe monolayer is a direct band gap (2.09 eV) semiconductor, which is attributed to the elevation of Te p/p states at the Γ point by the strain effect. Moreover, the GaSTe monolayer has appropriate band edge alignment with respect to the water redox potentials in both acidic and neutral environments. Additionally, the carrier effective mass of the GaSTe monolayer along the direction of Γ → K is smaller than those of pristine GaS and GaTe monolayers, which can cause the carriers to quickly transfer from the photogenerated center to the surface of the photocatalyst. These results imply that the GaSTe monolayer is a promising candidate as a visible-light water splitting photocatalyst, which should be properly synthesized and tested in further experimental investigations.

A series of high-pressure measurements including resistivity, ac/dc magnetic susceptibility, neutron powder diffraction and synchrotron x-ray diffraction were performed to investigate the crystal structure and electronic states of the itinerant ferromagnet SrCoO 3 . Two pressure-induced phase transitions were observed at about 1.1 GPa and 45 GPa, corresponding to a spin reorientation and a spin state transition, respectively, while the cubic crystal structure was stable with pressure up to 60.0 GPa.The origins of these electronic state changes are discussed and rationalized in the light of first-principles calculations.

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