Search

Sulfide solid electrolytes (SSEs) have become an ideal candidate material for all‐solid‐state Li metal batteries (ASSLMBs) because of their high ionic conductivity. However, the vile Li incompatibility and poor air stability of SSEs barriers their commercial application. Herein, novel Li6+2xP1−xInxS5−1.5xO1.5xCl (0 ≤ x ≤ 0.1) SSEs are synthesized via In and O co‐doped Li6PS5Cl. By regulating the substitution concentration, the prepared Li6.12P0.92In0.08S4.88O0.12Cl exhibits considerable ionic conductivity (2.67 × 10−3 S cm−1) and enhanced air stability. Based on the first‐principles density functional theory (DFT) calculation, it is predicted that In3+ replaces P5+ to form InS45− tetrahedron and O2− replaces S2− to form PS3O4− group. The mechanism of enhancing air stability by In, O co‐substituting Li6PS5Cl is clarified. More remarkably, the formation of Li‐In alloys induced by Li6.16P0.92In0.08S4.88O0.12Cl electrolyte at the anode interface is beneficial to reducing the migration barrier of Li‐ions, promoting their remote migration, and enhancing the stability of the Li/SSEs interface. The optimized electrolyte shows superior critical current density (1.4 mA cm−2) and satisfactory Li dendrite inhibition (stable cycle at 0.1 mA cm−2 over 3000 h). The ASSLMBs with Li6.16P0.92In0.08S4.88O0.12Cl electrolyte reveal considerable cycle stability. This work emphasizes In, O co‐doping to address redox issues of sulfide electrolytes. [ABSTRACT FROM AUTHOR]

The photogalvanic effect (PGE) generated under linearly polarized light irradiation has remarkable applications in 2D nanodevices. The PGE of 2D WS2/Mo2CF2 van der Waals (vdW) heterostructure can generate photocurrent and high sensitivity to polarized light. However, the PGE has less photogenerated current. On this basis, the photocurrent transport mechanism of PGE under low bias voltage is investigated. The results show that the photocurrent of the photon energy has cos2θ, sin2θ and sin2θ dependence on the polarization angle θ under the considered external bias voltage. Under a bias voltage of 1.0 V, the maximum photocurrent of 3.7 eV photon energy in the zigzag direction can reach 4.61. Under a bias voltage of 1 V, the maximum photocurrent of 1.8 eV photon energy in the armchair direction can reach 6.71. The maximum photocurrents are in the order of 10−1 for both zigzag and armchair directions with 0 V bias. Furthermore, 2D WS2/Mo2CF2 vdW heterostructure has a stable and high extinction ratio. These results show that 2D WS2/Mo2CF2 vdW heterostructure is a potential candidate material for future optoelectronics in the visible light region. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) van der Waals (vdW) heterostructures have attracted much attention due to their unique properties in photocatalysis, electronics, and energy storage. This work comprehensively analyzed the electronic properties and photocatalytic efficiency properties of 2D vdW MoS2/Hf2CO2 heterostructure by first-principles calculations and molecular dynamics simulation. An ideal band gap of 1.44 eV was found for visible light absorption. Meanwhile, a high solar-to-hydrogen efficiency of 17.14% is obtained from the calculated band-edge positions, and a high power conversion efficiency of 13.84% is also confirmed by spectroscopy limited maximum efficiency simulation. We estimate the time scale for electron–hole transfer and recombination times using a combination of non-adiabatic molecular dynamics and time-dependent density functional theory. A suitable e-h recombination time of 1.86 ns and electron (hole) transfer time of 331 (978) fs are obtained in the 2D MoS2/Hf2CO2 heterostructure, which is expected to ensure high photocatalytic efficiency. Therefore, the constructed MoS2/Hf2CO2 heterostructures provide a new example for the prediction of high-performance nano optoelectronic devices. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) van der Waals (vdW) heterostructures have attracted much attention due to their unique properties in photocatalysis, electronics, and energy storage. This work comprehensively analyzed the electronic properties and photocatalytic efficiency properties of 2D vdW MoS2/Hf2CO2 heterostructure by first-principles calculations and molecular dynamics simulation. An ideal band gap of 1.44 eV was found for visible light absorption. Meanwhile, a high solar-to-hydrogen efficiency of 17.14% is obtained from the calculated band-edge positions, and a high power conversion efficiency of 13.84% is also confirmed by spectroscopy limited maximum efficiency simulation. We estimate the time scale for electron–hole transfer and recombination times using a combination of non-adiabatic molecular dynamics and time-dependent density functional theory. A suitable e-h recombination time of 1.86 ns and electron (hole) transfer time of 331 (978) fs are obtained in the 2D MoS2/Hf2CO2 heterostructure, which is expected to ensure high photocatalytic efficiency. Therefore, the constructed MoS2/Hf2CO2 heterostructures provide a new example for the prediction of high-performance nano optoelectronic devices. [ABSTRACT FROM AUTHOR]