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Lithium (Li) is a promising anode material for all‐solid‐state Li metal batteries (ASSLMBs) due to its high energy density. However, the interface incompatibility of Li/solid electrolyte and uneven Li deposition induces the penetration of Li dendrites. Herein, a multifunctional rich‐LiF/Mg artificial solid electrolyte interphase (SEI) layer is constructed from a MgF2‐PVDF‐HFP film to passivate the Li anode and achieve effective inhibition of Li dendrites. Notably, the triggered LixMg alloys rivet the Li6PS5Cl (LPSCl) electrolyte and Li anode together well, producing satisfactory interface contact and reducing overpotential. The mechanism of LiF and LixMg alloys to enhance the stability of the Li/LPSCl interface is further elucidated by density functional theory (DFT). Moreover, the synergistic interaction of LiF with high interfacial energy and LixMg alloys with low diffusion barrier promotes uniform deposition of Li during plating/stripping and structural stability. Therefore, the modified Li‐symmetric cell exhibits ultra‐high critical current density (2.0 mA cm−2) and considerable cyclic stability (more than 1000 h at 0.5 mA cm−2). Remarkably, NCM//LPSCl//3% MgF2‐PVDF‐HFP@Li ASSLMBs exhibit considerable long‐term cycle stability (86.9% capacity retention after 100 cycles at 0.2 C). This work highlights the critical role of the intermediate passivating layer in mitigating side reactions and preventing Li penetration. [ABSTRACT FROM AUTHOR]

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]

Electrocatalysts for the oxygen evolution process must be both active and stable in order to make hydrogen from water using renewable power. Nitrogen‐doped carbon layer coated cobalt manganate particles were synthesized on carbon cloth using calcination method. The catalysts exhibited small particle sizes and graphitized carbon layer that covered the cobalt manganate, facilitating electron flow. Moreover, the nitrogen‐doped carbon layer enhanced the oxygen evolution reaction (OER) rate by reducing the potential required for surface reconstruction and optimizing electron distribution on the cobalt manganate surface. This electrocatalyst demonstrated a current density of 100 mA/cm2 at 1.56 V vs. RHE. Thus, this electrocatalyst shows promise as a novel OER catalyst for water oxidation in acidic aqueous solutions. [ABSTRACT FROM AUTHOR]

Due to the upstream pressure of lithium resources, low-cost sodium-ion batteries (SIBs) have become the most potential candidates for energy storage systems in the new era. However, anode materials of SIBs have always been a major problem in their development. To address this, V 2 C/Fe 7 S 8 @C composites with hierarchical structures prepared via an in situ synthesis method are proposed here. The 2D V 2 C-MXene as the growth substrate for Fe 7 S 8  greatly improves the rate capability of SIBs, and the carbon layer on the surface provides a guarantee for charge-discharge stability. Unexpectedly, the V 2 C/Fe 7 S 8 @C anode achieves satisfactory sodium storage capacity and exceptional rate performance (389.7 mAh g -1  at 5 A g -1 ). The sodium storage mechanism and origin of composites are thoroughly studied via ex situ characterization techniques and first-principles calculations. Furthermore, the constructed sodium-ion capacitor assembled with N-doped porous carbon delivers excellent energy density (135 Wh kg -1 ) and power density (11 kW kg -1 ), showing certain practical value. This work provides an advanced system of sodium storage anode materials and broadens the possibility of MXene-based materials in the energy storage., (© 2023 Wiley-VCH GmbH.)

With the increasing demand for renewable energy and clean energy, photocatalysis is considered an economical and feasible source of energy. In this work, we select two-dimensional (2D) materials of X 2 CT 2 (X = Cr, Hf, Mo, Sc, Ti, Zr; T = Cl, F, O, OH), Mxene, and MS 2 (M = Mo, W) to form 20 systems of 2D van der Waals (vdW) heterostructures. We establish five screening steps, and the 2D Mo 2 CF 2 /WS 2 vdW heterostructures meet all the screening conditions. Mo 2 CF 2 /WS 2 is a type II semiconductor with a band gap of 1.58 eV, proper band edge position and high solar-to-hydrogen efficiency (17.15%) and power conversion efficiency (23.4%). An excellent electron-hole recombination time of 21.2 ps and electron (hole) migration time of 149 (265) fs are obtained in the 2D Mo 2 CF 2 /WS 2 vdW heterostructure. In addition, the calculation results of Gibbs free energy show that a hydrogen reduction reaction and water oxidation reaction can proceed smoothly under the driving of photogenerated holes.