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[Display omitted] • Amorphous Al 2 O 3 in porous carbon anchored on carbon cloth was first fabricated. • The composite was investigated as a multifunctional interlayer for Li-S batteries. • The Li-S cells with high sulfur-loading exhibited superior cycling stability. • The Li-S cells exhibited excellent rate capability. • The amorphous Al 2 O 3 in porous carbon can effectively suppress the LPS shuttle effect. To realize practical applications of lithium-sulfur batteries, rational strategies have to be applied to overcome obstacles such as the shuttle effect and sluggish reaction kinetics of soluble long-chain lithium polysulfides (LPS). In this work, highly electrocatalytic active amorphous Al 2 O 3 uniformly dispersed in porous carbon (Al 2 O 3 /C) anchored on carbon cloth (CC) was successfully fabricated. The resultant flexible Al 2 O 3 /C@CC was used as an independent interlayer for Li-S batteries, demonstrating strong physical confinement and chemical binding ability for LPS, as well as high catalytic activity for LPS conversion kinetics due to a synergistic effect of 3D conductive network, amorphous nature of Al 2 O 3 /C, porous structure and abundant active sites. The cells with such interlayer exhibit high specific capacity, superior cycling stability and rate capability, 903 mAh/g at 0.2C after 100 cycles and 810 mAh/g at 1.0C after 300 cycles can be achieved, moreover, 741 mAh/g can still be retained at a high rate of up to 5.0C. By contrast, Al-MOF grown on carbon cloth (Al-MOF@CC) exhibits limited performance improvement due to poor electrical conductivity, low structure stability, as well as limited ion diffusion rate and weak Lewis acid-base interactions due to lack of open channels. [ABSTRACT FROM AUTHOR]

The growth of dendrites and the hydrogen evolution reaction pose significant challenges to the development of Zn metal aqueous batteries as a promising solution for energy storage. Herein, trisodium nitrilotriacetate (Na3NTA) as an electrolyte additive is shown to improve the reversibility of the zinc plating–stripping process. NTA3− anions possess the potential not only to substitute water molecules in the solvation sheath of Zn2+ ions but also to construct a zincophilic electrolyte/Zn anode interface and suppress the activity of water molecules for stabilizing the Zn anode. The introduction of Na3NTA can effectively suppress side reactions arising from active water decomposition and simultaneously lead to the formation of a well‐defined (002) texture structure. As a result, a Zn||Zn symmetric cell with a modified electrolyte demonstrates a lifespan of up to 3000 h at a cutoff capacity of 1 mA h cm−2. Furthermore, a Zn||V2O5 full cell exhibits an enhanced capacity retention of 83.2% even after undergoing 8000 cycles. No noticeable dendrites are observed even after long cycles in both symmetric and full cells. Due to the cost‐effective material and ease of fabrication of the Na3NTA additive, this electrolyte strategy may promote the industrial application of aqueous zinc ion batteries. [ABSTRACT FROM AUTHOR]

An effective avenue to develop nonmetal atoms doped 2D Ti 2 CO 2 catalysts with integrating DFT calculations, nonmetal single atom valence electron number and bader electron transfer coupled electron descriptor and electronic structure validations. [Display omitted] • We implanted 14 kinds of nonmetal atoms into Ti 2 CO 2 to improve the HER activity. • Good HER catalytic activity and conductivity could be simultaneously achieved. • Coupling descriptor could accurately predict HER catalytic activity trends. • High-throughput computing combination descriptor is an effective avenue to develop HER catalysts. 2D MXenes, with large surface area, good conductivity, adjustable hydrophilic and varies surface functional groups, are potential catalyst for hydrogen evolution reaction (HER). In this work, 14 kinds of nonmetal (NM) single atom doped 2D Ti 2 CO 2 catalysts were screened by DFT method. It was found that the surface doping of nonmetal single atom can effectively promote the HER activity of Ti 2 CO 2. Among them, Ti 2 CO 2 with rich fluorine termination groups realizing efficient electrocatalytic HER has been successfully verified by recent experiments. Through the analysis of electronic structure, it is found that nonmetal single atom valence electron number and bader electron transfer coupled electron descriptor is suitable to accurately predict the trend of 2D NM-Ti 2 CO 2 catalytic activity for HER. The large-scale screening of this work and the mechanism analysis of nonmetal single atom surface doping enhanced of 2D Ti 2 CO 2 HER activity not only provide a database reference for the experimental synthesis of NM-MXenes HER catalyst, but also provide a electronical mechanism guidance for the extensive design of new NM- MXenes materials. [ABSTRACT FROM AUTHOR]

As a typical two-dimensional (2D) MXene, Ti3C2O2 has been considered as a potential material for high-performance hydrogen evolution reaction (HER) catalyst, due to its anticorrosion and hydrophilic surface. However, it is still a challenge to improve the Ti3C2O2 surficial HER catalytic activity. In this work, we investigated the HER activity of Ti3C2O2 after the surface was doped with S, Se, and Te by the first principles method. The results indicated that the HER activity of Ti3C2O2 is improved after being doped with S, Se, Te because the Gibbs free energy of hydrogen adsorption (ΔGH) is increased from −2.19 eV to 0.08 eV. Furthermore, we also found that the ΔGH of Ti3C2O2 increased from 0.182 eV to 0.08 eV with the doping concentration varied from 5.5% to 16.7%. The HER catalytic activity improvement of Ti3C2O2 is attributed to the local crystal structure distortion in catalytic active sites and Fermi level shift leads to the p-d orbital hybridization. Our results pave a new avenue for preparing a low-cost and high performance HER catalyst. [ABSTRACT FROM AUTHOR]

2D MXenes have been found to be one of the most promising catalysts for hydrogen evolution reaction (HER) due to their excellent electronic conductivity, hydrophilic nature, porosity and stability. Nonmetallic (NM) element doping is an effective approach to enhance the HER catalytic performance. By using the density functional theory (DFT) method, we researched the effect of nonmetallic doping (different element types, variable doping concentrations) and optimal hydrogen absorption concentration on the surface of NM-Ti3C2O2 for HER catalytic activity and stability. The calculation results show that doping nonmetallic elements can improve their HER catalytic properties; the P element dopants catalyst especially exhibits remarkable HER performance (∆GH = 0.008 eV when the P element doping concentration is 100% and the hydrogen absorption is 75%). The origin mechanism of the regulation of doping on stability and catalytic activity was analyzed by electronic structures. The results of this work proved that by controlling the doping elements and their concentrations we can tune the catalytic activity, which will accelerate the further research of HER catalysts. [ABSTRACT FROM AUTHOR]

Tungsten carbide (WC) has received widespread attention as a new type of nonprecious metal catalyst for hydrogen evolution reaction (HER). However, it is still a challenge to improve the surface HER catalytic activity. In this work, the effects of different nonmetallic dopants on the catalytic activity and stabilities of WC (0001) surface for HER were studied by first principles methods. The effects of different types of non-metal (NM = B; N; O; P and S) and doping concentrations (ni = 25–100%) on HER catalytic activity and stability were investigated by calculating the Gibbs free energy of hydrogen adsorption (∆GH) and substitution energy. It was found that the catalytic performance can be improved by doping O and P non-metallic elements. Especially, the ∆GH with P doped is −0.04eV better than Pt (−0.085 eV), which is a potential ideal catalyst for HER. Furthermore, the electronic structure analysis was used to explore the origin of the regulation of doping on stability and catalytic activity. The results show that nonmetallic doping is an effective strategy to control the catalytic activity, which provides theoretical support for the future research of HER catalysts. [ABSTRACT FROM AUTHOR]