Nitrogen Doped γ‐Graphyne: A Novel Anode for High‐Capacity Rechargeable Alkali‐Ion Batteries

Abstract

High energy density is the major demand for next‐generation rechargeable batteries, while the intrinsic low alkali metal adsorption of traditional carbon–based electrode remains the main challenge. Here, the mechanochemical route is proposed to prepare nitrogen doped γ‐graphyne (NGY) and its high capacity is demonstrated in lithium (LIBs)/sodium (SIBs) ion batteries. The sample delivers large reversible Li (1037 mAh g−1) and Na (570.4 mAh g−1) storage capacities at 100 mA g−1 and presents excellent rate capabilities (526 mAh g−1 for LIBs and 180.2 mAh g−1 for SIBs) at 5 A g−1. The superior Li/Na storage mechanisms of NGY are revealed by its 2D morphology evolution, quantitative kinetics, and theoretical calculations. The effects on the diffusion barriers (Eb) and adsorption energies (Ead) of Li/Na atoms in NGY are also studied and imine‐N is demonstrated to be the ideal doping format to enhance the Li/Na storage performance. Besides, the Li/Na adsorption routes in NGY are optimized according to the experimental and the first‐principles calculation results. This work provides a facile way to fabricate high capacity electrodes in LIBs/SIBs, which is also instructive for the design of other heteroatomic doped electrodes.

Converting CO2 into an Oxygenated Alkynyl Carbon Material with High Electrochemical Performance through a Mechanochemical Reaction with CaC2

“…The weak alkynyl stretching vibrations may be attributed to their high structural symmetry in the OACM. , Notably, these oxygenated groups can improve the hydrophilicity (Figure S4), which is beneficial for its aqueous electrochemical applications . Furthermore, the solid-state 13 C NMR spectrum of the OACM (Figure d) reveals the existents of the quaternary carbon ether (74.1 ppm), ketone carbonyl (192.1 ppm), and sp -hybridized carbon (88.6 ppm), indicating the formation of the alkynyl-linked oxygen carbon chains in the resultant OACM. Meanwhile, it is found that the OACM sample has strong electrical conductivity during testing, which resulted in a lot of peak noise in the NMR spectrum and also suggested its potential semiconductor properties.…”

Artificial N-doped Graphene Protective Layer Enables Stable Zn Anode for Aqueous Zn-ion Batteries

“…FT-IR and XPS were carried out to demonstrate the kinds of functional groups and the chemical valence states in NGO@Zn. As shown in Figure e, the peaks at around 2916.72, 1550.32, and 1165.12 cm –1 can be attributed to C–H, CC, and C–N, respectively . In contrast, the peaks of the C–N functional groups on the surface of the NGO become stronger after N-doping, implying the successful introduction of nitrogen into the RGO material (Figure S4).…”

“…As shown in Figure 1e, the peaks at around 2916.72, 1550.32, and 1165.12 cm −1 can be attributed to C−H, CC, and C−N, respectively. 39 In contrast, the peaks of the C−N functional groups on the surface of the NGO become stronger after N-doping, implying the successful introduction of nitrogen into the RGO material (Figure S4). Figure 1f displays the peaks of N 1s, which could be divided into pyridinic N (398.4 eV), pyrrolic N (400.4 eV), and graphitic N (401.4 eV).…”

Graphyne Nanotubes as Promising Sodium-Ion Battery Anodes

“…In 2019, they further reported well-defined hydrogen-substituted graphyne (HsGY) with a reversible capacity of 600 mAh/g at a current density of 100 mA/g [37]. In 2020, Cui's group synthesized N-doped γ-graphyne (NGY) to deliver a large reversible storage capacity of 570.4 mAh/g at 100 mA/g, accompanied by excellent rate capability [39]. Through a first principles investigation, Xu et al determined that graphyne and graphdiyne have not only high Na storage capacity, but also strong diffusions because of the existence of large sized pores [40].…”