Boron-substituted graphyne as a versatile material with high storage capacities of Li and H2: a multiscale theoretical study

摘要: Based on density functional theory (DFT), first-principles molecular dynamics (MD), and the grand canonical ensemble Monte Carlo (GCMC) method, we investigated boron substitution in aromatic rings of graphyne terms geometric electronic structures as well its bifunctional application including Li H2 storage. The calculated binding energies B-doped (BG) are significantly enhanced at two adsorptive sites compared to pristine graphyne, leading high lithiation potentials 2.7 V 6Li@1BG, even higher with 3.0 6Li@3BG. Thus, 6Li@1BG a capacity 1125 mA h g−1, which is much larger than other carbon materials, proposed be good anode material lithium-ion batteries. For further hydrogen storage 6Li@nBG, results show that it can steadily adsorb least 8H2 DFT, MD GCMC computations, excess gravimetric uptake 7.4 wt% ambient conditions, exceeding 2017 DOE target. Our multiscale simulations demonstrate chemical modifications two-dimensional very promising for lithium uptake.