Reversible hydrogen storage in Y2C MXene under the influence of functional groups (F, Cl, OH)

Abstract

The hydrogen storage potential of the bare MXenes Y2C and terminated Y2CT2, where T is O, OH, or F, were studied using density functional theory (DFT). Hydrogen adsorption and desorption behaviors are simulated by ab initio molecular dynamic simulations. The interaction of the H2-molecules on the Y2C-family was investigated within the projected density of states. Only bare Y2C and Y2C(OH)2 provided Kubas-type interactions. The calculated maximum capacity of H2 in bare Y2C can reached up to 5.041 wt%, whereas the reversible capacity of H2 was up to 2.036 wt%. In Y2C(OH)2, the maximum capacity of H2 storage is 3.477 wt% and the reversible capacity was 1.769 wt%. This indicated that Y2C and Y2C(OH)2 are practical candidates for hydrogen storage applications.