Acoustodesorption of alkali metals and halogens from single-layer graphene: Simple estimates

An increase in the thermodesorption probability under deformation wave, i.e., acoustodesorption, was estimated for alkali metal and halogen atom adsorption on single-layer graphene. To this end, first, a simple analytical expression for the adsorption energy is proposed. Second, using the previously developed adsorption M-model, the effect of the time-variable hydrostatic compression-tension of a graphene sheet on the adatom charge and adsorption energy is considered. It is shown that the derivative of the adsorption energy with respect to the strain is an order of magnitude higher for halogens than for alkali metals, and the desorbed atom flux is maximum for iodine desorption. To study the dependence of the adatom charge on the strain, the low-energy approximation (LEA) is also used. In this case, LEA estimates for alkali metals show satisfactory agreement with the results of the M-model. Within the LEA, it is demonstrated that uniaxial and hydrostatic deformations lead to order-of-magnitude identical effects.