The carbon-hydrogen composite systems of para-hydrogen (p-H-2) sandwiched by a couple of graphene sheets have been investigated by means of path integral centroid molecular dynamics simulations at 17 K. It has been shown that sandwiched hydrogen is liquid-like but p-H-2 molecules are preferably adsorbed onto the graphene sheets because of attractive graphene-hydrogen interaction. The diffusion coefficient of p-H-2 molecules in the direction parallel to the graphene sheets is comparable to that in pure liquid p-H-2. There exists a characteristic mode of 140 cm (1) of the p-H-2 molecules, attributed to adsorption-binding motion perpendicular to the graphene sheets. (C) 2016 Elsevier B.V. All rights reserved.