1H NMR study of hydrogen stored in activated carbon powder prepared by mechanical milling

► Three hydrogen components were observed in hydrogenated milled activated carbon by 1H NMR. ► One of three hydrogen components was very unstable. ► Each hydrogen component had high and low molecular mobility. ► These components were assumed the physisorbed hydrogen in the pores, the chemisorbed hydrogen to dangling bonds and the adsorbed hydrogen weakly onto the surface of activated carbon.