Regulation of the degree of hydrogenation and electrochemical properties of graphene generated by electrochemical cathodic exfoliation by using different solvents

Abstract

Hydrogenated graphene has attracted much attention because its properties can be tuned by varying the degree of hydrogenation. In this work we adjusted the degree of hydrogenation of hydrogenated graphene by using different solvents in the electrochemical cathodic exfoliation process. Interestingly, the graphene obtained by exfoliation in different solvents showed a range of electrochemical performances. The characterization data indicated that the highest level of hydrogenation was observed with the sample produced in N,N-dimethylformamide (G-DMF). Moreover, the G-DMF also showed superior electrochemical performance in terms of electron-transfer rate and sensitivity towards ascorbic acid, which is attributed to the fact that it has most catalytic active defect sites, induced by the high degree of hydrogenation. In addition, the sample produced in propylene carbonate (G-PC) showed the lowest density of defects, while the sample produced in dimethyl sulfoxide (G-DMSO) did not appear to have any electrochemical benefits. Overall, the results suggest a route to the scalable production of graphene with a tunable degree of hydrogenation using a facile and simple strategy.