Electrical magnetotransport properties of chlorinated CVD graphene

We report on electrical resistivity, magnetoresistance, and Hall-effect experiments in single-layer CVD graphene submitted to photochlorination. The resistivity and the ordinary Hall effect reveal a strong hole doping due to Cl adsorption. Intrinsic disorder of the as-grown system as well as that produced in the chlorination process lead to weak-localization effects, observed in the low-temperature magnetoresistance. The theoretically predicted regime where intervalley scattering fully restores the usual negative magnetoresistance is observed in a freshly chlorinated sample. Also observed are time-dependent effects in the electrical transport properties of the functionalized CVD-graphene samples due to a progressive loss of adsorbed Cl.