Chlorinated Graphene via the Photodecomposition of Metal Chlorides

Searching for a facile and sustainable chlorination method to modify graphene has drawn tremendous attention due to the modulation of its electronic property and surface chemistry. In contrast to the previously developed Cl₂ photochlorination method via Cl radicals, present work found that the photodecomposition of metal chlorides under UV light irradiation was able to chlorinate graphene taking into account both appropriate Cl contents and high carrier mobility. Field-effect transistor proved that the mobility was around 345.5 cm² V^-1 s^-1 when introducing 4.3 atom % Cl dopants. Raman proved that UV irradiation resulted in structural defects to favor the mass transport in electrochemical reactions. Chlorinated vertically oriented graphene nanosheets on carbon cloth exhibited improved oxygen evolution reaction performance in comparison to that of pristine graphene. The specific electrochemical active area and charge transfer analysis indicated that Cl-doping was favorable for the exposure of active sites and fast electron transport, thus driving the electrochemical kinetics by virtue of a small Tafel value (59 mV dec^-1). The direct growth of graphene nanosheets on carbon cloth endowed the free-standing film with robust durability. The present work opens a new avenue for the chlorinated graphene considering all merits for electrochemical activities and will provide promising candidates for application in energy storage and conversion fields.