Chlorinated Graphene via the Photodecomposition of Metal Chlorides

Abstract

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.

Direct Growth of CNTs@CoSxSe2(1−x) on Carbon Cloth for Overall Water Splitting

“…These results were consistent with previous reports that cobalt oxides or CoOOH formed in situ contains high-valent Co III or Co IV ions, whicha re considered to be the true active speciesf or adsorbing the key OOH* intermediate to trigger the OER process. [30] Meanwhile, the graphitic Ni nC NTsc ould provide electrons to the p-conjugated system of CNT,t hat is, n-type doping, and thus enhance H* adsorption on negatively polarized domains to accelerate the HER. [13,28] After OER, the peak at approximately 168.9 eV for SO x became dominant as ar esult of surface oxidation during the OER process.…”

“…It has been reported that pyridinic-N-induced p-typed oping of carbon can providea ctive domains for OER. [30] Meanwhile, the graphitic Ni nC NTsc ould provide electrons to the p-conjugated system of CNT,t hat is, n-type doping, and thus enhance H* adsorption on negatively polarized domains to accelerate the HER. In addition, the coupling effect between CoS x Se 2(1Àx) and N-doped CNT would synergistically improve the activity for both HER and OER.…”