Ag/AgBr@MoS2 Nanocomposites for Sunlight-Driven Photocatalytic Water Remediation and Electrochemical Water Splitting

Janus-type Ag/AgBr nanoparticles (NPs) were prepared in situ onto the surface of MoS₂ exfoliated via low-energy bath sonication employing a biobased surfactant, choline deoxycholate ([Cho][Doc]). The [Cho][Doc] not only mediated the exfoliation of MoS₂ but also acted as a stabilizing and reducing agent under sunlight needed for the reduction and controlled growth of the Ag phase onto AgBr nanocrystallites. The dimensions as well as the extent of adherence of Ag/AgBr NPs onto MoS₂ in Ag/AgBr@MoS₂ nanocomposites (NCs) was affected by the form (monomeric or micellar) of [Cho][Doc], depending upon its concentration. The prepared NCs showed excellent photocatalytic activity toward water remediation with an exceptionally high rate constant under sunlight and appreciable electrochemical water splitting efficiency with stability up to at least 15 h for both the hydrogen evolution reaction and oxygen evolution reaction. In this way, a single-step, environmentally benign, and economically efficient method for preparing Ag/AgBr@MoS₂ NCs and their appreciable utility for water remediation under sunlight and electrochemical water splitting are established.