In-situ reduction of Au(S2O3)23− for efficient recovery of gold with magnetically separable shell-core structured MoS2@Fe3O4 composite

Magnetic MoS 2 could be easily separated from water or solid suspensions. In this work, shell-core structured MoS 2 @Fe 3 O 4 composite was fabricated through hydrothermal method and used as catalyst for recovering gold-thiosulfate complex ions (Au(S 2 O 3 ) 2 3− ) in aqueous solution. The results suggested that MoS 2 @Fe 3 O 4 composite could effectively in-situ reduce Au(S 2 O 3 ) 2 3− to gold particles (Au 0 ) with an extremely high reduction capacity of 1541.1 mg/g; moreover, the gold loaded MoS 2 @Fe 3 O 4 could be easily collected using a magnetic separator. The mechanism of reducing Au(S 2 O 3 ) 2 3− to Au 0 was ascribed to the photoexcited electrons from MoS 2 @Fe 3 O 4 composite. More importantly, the incorporation of Fe 3 O 4 could effectively enhance the transferred efficiency of photoexcited electrons and accelerate separation of electrons-holes pairs. With great gold reduction capacity and magnetic recyclability , the MoS 2 @Fe 3 O 4 composite could be a promising material for recovering gold from leaching solutions.