Copper-doped flower-like molybdenum disulfide/bismuth sulfide photocatalysts for enhanced solar water splitting

A facile synthesis approach to fabricate Cu-doped MoS2/Bi2S3 (Cu-MoS2/Bi2S3) photocatalysts is reported. The photocatalyst samples with varying amounts of Cu are applied in the photocatalytic splitting of water to produce H2 under the irradiation of simulated solar light. The Cu-MoS2/Bi2S3 photocatalysts with an optimum Cu loading of 20 mol% exhibited high photocatalytic performance, achieving a total H2 yield of 32.4 μmol/h after 6 h of reaction. The photoactivity of the Cu-doped sample was shown to have risen more than 40% than that of pure MoS2/Bi2S3. The improved performance is attributed to the impurity states generated within Cu-doped MoS2, which serve as trapping sites for photogenerated electrons. The effective charge transfer mechanism achieved was evidenced by photoelectrochemical measurements. Based on the experimental results obtained, a plausible mechanism for the photocatalytic process associated with Cu-MoS2/Bi2S3 was proposed.