Efficient Visible-Light Photocatalytic MoS2/C3N4 Controllably Constructed in the Presence of Surfactants

A facile strategy was designed for the controllable fabrication of MoS2/g-C3N4 heterostructures in the presence of various anionic and cationic surfactants, including polyethyleneimine (PEI), hexadecyltrimethylammonium bromide (CTAB) and sodium dodecyl sulphate (SIDS), by in situ hydrothermal method. With the addition of cationic surfactant PEI, a special flower-sphere-like microstructure of MoS2/C3N4 composite has been fabricated, which exhibits the highest photoresponse and photocatalytic properties among all of the synthesized samples. The level of photocatalytic activity towards Rhodamine B degradation follows the order of MoS2/C3N4-PEI > MoS2/C3N4-CTAB > MoS2/C3N4 > MoS2/C3N4-SDS > MoS2. The photocurrent density of MoS2/C3N4-PEI composite is the highest and most stable among all the composites. Our study suggests that the photoelectroresponse depends strongly on the microstructure of MoS2/g-C3N4. The high photocatalytic performance was attributed to the intimate bonded heterostructure formed with PEI which reduces recombination losses of photogenerated charges at the MoS2/C3N4 interface.