An in-situ growth approach to 2D MoS2-2D PbS heterojunction composites with improved photocatalytic activity

The advantage of 2D-2D heterojunction over 2D-0D and 2D-1D heterojunction is that it has larger interface area, which results in the shorter migration distance of photo-induced charge carriers, and can therefore separate the electron-hole pairs more effectively. In this work, to form 2D-2D heterojunction , PbS nanosheets were grown in situ on 2D MoS 2 layers via. solvothermal process. The formation of 2D MoS 2 -2D PbS composites has been confirmed by XRD , Raman, TEM , and EDS analysis . The area of PbS nanosheets attached on MoS 2 can be controlled by changing the concentration of PbS precursor in reaction solution. Compared with pristine MoS 2 , MoS 2 -PbS composites showed improved light absorption property and enhanced photocatalytic ability using methylene blue as the target of degradation. The optimized composite displayed a photocurrent 5 times higher than that of pristine MoS 2 .