Heterogeneous nucleation on defects in MoS2 nanostructures as a proxy for assessing active sites for hydrogen production

In the present work, we applied heterogeneous nucleation of gold nanoparticles to assess the density of defects on MoS2 nanostructures presenting different morphologies and surface areas. The use of L-cysteine resulted in the formation of flower-shaped MoS2 nanostructures with a diameter of about 300 nm and petals measuring around 30 nm. In contrast, when 3-mercaptopropionic acid was employed, it led to the formation of large agglomerates, here referred to as nanoclouds, with a diameter of approximately 500 nm. The nucleation of gold nanoparticles on defect sites of MoS2 suggested that MoS2 obtained from 3-mercaptopropionic acid has a higher content of active sites for hydrogen production compared to MoS2 obtained from L-cysteine.