Influence of SnS buffer layers on the growth and properties of nanostructured Bi2S3 films by chemical bath deposition

Nanostructured Bi2S3 films that comprise rod-shaped particles were prepared on glass substrates by chemical bath deposition. When a SnS buffer layer was deposited on the substrate before the deposition of the Bi2S3 films, the homogeneity and the adhesion of the prepared Bi2S3 films are largely improved. Furthermore, when the buffer layer is inserted, the electrical conductivity of the films increases from lower than 10−6 Ω−1 cm−1 to 4 × 10−5 Ω−1 cm−1, and the average optical absorption in the band between 350 nm and 800 nm increases from around 41% to around 76%. The reason for these results is considered to be that the SnS layer can promote the nucleation of the Bi2S3 on the substrate.