Three layered sulfides ACuZnS 2 (A = K, Rb, Cs) were synthesized solvothermally by employing excess sulfur as a mineralizer. The photoelectric response experiments show that these compounds exhibit photoelectric response performance. Photocatalytic experiments reveal they have excellent photodegradation on methylene blue (MB). [Display omitted] • Three layered sulfides ACuZnS 2 (A = K, Rb, Cs) were synthesized solvothermally by employing excess sulfur as a mineralizer. • These isostructural compounds contain anionic [CuZnS 2 ] n n– layers composed of MS 4 (M = Cu/Zn) tetrahedra. • The photoelectric response experiments show that these compounds exhibit photoelectric response performance. • Photocatalytic experiments reveal they have excellent photodegradation on methylene blue (MB). By employing excess sulfur as a mineralizer, three quaternary hetero-transition metal sulfides KCuZnS 2 (1), RbCuZnS 2 (2), and CsCuZnS 2 (3) were synthesized under solvothermal conditions. These isostructural compounds crystallize in tetragonal space group I 4/ mmm and contain anionic [CuZnS 2 ] n n– layers composed of MS 4 (M = Cu/Zn) tetrahedra. The band gap values suggest that these compounds are semiconductors. The photoelectric response experiments show that these compounds exhibit photoelectric response performance. In addition, photocatalytic experiments reveal they have excellent photodegradation on methylene blue (MB). [ABSTRACT FROM AUTHOR]