“…Zhang et al noticed the improved degradation rate of a ZnS-Ag 2 S composite relative to that of bare ZnS [21]. Similarly, novel ZnS composites such as TiO 2 /ZnS [22], ZnS/CdS [23], ZnS/ZnO [24], ZnS-CuS [25], and ZnS-CoFe 2 O 4 [26] have been synthesized for prominent applications. Among these, ZnS-Ag 2 S is a well-known heterostructure for its characteristic structural, optical and photoluminescence (PL) properties [27][28][29].…”