| Highly crystalline ZnS nanoparticles was prepared by there different methods, i.e.,hydrothermal method (HTM), solvent-thermal method (STM) and chemical synthesismethod (CSM). The photocatalytic activity for degradation of methylene blue wasinvestigated under UV and visible-light irradiation, respectively. The primary resultsdemonstrated that the synthesized powder of ZnS prepared by hydrothermal method wasbetter than the other two. So ZnS prepared by hydrothermal method was our choice. ZnSdoped aluminophosphate molecular sieves were prepared by hydrothermal synthesisstarting from phosphoric acid and pseudo-boehmite as the source of phosphorus andaluminum, using triethylamine as organic template, and in-situ mixed with ZnS. Then, itwas crystallized at a certain temperature and time. The product was characterized byXRD,SEM,FT-IR,UV-Vis-DRS,XPS,TG,BET and its photocatalytic activities wasevaluated by the photodegradation of rhodamine B under ultraviolet irradiation and thephotodegradation of methylene blue under visible light. At the same time, the impact onvisible light degradation of methylene blue was studied under the different conditions:different mass of adulterat, different pH, different catalyst amount, and different pH inthe dye. The primary results showed that, the sample had the same structure ofaluminophosphate molecular sieves, the doped ZnS might enter the framework of themolecular sieves; it also revealed well photocatalytic activity of samples on rhodamineB and methylene blue. The deeolourization rate of the rhodamine B solution was 88.7%with ZnS/APO under UV illumination,its mineralization rate was 36.7%, if illumining330min,the date was 92.6%. The decolourization rate of the methylene blue solution was97.5% with ZnS/APO under visible light, its mineralization rate was 18.7%, ifillumining 24h, the date was 90%.The photocatalytic activity of samples on methyleneblue was to some extent affected by the different preparation and photocatalytic reactionconditions.
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