Preparation, Structural Regulation And Photocatalytic Properties Of Zinc Sulfide Based Nanomaterials

Hydrogen as one kind of clean and efficient energy has been receiving increasing attention in addressing energy shortage issue.Converting the richest solar energy into a storageable chemical energy is an approach to solve energy problems of which using solar energy to catalyze water splitting into hydrogen is the most effective way,therefore,the development of effective hydrogen evolution catalyst has become a hotspot.ZnS is a typical transition metal sulfide that has been extensively studied in the field of photocatalysis due to the low cost of raw materials,suitable bandgap position for photocatalytic water splitting and fast migration rate of charge carriers.Thus,the development of efficient photocatalytic materials based on ZnS is of great significance.In this paper,we improved the photocatalytic hydrogen production activity of ZnS by tuning its microstructure and combining with MoS2.Moreover,the response range to light was widened into visible light through constructing nanocomposites.The main contents are as follows:1.Synthesis of small size ZnS hollow nanospheres by the assist of biomass gelatin.The microstructure includes voids size,shell thickness and grain size of ZnS nanospheres can be regulated by adjusting the amount of gelatin,hydrothermal reaction time and temperature.The ZnS nanospheres showed good photocatalytic activity and excellent stability under Pt-free condition.The best activity can reach 339 ?mol/h.2.MoS2 is a widely studied non-Pt photocatalytic hydrogen production cocatalyst.First,small size phosphomolybdic acid was choosen as molybdenum source,2-mercaptobenzimidazole was selected as sulfur source,utilizing the slow release process of sulfur,we synthesised MoS2 with sheet-like structure.ZnS hollow nanospheres and MoS2 were mixed briefly before used in photocatalytic water splitting.When the mass fraction of MoS2 is 5%,the photocatalytic activity achieved the maximum value about 638 ?mol/h.3.ZnS/CdS hollow composites which prepared by simple cation exchange method were applied in the photocatalytic water splitting test.The microstructure of the hollow spheres changed with the difference of ion exchange degree and the highest photocatalytic activity of hydrogen evolution can reach 62.2 ?mol/h.