Preparation Of Cadmium Sulfide–Based Photocatalytic Materials And The Study On The Hydrogen Performance Of Photocatalysis

With the accelerated development of economy and society,the air,water and soil pollution caused by industrialization has become increasingly serious,and energy and environmental problems have become global problems.Fossil fuels and industrial pollution emissions affect social development,and now we are starting to focus on clean,environmentally friendly renewable energy.Photocatalytic technology is the use of sunlight,widely used in energy production and environmental pollution control.Of course,hydrogen can be an environmentally friendly energy source,and researchers have begun to pay attention and research.Based on the morphology,their CdS by means of load and composite modification,respectively,the preparation of the Au/CdS?L?,Au/CdS?G?,Ag₃PO₄/CdS composite photocatalyst,light characterized all kinds of different material,photolysis of water hydrogen production experiments,the following conclusions:?1?by hydrothermal method,L-Asparagine as template agent,was synthesized by nano flake empty core ball formed from the accumulation of multi-level structure,through the deposition precipitation synthesis of Au/CdS photocatalytic materials.Because the special hollow sphere structure of Cd S increases the specific surface area and improves the capture efficiency of light.Due to the successful load of Au,the forbidden band width is reduced,which can be used as electron acceptor and transmission medium,which can inhibit the combination of electron and hole,thus improving photocatalytic performance.Photocatalytic experiments show that the hydrogen production efficiency of pure CdS is 0.856 mmolh^-1g^-1,and the hydrogen production efficiency of L-Asparagine is 4.995 mmolh^-1g^-1,and its hydrogen production is six times that of pure substance.When Au load is 1wt%,hydrogen production efficiency is highest at 64.173mmolh^-1g^-1,which is 75 times of pure CdS,and 13 times of that of CdS?L?.?2?with cadmium nitrate tetrahydrate and thiourea as raw materials,with mannitol as a kind of biological template agent,using the simple hydrothermal method was synthesized by the accumulation of nanoparticles into dispersed evenly,size uniformity of dendritic structure of Cd S.In the experiment,Au/CdS is synthesized by liquid phase precipitation,which can reduce the gap width and the special structure of CdS,which increases the photocatalytic activity of the semiconductor.By means of some characterization methods EDX and XPS can confirm that Au has been successfully loaded in a single quality form.It is shown that the increase of photocatalytic activity and Au's load is not linear.When the Au load is 1wt%,the hydrogen production efficiency is up to 64.173 mmolh^-1g^-1,which is 6 times of the Cd S?L?and 66 times of pure CdS,and its catalytic activity is the best.?3?through coprecipitation,Ag₃PO₄ and CdS were combined to form Ag₃PO₄/CdS?L?microporous structure.Ag₃PO₄ was used as an additive to effectively improve the photocatalytic performance of CdS.The molar ratio of Ag₃PO₄/CdS?L?was 0.7:3,which was the highest activity,and its hydrogen production efficiency reached 26.891 mmolh^-1g^-1,which was 27 times of CdS,and 5.4 times of Cd S?L?.There are two main reasons for the improvement of the activity of Ag₃PO₄/CdS?L?composite photocatalyst:on the one hand,the separation of photonic electrons and holes is promoted by different semiconductor composites,which influences the photocatalytic efficiency.On the other hand,the composite material is larger than the surface area,providing more active sites.