Hydrothermal Synthesis Of Layered Tin Monoxide Semiconductor And Optical And Electric Propertics

Tin monoxide is a metastable metal oxide semiconductor material that forms a layered structure with the Sn-O-Sn sequence in the [001] crystal direction,and has the advantages of low cost,no toxicity,no pollution,and abundant natural content.Its Sn vacancy formation energy is low and it is easy to form p-type conduction,and has good semiconductor characteristics.At temperatures of 220? and below,Sn O can be stably present in the air.It is precisely because of its proper band gap structure and good stability that it is promising as an excellent photocatalytic material for environmental purification,so it can be used for photocatalytic degradation of organic pollutants;Sn O also has good performance in energy storage,and it has a high theoretical specific capacity,and has certain application value as a supercapacitor electrode material;Due to the structure of Sn O and its high carrier mobility,it can be used as a catalyst for electrochemical hydrogen evolution in a neutral electrolyte.The specific research contents are as follows:(1)Using the hydrothermal method and changing the alcohol-water ratio of the solvent in the reaction,the Sn O sample is prepared and it is studied that the effects of different proportions of solvent on the structure and morphology of the sample.Then the photocatalytic degradation of methyl orange was tested on the sample.The results show that different alcohol-water ratios have a very large effect on the morphology of the sample,which directly affects the photocatalytic performance of the sample.The thinner the sample is,the better the catalytic effect is.When the solvent is completely ethanol,the sample is the thinnest and has the highest utilization of photons,so it has the most excellent catalytic performance.(2)Three kinds of Sn O samples were prepared by hydrothermal method using different bases as reactants,and the effects of three reactants on the structure and morphology of the samples were investigated.It was found that the stronger the basicity of the reactants,the more regular the morphology of the formed samples.The sample was coated on the surface of the foamed nickel to make a supercapacitor electrode material and tested for its capacitive properties.The results show that the sample prepared using Na OH has a specific capacitance of 251.43 F/g at a density of 1 A/g,and the capacitance at a density of 20 A/g is maintained at 41.67%,while having the smallest internal resistance and the most Significant capacitance behavior indicates that it has the best supercapacitor performance among the three samples.(3)Changing the p H of the reaction solution,ultrasonic and organic-assisted hydrothermal methods are used to obtain the Sn O material,and then the sample is subjected to post-day treatment and analyze the effect of different p H and treatment methods on the morphology of the sample.It is found that the smaller the p H is,the larger the sample grows and the more surface pores is,the ultrasonic treatment can eliminate the corners of the sample and increase the surface porosity,and the hydrothermal treatment will only increase the fine particles on the surface of the sample.The sample was subjected to electrocatalytic hydrogen evolution test.It was found that the smaller the p H is,the better the effect of the sample is.The hydrothermal treatment inhibited the electrocatalytic activity of the sample,and the ultrasonic treatment was beneficial to the HER performance.The combination of these two methods can reduce the Tafel slope from 120 m V/dec to 100 m V/dec.