| With the continuous development of society,the demand for new material with multiple functions increases rapidly.Due to the nature of possessing organic and inorganic components,inorganic-organic hybrid materials have received wide attention from all walks of life.The organic composition provides strong flexibility and inorganic component enhances the degree of mechanical strength and heat resistance.Therefore,the organic-inorganic hybrid materials have a great prospect in various areas,such as electronics,optics,gas storage,new energy and biological sensorIn recent years,molecular layer deposition(MLD)technique has become a kind of attractive preparation methods for organic-inorganic hybrid materials.MLD has various advantages,including three dimensional conformality,large area uniformity,easy control of molecular chain segments and the functional groups.Now we have developed some inorganic-organic complex compound systems.However,the organic precursors of MLD have rich selectivity.We can design a variety of inorganic-organic complex compounds by choosing different reactive functional groups and organic segment with different length.Therefore,the MLD growth systems we master are just a few of the inorganic-organic complex compound family.In addition,some MLD growth mechanisms are unclear yet.Thus,the research on the growth of the new material system needs further exploring.Moreover,MLD technique has prominent advantages in the field of 3-D nanostructured electrode fabrication for high performance energy storage devices.The report of MLD applied in the field of electrochemical energy storage is relatively rare and the related study is still in the early stageTherefore,this thesis lays emphasis on the research of MLD growth process of the new inorganic-organic hybrid compounds,and explores the application of inorganic-organic complex compound in charge trapping memory devices and supercapacitors.In this paper,the MLD growth process of Ti-based maleic acid complex was developed,and the related growth mechanism,the charge trapping ability of the Ti-based maleic acid hybrid film was studied.This paper also uses MLD technique to deposit Al-based fumaric acid hybrid films to prepare core-shell structure of carbon cloth@three-dimensional porous carbon,which can be directly used as electrode in supercapacitors.The main achievements are summarized as follows:1.The growth process of Ti-based maleic acid hybrid film has been studied systematically and discussed with Ti-based fumaric acid hybrid film system.Similar to most of the MLD systems,the deposition rate of the Ti-based maleic acid hybrid films decreased from 1.42 A/cycle of 140? to 0.16 A/cycle of 280?.However,the deposition temperature has little effect on the chemical composition and structure of the Ti-based maleic acid hybrid films.The surface is smooth and the surface roughness is only 0.18 nm.The results of XPS and in situ QCM show that the product is the complex of TiO2 and Ti-based maleic acid,and the existence of TiO2 makes Ti-based maleic acid hybrid film more stable in air.After one year's exposure,the film composition and structure have no change.We use the Ti-based maleic acid hybrid film as the charge trapping layer,and do some research on the performance of the corresponding charge trapping memory device.We find that storage window is proportional to the thickness of the hybrid film.The sample of the 7 nm under the scanning voltage of±16 V can achieve maximum storage window of 11.04 V,and show a great write/erase speed and fatigue property.In addition,we found that using Ti-based maleic acid hybrid film as the charge storage layer has better performance than Ti-based fumaric acid hybrid films,attributing to the complex system of TiO2 and Ti-based maleic acid hybrids in TiCl4-maleic acid system.However,the performance of the device decreased slightly after a period of time in the air,and the data retention and stability need to be further imporoved.2.Al-based fumaric acid hybrid films can perfectly coat the fiber surface of carbon cloth by MLD.After high temperature annealing treatment and corrosion,carbon cloth was parceled with three-dimensional porous carbon.Through a series of component structure characterization,we found that the 600? is the best annealing temerature.Raman spectra show that graphitizing degree of the sample with the 600? annealing is highest,and the specific surface area is around 374.22 m2/g,and the pore size is mainly distributed in microporous under 2 nm range.The carbon cloth@three-dimensional porous carbon can be directly used as supercapacitor electrode materials.And the electrochemical results are consistent with microstructure characterizations,confirming that the three-dimensional porous carbon electrode material acquired under 600? has the best performance.When the current density is 1 A/g,the specific capacitance of electrode is as high as 195.2 F/g,the electrode material is provided with small charge transfer and ion diffusion resistance.Therefore,it has the extremely good rate ability,when the current density increases 20 times to 20 A/g,it remains around 81.1%of initial capacitance.In addition,when cycled at the current density of 20 A/g,the capacitance can be maintained at about 98.45%after 10,000 cycles of charging and discharging,exhibiting an excellent cyclic stability. |
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