Preparation Of Nano Hollow Spherical TiO₂ And Their Photoelectric Performance Research Based On Experiment And Parameterization

Titanium dioxide?TiO₂?has many kinds of structures,and anatase and rutile have been widely used in the photoelectric properties.However,researchers have ignored the photoelectric properties of monoclinic crystal titanium dioxide?TiO₂-B?.Compared with the two structures,TiO₂-B has higher photoelectric activity and surface structure,and it may be one of the candidates for optoelectronic materials.Currently,nano hollow spheres TiO₂ was synthesized based on template preparation,and the prepared hollow spheres have ball diameters 100 nm.The method draws into the organic matter,and organic matter can cause environmental pollution.At the same time,the prepared hollow sphere diameter is also larger.In addition,nano titanium dioxide doped with other elements can change their optical properties,and the researchers often study effects of one or several ions on the doping of TiO₂ at different concentrations,but rarely research the effects of different ions at the same concentration.For doping ions in the same concentration,some micro factors can affect photocatalytic properties of titanium dioxide such as doping ions,coordination number,ionic radius,valence electron structure,band gap of TiO₂.The paper mainly studied the content:1.Using titanium sulfate as raw materials,nano hollow spheres monoclinic TiO₂?TiO₂-B?are synthesized based on hydrothermal-coprecipitation method.The average diameters of the prepared structures are 10nm-18 nm,and the wall thicknesses are 3-5 nm.Compared with the conventional template process,the sizes of nano hollow spheres not only are significantly smaller?the diameter of the hollow sphere is round 100 nm using traditional template method?,but aso draw into the organic matter rarely.In the premise of excellent performance,it improves the safety and protection of the environment.Using the kirkendal effect,oriented attachment mechanism,Gibbs Curie Wulff crystal growth theory and the Ostwald rules as the theoretical basis,hollow sphere TiO₂-B is explained.The energy bandstructure and total density of TiO₂-B are calculated by the Hartree-Fock-Slater method of density functional theory.2.The prepared TiO₂-B can be composed of lithium ion battery and then test their electric properties.the lithium ion battery showed good stability at constant rate.Under 0.2C,the prepared TiO₂-B still maintains good stability at 10 C after 1000 cycles,and also showed strong persistence.In addition,variable rate test can be seen: the first specific discharge capacity is about 258.7m Ahg-1,and after a variable rate discharge from the 0.1C to the next0.1C,the performance of the battery is not greatly changed,and the battery can be used under variable magnification.3.Based on hydrothermal-coprecipitation method?In content 1?for the synthesis of mesoporous TiO₂,TiO₂ is synthesized through one step hydrothermal method.and this paper explores the formation process of mesoporous TiO₂ through the comparison of two kinds of experimental design,and gets the conclusion: One step hydrothermal method can be used to obtain high crystallinity anatase particles.That is to say,the formation of anatase may be mainly from hydrothermal phase,and the lattice structure of sodium titanate can be the basis of anatase lattice structure.In this paper,this paper introduces the specific process of the conversion from titanium to anatase through the comparison of the two experiments.4.By hydrothermal-coprecipitation method,iron,cobalt,nickel ions are doped into TiO₂ respectively,and their photocatalytic properties are measured by controlling the variables.This paper also finds that,influence of ion valence is the largest for these three kinds of doping ions.Based on the hydrothermal-coprecipitation method,this paper makes three kinds of doping ions extend to the first doping transition metal elements,and establishes photocatalytic model of titanium dioxide doping with the first transition metal elements.