Study On Spray Self-propagating ITO Nano-powder Synthesis Based On Single Droplet Reaction Characteristics

With the development of computer science and technology,the demand for communication and electronic equipment is increasing rapidly.Indium tin oxide,widely used in electronic devices such as mobile phone screens,has the characteristics of low resistivity and high visible light transmittance.Under the leadership of the principal teacher Zhu yuan,the research team of the author developed the technology of preparing nano powder by spray self-propagating method.Taking indium tin oxide material system as an example,this paper explores the preparation technical route and optimal formula to prepare particles with good geometric morphology,uniform particle size distribution and excellent lattice quality.In this paper,urea and glucose were selected as the combustion agent,and ammonium nitrate as the combustion agent.Experiments were carried out based on theoretical calculation and ratio,and various characterization methods were used to explore the synthesis of different combustion agents.Considering the shortage of single combustion agent,composite combustion agent was used in the experiment,and the control experiment was designed to explore the influence of composite combustion agent dose,proportion of combustion agent and proportion of combustion agent on the synthetic powder.Finally,the optimal formula was obtained.The indium tin oxide nano-powder prepared by self-propagating spray with an optimized formula is cubic crystal with a minimum particle size of about 10 nm and a uniform particle size distribution.It is a pure phase alloy with good powder quality.Further,in order to solve the problem of insufficient synthetic reaction in spray self-propagating and explore the reaction characteristics of self-exothermic droplets,the micro-self-spreading synthesis was studied by using the micro-droplet system,and the influence of the experimental characteristics and parameters of single droplet reaction was explored.In this project,a single droplet experiment system is set up,a mass measurement method of tiny droplet based on lever principle is developed,and the temperature and mass of droplet during combustion process are measured synchronously with the infrared thermal imager.The experimental results of combustion characteristics show that after the droplet is ignited at about 180?,the temperature increases sharply and the mass decreases rapidly.After that,the droplet completes the expansion combustion in a very short time,and the maximum combustion temperature can reach 650?.Combined with the temperature mass change curve and reaction enthalpy change,the change course of the three-stage exothermic reaction of droplet self-propagation was reflected,and the importance of the ratio of reactant of precursor was confirmed.For the droplet evaporation section,the droplet diameter change was calculated and the droplet evaporation constant was obtained by fitting.Furthermore,the influence of initial concentration,volume and temperature of single droplet on the experimental characteristics of combustion was investigated.At last,the research of droplet reaction mechanism is prospected and some suggestions are put forward.