Combustion Synthesis Of Carbon Nanomaterials And Its Energy Storage Applications

Flame method is one of the effective methods to prepare carbon nanomaterials(including soot and carbon nanotubes).Although it is not the mainstream method,it has unique advantages;for example,the preparation process is carried out in the atmosphere without vacuum(Arc method)and protective atmosphere(CVD method);a uniform carbon nanomaterial film can be prepared on a large surface;the cost is low,and the environmental pollution is small.In this paper,the growth mechanism,physical and chemical properties and application of carbon nanomaterials in flames are explored and revealed.The main pioneering and innovative achievements are as follows:(1)The effects of methane and ethylene on soot formation in different oxygen concentrations and the mixture of methane and ethylene were studied by means of thermophoresis probe sampling followed by transmission electron microscope analysis.The nucleation,surface growth,agglomeration and oxidation of soot particles along the axis were analyzed.The particle size distribution and aggregation characteristics of soot with different oxygen concentration and methane doping rate were obtained.(2)One-dimensional carbon nanomaterials(carbon nanotubes and carbon nanofibers)were prepared by flame method.Carbon nanomaterials were prepared by combustion of gaseous fuel(mainly including methane,ethylene,etc.);the growth mechanism of one-dimensional carbon nanomaterials in flame were revealed;the effects of fuel structure and sampling substrate on the synthesis of carbon nanotubes were discussed,and the recursive growth mode was proposed for the first time.(3)The application of one-dimensional carbon nanomaterials prepared by flame method was explored.One is the flame synthesis of carbon nanotubes as the negative electrode of sodium ion batteries.The two is the growth of carbon nanotubes directly on foam nickel,which is directly used as negative electrode of sodium ion batteries,which significantly improves the capacitance and has the best electrochemical performance.Flame synthesized carbon nanomaterials have rich defects and highly disordered structure,and are ideal materials for preparing high performance sodium ion batteries.At the same time,the flame synthesis of carbon nanomaterials can be further extended to other related energy storage systems and electrocatalytic systems.