Preparation Of Titanium Nitride/Carbon Composite Materials And Their Electrochemical Performance

With the rapid development of society and economy,the electronic products are becoming indispensable in People's lives.Supercapacitors,one of the most important electrochemical energy storage device,become the hot research topic gradually.The electrode materials are one of the most important factors affecting the electrochemical performance of supercapacitors.Transition metal nitrides?like TiN,VN,etc.?as supercapacitors electrode materials possess many advantages such as good electrical conductivity,high thermal and chemical stability,and so on.When combine transition metal nitrides and carbon,the supercapacitor's electrochemical performance can be further improved.The main purpose of this paper is to synthsis TiN/C composite materials by a simple and environmentally friendly chemical method,then,study the relationship between supercapacitor's electrochemical properties and the composition and structure of the materials.TiN/C composite materials are in-situ synthesized by a dispersion-annealing two-step method.In the dispersion process,the nitrogen and titanium sources are connected to each other by adding a complexing agent,and then the TiN/C composite materials are in-situ produced by annealing the solid precursors,which are obtained by centrifuging the above dispersion liquid,in a nitrogen atmosphere.TiN nanoparticles having a size of about 10 nm are densely and uniformly dispersed on the carbon substrate.The TiN/C composite materials have high specific surface areas and the highest specific surface area reaches 198 m² g^-1.When used as the electrode materials for supercapacitors,the materials exhibit a high specific capacitance of 159F g^-1 at the current density of 0.5 A g^-1 and the specific capacitance can be maintained at 96 F g^-1 at the current density of 20 A g^-1.The simple and environmentally friendly method could be a promising strategy for the low-cost and large-scale synthesis of metal nitride/carbon composite materials.The TiN/C composite materials are in-situ synthesized by a solvothermal-annealing two-step method which further enhances the specific surface area and the electrochemical perfermance of the TiN/C composite materials.First,NH₂-MIL-125?Ti?with a porous structure and ultra-high specific surface area synthesized by solvothermal method is used as the titanium source.And then,the TiN/C composite materials are obtained by annealing the mixtures of Ti-MOF and melamine,in this process,the necessarily reducing atmosphere was provided by the ammonia gas releasing from the pyrolysis process of melamine.Because of the high specific surface area of MOFs,the composite materials are fluffy and porous,and possess a high specific surface area,up to 541 m² g^-1.When used as the supercapacitors'electrode materials,the highest specific capacitance they exhibit is 217 F g^-1 at the current density of 0.5 A g^-1.This work provides a novel strategy to develop high surface area transition metal nitride/carbon composite materials.