Study On Preparation And Physical Properties Of Solution Derived Ternary Metal Nitride ANM₃?M=Cu,Ni,Co?Films

Transition metal nitrides with high hardness,high thermal conductivity,high melting point,high chemical stability,superior catalytic activity and other properties can be widely used in many fields.Many studies have focused on binary metal nitrides,such as MoN,TiN,and NbN.However,since the 1980s,ternary metal nitride has become a hot topic in the field of new materials due to its rich physical properties and potential functional properties.ANM3(A=Al,Ag,Pd,In,Ga,Zn,Ge,etc.M=Fe,Co,Ni,Cu,Mn,Cr,etc.)compound with antiperovskite structure is one of the main research systems of ternary metal nitride.In order to better study the growth mechanism and physical properties of metal nitrides with antiperovskite structure,the preparation of single crystal and high quality film has become an effective method.However,as the melting point of metal nitride is very high,the phase diagram is complex,the introduction of N element is difficult and it is easy to oxidize during the high-temperature synthesis,it is difficult to obtain single crystal and high quality film of antiperovskite nitride,which limits the study of its physical properties.In this dissertation,the ternary metal antiperovskite nitride ANM3 is selected as the research object.Several kinds of anti-perovskite nitrides are prepared by chemical solution method,the microstructure,electrical transport,optical properties and magnetic properties of the derived thin films are systematically investigated.The main research contents are included as follows:1.The Cu3NPdx(x=0,0.05,0.1,0.2)thin films were prepared and the optoelectronic properties were investigated.The results showed that Cu3NPdx films were prepared successfully on glass substrate by chemical solution deposition and Pd atoms occupy the body center position.In addition,the prepared thin films show semiconductor electronic transport properties.With the increasing of palladium doping,the electrical conductivity increases significantly.Pd doping can effectively adjust the optical band gap of Cu3NPdx thin film:The transmittance and optical band gap significantly decreased with the increasing of Pd doping.2.The preparation and the electronic transport properties of ANNi3(A=Cu,Pd,Pt)thin films were systematically investigated.The results showed that pure phase PdNNi3,PtNNi3 and CuNNi3 films were prepared by chemical solution deposition.This work mainly provides an effective process for the preparation of ANNi3 film.The superconducting transition temperature of the CuNNi3 film is 3.16 K,while PdNNi3 and PtNNi3 are shown as metallic electronic transport properties in the temperature range of 2-350 K.There was no superconductivity in the entire temperature range,which is consistent with the theoretical prediction.3.The preparation and magnetic properties of FeNNi3 thin film were investigated.FeNNi3 polycrystalline films were prepared on Si substrate for the first time by chemical solution deposition.By selecting the proper substrate with the similar lattice constant,c-axis orientation is observed for all the prepared thin films on SrTiO3 substrate that annealed in the temperature range of 500-650?.The result of ?-scans show that the epitaxial FeNNi3 thin film on SrTiO3 substrate is obtained by annealing at 600?.From the magnetic measurements,it is concluded that FeNNi3 can be classified into a low temperature soft-magnetic material with Curie temperature of 265 K.As the annealing temperature increases,the saturated magnetization increases,which is due to the improvement of crystalline quality and a slight increase of nitrogen content.4.The preparation,the magnetic and electronic transport properties of PdNCo3 epitaxial thin film were systematically studied.The results showed that the PdNCo3 film was synthesized for the first time.The epitaxial PdNCo3 film with antiperovskite structure was successfully prepared on the SrTiO3 substrate.The derived thin films show metallic electronic transport properties and at high temperatures(70-350 K)the resistivity is dominated by the electron-phonon scattering,while at low temperatures(5-70 K)the electron-electron interaction plays a very important role,which suggests the Fermi liquid behavior.From the magnetic measurements,it is concluded that PdNCo3 can be classified into a new type of soft-magnetic material with Curie temperature higher than 619 K.The saturated magnetization and coercive field are 80 emu/cm3 and 125 Oe respectively.