| In recent years,AIN has been widely studied because of its excellent physical and chemical properties,and AIN nanomaterials have potential applications in nanodevices such as optics,electricity,and magnetism.This paper uses the first principles method to study the evolution of AIN nanoclusters in terms of atomic and electronic structures.The characteristics of the metal atoms adsorbed by the large-scale AIN cluater are studied.A comparative study on the haze gas adsorption between heteroatom modified Al60N60 nanoclusters and pure clusters was carried out.In addition,we discovered a new type of AIN nanowire structure and performed theoretical prediction research.The main research contents and findings of this article are as follows:Small AIN clusters grow preferentially in the longitudinal direction at the early stage of structural evolution.When the longitudinal dimension is stable,large Al60N60 cluster is obtained by transverse growth.As the cluster grows,the absolute value of binding energy gradually increases,the total energy value of the cluster almost increases linearly,and the geometric structure gradually becomes closer.As for the electronic structure of AIN cluster,HSE06 hybrid functional calculations show that with the atomic structure evolves from small to large,the state density curve is more and more continuous,tending to the crystal structure of wurtzite AIN.It has been found in atomic adsorption studies that Al60N60 clusters have similar chemisorption characteristics for N and Cu atoms,both N and Cu atoms are likely to adsorb and accumulate at the edge sites on the top and side of Al60N60 cluster.In terms of electronic structure,the electronic density of state curve of N and Cu atom chemisorption system has similar deep level occupation near Fermi level.When pure Al60N60 cluster adsorb five haze gases,it is found that NO,NO2,CO,CO2 and SO2 were adsorbed on top.b,edge.ap,edge.ah,edge.ap and siedge.ah site of Al60N60 cluster,respectively,the structure of the adsorption system is relatively stable,the adsorption energy value is relatively high,and the charge transfer is relatively large.In these types of adsorption systems,there is strong chemical adsorption between Al60N60 clusters and gas.Pure Al60N60 cluster before and after adsorption NO2 gas,the energy gaps have changed by 44%.It was found that Al60N60 clusters were modified by Ti,Si and Mn atoms,the corresponding structures of Ti,Si and Mn atoms adsorbed on the top sites of Al60N60 clusters were relatively stable,with high adsorption energy values and uniform charge distribution.The characteristics of haze gas adsorption by these heterogeneous atoms modified clusters were studied,these three atom-modified Al60N60 nano-cluster materials are not sensitive to CO2 gas and are not suitable for its gas-sensitive materials.Ti atom-modified Al60N60 cluster adsorbs CO and SO2 gas,and the energy gap decreases sharply.Compared with the pure clusters adsorption system,the energy gaps have changed by 62%and 50%.The new AIN nanowire structure is propeller-shaped and consists of three"blades".The structure has three longitudinal and three inclined Al-N bond lengths.The hybridization methods of Al and N atoms are related to the spatial configuration and coordination number.The corresponding hybridization methods of atoms with coordination numbers 3,4,and 5 are sp2,sp3,and sp3d,respectively.The binding energy and work function of the new AIN nanowire structure are-4.86eV and-5.33eV,respectively.According to the Bader charge analysis,the charge change of the Al and N atoms at the connection of the three leaves is the largest.From the blade connection in sequence outward,the electron loss of the Al atom gradually decreases,and the electrons obtained by the N atom gradually decrease.It is found that the magnetic distance of the structure is zero and the energy gap is 2.5eV.This new AIN nanowire structure is a kind of non-magnetic semiconductor material. |
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