The Doping Effect On The Magnetic Properties Of BN And InN Induced By The Modulation Of Electric Structure

Semiconductors with magnetic properties have very broad applications in many fields.Hexagonal boron nitride?h-BN?,which is a structural analog graphite,have more important advantageous properties,such as high thermal conductivity,anti-oxidation ability,chemical inertness,among others.Wurtzite indium nitride has excellent electrical properties,stable chemical and mechanical properties,etc.Therefore,the magnetic properties of hexagonal boron nitride and wurtzite indium nitride were selected as research objects.The main research results are as follows:The stability of h-BN is destroyed due to the oxygen doping in the layer,which resulting in the creation of magnetic and electrical properties.The reaction time is key factor to modulate the Ms values of h-BN nanoparticles.The Ms value reaches a maximum value of 0.2975 emu g^-1 as the reaction time is 12 h.The coupling between B 2p orbital,N 2p orbital and O 2p orbital in the conduction bands is the main origin of magnetic properties.With the decrease of temperature,the current value of hBN film decreases.Presenting semiconductor properties.Due to the oxygen doping,the Fermi level shift to the conduction band and then cross it t,which is responsible for the conductivity of the oxygen-doped h-BN nanoparticles.Unlike oxygen doping,sodium doping is a two-interlayers doping.The coupling between N 2s,2p orbitals and Na 3s orbital lead to the sodium-doped h-BN microbelts exhibiting room temperature ferromagnetism.Different sodium doping concentrations of h-BN microbelts correspond to different saturation magnetizations.The electrical test results of a single sodium doped h-BN microbelt show that with the decrease of temperature the current value decreases.Presenting semiconductor properties.The Na doped led to the shift of the Fermi level in the direction of the conduction band direction and crossing of the conduction band.Thus,the system exhibits a certain level of electrical conductivity.Dy-doped InN nanosheets with different doping concentrations were synthesized.With the increase of doping concentration,the Ms values exhibit a parabolic shape.The maximum value can reach 0.1455 emu/g.The source of magnetic properties of the sample is mainly from the 4f orbital of Dy.The polarization state density indicates that only the electrons with the spin up cross the Fermi surface so the Dy doped system displays an obvious half metallic characteristic.Ce-doped InN nanosheets with different doping concentrations were synthesized.With the increase of doping concentration,the Ms values exhibit a parabolic shape.The maximum value can reach 0.125 emu/g.The source of magnetic properties of the sample is mainly from the 4f orbital of Ce.The polarization state density indicates that the Fermi level passes through the spin-up and spin-down electrons of the valence band,so the Ce doped system exhibiting metallic ferromagnetism.Mn-doped InN nanoparticels with different doping content were synthesized.With the increase of doping concentration,the Ms values exhibit a parabolic shape.The maximum value can reach 0.2998 emu/g.The source of magnetic properties of the sample is mainly from the 3d orbital of Mn.The Fermi level crosses the spin-up electrons of the conduction band due to Mn doping,therefore the Mn doped system exhibits half metallic ferromagnetism.The phenomenon of the Ms values of different ion-doped InN nanomaterials increases first and then decreases with the increase of doping concentration can be explained by the theory of bound magnetic polaron based on the exchange interaction between local carrier and impurity ion exchange.When the doping concentration is higher than a certain value,the antiferromagnetic interaction between adjacent dopant ions weakens the ferromagnetic behavior,resulting in a decrease in the Ms value of the sample.