Black Arsenic-phosphorus(AsP)monolayer is a novel two-dimensional nanomaterial with the characteristics of modest direct bandgap and superhigh carrier mobility.However,little is known about how the surface adsorption ...Black Arsenic-phosphorus(AsP)monolayer is a novel two-dimensional nanomaterial with the characteristics of modest direct bandgap and superhigh carrier mobility.However,little is known about how the surface adsorption affects the property of AsP monolayer.Motivated by this,we researched systematically the geometry,adsorption energy,magnetic moment and electronic structure of 11 different adatoms adsorbed on AsP monolayer using firstprinciples calculations.The adatoms used in this study include light nonmetallic(C,N,O)adatoms,period-3 metal(Na,Mg,Al)adatoms,and transition-metal(Ti,V,Cr,Mn,and Fe)adatoms.The adatoms cause an abundant variety of structural,magnetic and electronic properties.This study shows that AsP binds strongly with all adatoms under study and the adsorption energies in all systems are much stronger than that on graphene,Si C,BN,or MoS2.The semiconductor property of AsP is affected by the introduction of adsorbed atoms,which can induce mid-gap states or cause n-type doping.Moreover,the adatom adsorptions cause various spintronic characteristics:N-,Ti-,and Fe-adsorbed AsP become bipolar semiconductors,while the Mn-decorated AsP becomes a bipolar spin-gapless semiconductor.Our results suggest that atomic adsorption on AsP monolayers has potential application in the field of nanoelectronics and spintronics.展开更多
Advanced electromagnetic(EM)wave absorbing materials with strong absorption and broad bandwidth are important for military stealth and elimination of microwave pollution in consumers’electronics.Metal organic framewo...Advanced electromagnetic(EM)wave absorbing materials with strong absorption and broad bandwidth are important for military stealth and elimination of microwave pollution in consumers’electronics.Metal organic framework(MOF)-derived metal/carbon hybrids with ordered structure are significantly urgent in this field.In this contribution,we presented a design strategy of hollow cage-like or solid box-like magnetic/dielectric Fe/Co/C and dielectric Fe/Mn/C EM wave absorbing nanomaterials via pyrolyzing Prussian blue’s analogs with controllable topology and phase composition.The solid box-like Fe/Co/C and hollow cage-like Fe/Mn/C showed favorable absorption property with a broad effective absorption bandwidth(EAB)and a low reflection loss(RL).Especially,the EAB of 8.8 GHz at a thickness of 2.5 mm for solid box-like Fe/Co/C nanocomplex prepared at 900℃is a new record for this type of materials.The design and tuning strategy for EM wave absorbers derived from topology-controllable MOF is important for EM functional materials possessing great potential in military stealth and consumers’electronics.展开更多
Ni1-xZnxFe2O4(0≤x≤1,in steps of 0.1) nanocrystallines were synthesized by sol-gel route.The doping effects of zinc on structural,magnetic and microwave absorption properties were investigated in detail.X-ray diffrac...Ni1-xZnxFe2O4(0≤x≤1,in steps of 0.1) nanocrystallines were synthesized by sol-gel route.The doping effects of zinc on structural,magnetic and microwave absorption properties were investigated in detail.X-ray diffraction(XRD) results show that all the samples are single-phase spinel structure.The magnetic and microwave absorption properties are strongly dependent on the zinc content,which can be understood in terms of the cations redistribution in spinel tetrahedral and octahedral sites with the increase of zinc content.The magnetic measurement shows the antiferromagnetic nature of the samples for x=0.9 and x=1.0.The saturation magnetization reaches the maximum of 3.35μB/f.u.at x=0.5.The optimal reflection loss(RL) of-29.6 dB is found at 6.5 GHz for an absorber thickness of 5 mm.The RL values exceeding 10 dB are obtained for the absorber in the range of 3.9-8.9 GHz.These Ni1-xZnxFe2O4 nanocrystallines may be attractive candidates for electromagnetic wave absorption materials.展开更多
The neutrino-dominated disk is regarded as a plausible model for the central engine of Gamma-Ray Bursts. By taking into account magnetic fields and detailed microphysics, we calculate the structure of neutrino-dominat...The neutrino-dominated disk is regarded as a plausible model for the central engine of Gamma-Ray Bursts. By taking into account magnetic fields and detailed microphysics, we calculate the structure of neutrino-dominated disks in the frame of the well-known Paczy nski-Witta potential. The results show that the temperature of the disk is lower than that without magnetic fields, whereas the density is nearly the same as that without magnetic fields. There also exists a significant difference in the electron degeneracy between the above two cases. In addition, we present the variation of the electron fraction with the radius.展开更多
基金supported by the National Natural Science Foundation of China(No.11404268 and No.11774294)the Sichuan Province Applied Science and Technology Project(No.2017JY0056)the R&D Program for International ST Cooperation and Exchanges of Sichuan province(No.2018HH0088)。
文摘Black Arsenic-phosphorus(AsP)monolayer is a novel two-dimensional nanomaterial with the characteristics of modest direct bandgap and superhigh carrier mobility.However,little is known about how the surface adsorption affects the property of AsP monolayer.Motivated by this,we researched systematically the geometry,adsorption energy,magnetic moment and electronic structure of 11 different adatoms adsorbed on AsP monolayer using firstprinciples calculations.The adatoms used in this study include light nonmetallic(C,N,O)adatoms,period-3 metal(Na,Mg,Al)adatoms,and transition-metal(Ti,V,Cr,Mn,and Fe)adatoms.The adatoms cause an abundant variety of structural,magnetic and electronic properties.This study shows that AsP binds strongly with all adatoms under study and the adsorption energies in all systems are much stronger than that on graphene,Si C,BN,or MoS2.The semiconductor property of AsP is affected by the introduction of adsorbed atoms,which can induce mid-gap states or cause n-type doping.Moreover,the adatom adsorptions cause various spintronic characteristics:N-,Ti-,and Fe-adsorbed AsP become bipolar semiconductors,while the Mn-decorated AsP becomes a bipolar spin-gapless semiconductor.Our results suggest that atomic adsorption on AsP monolayers has potential application in the field of nanoelectronics and spintronics.
基金This work was financially supported by the National Natural Science Foundation of China(21875190)Polymer Electromagnetic Functional Materials Innovation Team of Shaanxi Sanqin Scholars,the Natural Science Basic Research Plan in Shaanxi Province of Distinguished Young Scholar(2018JC-008)China Postdoctoral Science Foundation(2018M643724).
文摘Advanced electromagnetic(EM)wave absorbing materials with strong absorption and broad bandwidth are important for military stealth and elimination of microwave pollution in consumers’electronics.Metal organic framework(MOF)-derived metal/carbon hybrids with ordered structure are significantly urgent in this field.In this contribution,we presented a design strategy of hollow cage-like or solid box-like magnetic/dielectric Fe/Co/C and dielectric Fe/Mn/C EM wave absorbing nanomaterials via pyrolyzing Prussian blue’s analogs with controllable topology and phase composition.The solid box-like Fe/Co/C and hollow cage-like Fe/Mn/C showed favorable absorption property with a broad effective absorption bandwidth(EAB)and a low reflection loss(RL).Especially,the EAB of 8.8 GHz at a thickness of 2.5 mm for solid box-like Fe/Co/C nanocomplex prepared at 900℃is a new record for this type of materials.The design and tuning strategy for EM wave absorbers derived from topology-controllable MOF is important for EM functional materials possessing great potential in military stealth and consumers’electronics.
基金supported by the National Natural Science Foundation of China (Grant Nos.10874051,51002156,and 11104098)the Natural Science Major Foundation of Anhui Provincial Higher Education Institutions of China (Grant No. KJ2012ZD14)
文摘Ni1-xZnxFe2O4(0≤x≤1,in steps of 0.1) nanocrystallines were synthesized by sol-gel route.The doping effects of zinc on structural,magnetic and microwave absorption properties were investigated in detail.X-ray diffraction(XRD) results show that all the samples are single-phase spinel structure.The magnetic and microwave absorption properties are strongly dependent on the zinc content,which can be understood in terms of the cations redistribution in spinel tetrahedral and octahedral sites with the increase of zinc content.The magnetic measurement shows the antiferromagnetic nature of the samples for x=0.9 and x=1.0.The saturation magnetization reaches the maximum of 3.35μB/f.u.at x=0.5.The optimal reflection loss(RL) of-29.6 dB is found at 6.5 GHz for an absorber thickness of 5 mm.The RL values exceeding 10 dB are obtained for the absorber in the range of 3.9-8.9 GHz.These Ni1-xZnxFe2O4 nanocrystallines may be attractive candidates for electromagnetic wave absorption materials.
基金supported by the Innovation Program for Young Scientists of Fujian Province of China (Grant No. 2007F3105)
文摘The neutrino-dominated disk is regarded as a plausible model for the central engine of Gamma-Ray Bursts. By taking into account magnetic fields and detailed microphysics, we calculate the structure of neutrino-dominated disks in the frame of the well-known Paczy nski-Witta potential. The results show that the temperature of the disk is lower than that without magnetic fields, whereas the density is nearly the same as that without magnetic fields. There also exists a significant difference in the electron degeneracy between the above two cases. In addition, we present the variation of the electron fraction with the radius.
