The crystal structures and magnetic properties of novel Eu TrGa3-r (T=Pd, It, Rh) in termetallic compounds are investigated by using powder x-ray diffraction and magnetic measurements. EuTrGa3-r crystallizes in orth...The crystal structures and magnetic properties of novel Eu TrGa3-r (T=Pd, It, Rh) in termetallic compounds are investigated by using powder x-ray diffraction and magnetic measurements. EuTrGa3-r crystallizes in orthorhombic structure with space group of Cmcm and Z = 4. There are four kinds of nonequivalent 4c crystal positions in EuTrGaa-r unit cell, which are occupied by 4Eu, 4GaⅠ, 4(GaⅡ, T) and 4GaⅢ, respectively. EuTrGa3-r ex- hibits the complex magnetic states in low-temperature regime, with the three-, two- and one-antiferromagnetic transitions occurring for T=Ir, T=Rh and T=Pd, respectively. It might be due to the Kondo effect: a localized antiferromagnetic interaction of the isolated impurity spins with the surrounding conduction electrons at low-temperature regime.展开更多
This study presents the synthesis of a ternary CeO_(2)-AuNR-Cu_(2)O Janus structure with dual Schottky junctions,achieved by sequential growth of CeO_(2) and Cu_(2)O crystal domains on AuNR seeds.The dual Schottky jun...This study presents the synthesis of a ternary CeO_(2)-AuNR-Cu_(2)O Janus structure with dual Schottky junctions,achieved by sequential growth of CeO_(2) and Cu_(2)O crystal domains on AuNR seeds.The dual Schottky junctions and the Janus-type CeO_(2)-Cu_(2)O P-N heterostructure led to significant enhancement in charge separation and suppress of the electron-hole recombination.The localized surface plasmon resonance(LSPR)effect of AuNR and the Z-scheme electron transfer pathway further boost the photocatalytic performance.This enhancement was demonstrated through the model photocatalytic degradation of methylene blue(MB)in aqueous solution.The proposed strategy not only improves photocatalytic efficiency but also provides insights into electron migration mechanisms,offering new opportunities for advanced nanostructure development in various applications.展开更多
A nano-laminated Y_(3)Si_(2)C_(2) ceramic material was successfully synthesized via an in situ reaction between YH_(2)and SiC using spark plasma sintering technology.A MAX phase-like ternary layered structure of Y_(3)...A nano-laminated Y_(3)Si_(2)C_(2) ceramic material was successfully synthesized via an in situ reaction between YH_(2)and SiC using spark plasma sintering technology.A MAX phase-like ternary layered structure of Y_(3)Si_(2)C_(2) was observed at the atomic-scale by high resolution transmission electron microscopy.The lattice parameters calculated from both X-ray diffraction and selected area electron diffraction patterns are in good agreement with the reported theoretical results.The nano-laminated fracture of kink boundaries,delamination,and slipping were observed at the tip of the Vickers indents.The elastic modulus and Vickers hardness of Y_(3)Si_(2)C_(2) ceramics(with 5.5 wt%Y_(2)O_(3)) sintered at 1500℃were 156 and 6.4 GPa,respectively.The corresponding values of thermal and electrical conductivity were 13.7 W·m^(-1)·K^(-1) and 6.3×10^(5)S·m^(-1),respectively.展开更多
Fe_(2)AlB_(2) powder material was prepared by the direct reaction of iron,aluminum and boron powders in a tubular furnace.The effects of different Al contents,temperature and raw material pretreatment on the purity of...Fe_(2)AlB_(2) powder material was prepared by the direct reaction of iron,aluminum and boron powders in a tubular furnace.The effects of different Al contents,temperature and raw material pretreatment on the purity of product were studied.The mixed powder with the stoichiometric ratio of 1.5Al/2Fe/2B was processed by CIP (Cold Isostatic Pressing),and then calcined at 1150℃ for 120 min.The product containing a small amount of impurities is treated with alkaline solution to obtain high-purity Fe_(2)Al B_(2) powder.Zr B_(2)-Fe_(2)Al B_(2) composite ceramic was successfully prepared at 1250℃ by hot pressing sintering.The density,hardness and fracture toughness were 96.2%,22±0.3 GPa and 5.78±0.5 MPa·m^(1/2),respectively.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 11274110
文摘The crystal structures and magnetic properties of novel Eu TrGa3-r (T=Pd, It, Rh) in termetallic compounds are investigated by using powder x-ray diffraction and magnetic measurements. EuTrGa3-r crystallizes in orthorhombic structure with space group of Cmcm and Z = 4. There are four kinds of nonequivalent 4c crystal positions in EuTrGaa-r unit cell, which are occupied by 4Eu, 4GaⅠ, 4(GaⅡ, T) and 4GaⅢ, respectively. EuTrGa3-r ex- hibits the complex magnetic states in low-temperature regime, with the three-, two- and one-antiferromagnetic transitions occurring for T=Ir, T=Rh and T=Pd, respectively. It might be due to the Kondo effect: a localized antiferromagnetic interaction of the isolated impurity spins with the surrounding conduction electrons at low-temperature regime.
基金financially supported by Jiangsu Science and Technology Plan(BK20211258)Nanjing Tech University(39837140)+1 种基金Jiangsu Second Normal University(928201/084)Jiangsu Funding Program for Excellent Postdoctoral Talent(2022ZB372)。
文摘This study presents the synthesis of a ternary CeO_(2)-AuNR-Cu_(2)O Janus structure with dual Schottky junctions,achieved by sequential growth of CeO_(2) and Cu_(2)O crystal domains on AuNR seeds.The dual Schottky junctions and the Janus-type CeO_(2)-Cu_(2)O P-N heterostructure led to significant enhancement in charge separation and suppress of the electron-hole recombination.The localized surface plasmon resonance(LSPR)effect of AuNR and the Z-scheme electron transfer pathway further boost the photocatalytic performance.This enhancement was demonstrated through the model photocatalytic degradation of methylene blue(MB)in aqueous solution.The proposed strategy not only improves photocatalytic efficiency but also provides insights into electron migration mechanisms,offering new opportunities for advanced nanostructure development in various applications.
基金the support from the Ningbo 3315 Innovative Teams Program,China(Grant No.2019A-14-C)This study was supported by the National Natural Science Foundation of China(Grant Nos.11975296 and 51811540402).
文摘A nano-laminated Y_(3)Si_(2)C_(2) ceramic material was successfully synthesized via an in situ reaction between YH_(2)and SiC using spark plasma sintering technology.A MAX phase-like ternary layered structure of Y_(3)Si_(2)C_(2) was observed at the atomic-scale by high resolution transmission electron microscopy.The lattice parameters calculated from both X-ray diffraction and selected area electron diffraction patterns are in good agreement with the reported theoretical results.The nano-laminated fracture of kink boundaries,delamination,and slipping were observed at the tip of the Vickers indents.The elastic modulus and Vickers hardness of Y_(3)Si_(2)C_(2) ceramics(with 5.5 wt%Y_(2)O_(3)) sintered at 1500℃were 156 and 6.4 GPa,respectively.The corresponding values of thermal and electrical conductivity were 13.7 W·m^(-1)·K^(-1) and 6.3×10^(5)S·m^(-1),respectively.
基金supported by the grants of CAS Priority Research Program(XDB20010300,XDA21010204)Science and Technology Program of Fujian Province(2017T3001)。
文摘Fe_(2)AlB_(2) powder material was prepared by the direct reaction of iron,aluminum and boron powders in a tubular furnace.The effects of different Al contents,temperature and raw material pretreatment on the purity of product were studied.The mixed powder with the stoichiometric ratio of 1.5Al/2Fe/2B was processed by CIP (Cold Isostatic Pressing),and then calcined at 1150℃ for 120 min.The product containing a small amount of impurities is treated with alkaline solution to obtain high-purity Fe_(2)Al B_(2) powder.Zr B_(2)-Fe_(2)Al B_(2) composite ceramic was successfully prepared at 1250℃ by hot pressing sintering.The density,hardness and fracture toughness were 96.2%,22±0.3 GPa and 5.78±0.5 MPa·m^(1/2),respectively.