The nickel‐based complex Ni‐CH3CH2NH2‐intercalated niobate layered perovskite Ni‐CH3CH2NH2/H1.78Sr0.78Bi0.22Nb2O7was synthesized via a facile in situ chemical reaction method.Using ultrathin H1.78Sr0.78Bi0.22Nb2O7...The nickel‐based complex Ni‐CH3CH2NH2‐intercalated niobate layered perovskite Ni‐CH3CH2NH2/H1.78Sr0.78Bi0.22Nb2O7was synthesized via a facile in situ chemical reaction method.Using ultrathin H1.78Sr0.78Bi0.22Nb2O7nanosheets and nickel acetate as precursors.The composition,structure,photophysical properties,and photocatalytic activity for H2production of Ni‐CH3CH2NH2/H1.78Sr0.78Bi0.22Nb2O7were studied systematically.The photocatalyst loaded with0.5wt%Ni exhibited the highest H2evolution rate of372.67μmo/h.This was0.54times higher than the activity of the H1.78Sr0.78Bi0.22Nb2O7nanosheets.The activity of the optimized Ni‐CH3CH2NH2/H1.78Sr0.78Bi0.22Nb2O7was comparable to that of the Pt‐loaded sample under the same reaction conditions.The photocatalytic activity of the Ni‐CH3CH2NH2/H1.78Sr0.78Bi0.22Nb2O7was mainly attributed to the excellent separation of photogenerated carriers,after formation of the intercalated complex Ni‐CH3CH2NH2.This study provides a facile strategy to synthesize a non‐precious metal‐loaded photocatalyst for H2production.展开更多
The thermodynamic properties of the bilayer ruthenate compound Sr3Ru2O7 at very low temperatures are inves- tigated by using a tight-binding model yielding the realistic band structure combined with the on-site intera...The thermodynamic properties of the bilayer ruthenate compound Sr3Ru2O7 at very low temperatures are inves- tigated by using a tight-binding model yielding the realistic band structure combined with the on-site interactions treated at the mean-field level. We find that both the total density of states at the Fermi energy and the entropy exhibit a sudden increase near the critical magnetic field for the nematic phase, echoing the experimental find- ings. A new mechanism to explain the anisotropic transport properties is proposed based on scatterings at the anisotropic domain boundaries. Our results suggest that extra cares are necessary to isolate the contributions due to the quantum criticality from the band structure singularity in Sr3Ru2O7.展开更多
New phosphors Sr2ZnSi2O7: M (M=Mn2+, Tb3+) were synthesized through solid-state reaction, and their photoluminescent properties under UV and VUV region were investigated. The results showed that Sr2ZnSi2O7:Mn2+...New phosphors Sr2ZnSi2O7: M (M=Mn2+, Tb3+) were synthesized through solid-state reaction, and their photoluminescent properties under UV and VUV region were investigated. The results showed that Sr2ZnSi2O7:Mn2+ emitted green light with the strongest emission peak centered at 525 nm, and its quenching concentration under 254 and 147 nm excitation occurred at x = 0.08 and 0.06, respectively. Sr2ZnSi2O7: Th3+ emitted green light with the strongest emission peak centered at 541 nm, and its quenching concentration under 254 and 147 nm excitation also appeared at y = 0.25. At 147 nm excitation, the emission intensities of Sr2Zn0.54Si2O7: 0.06Mn2+ and Sr1.75ZnSi2O7: 0.25Tb3+ phosphors were 54% and 36% of that of Zn1.96SiO4:0.04Mn2+, respectively. And their decay times (τ1/e) were about 3.18 ms and 3.9 ms, respectively.展开更多
采用溶胶-凝胶法将TiO2-x N x包覆在长余辉光致发光材料(Sr2MgSi2O7∶Eu2+,Dy3+)表面制备得到TiO2-x N x/Sr2MgSi2O7∶Eu2+,Dy3+复合材料。利用X-射线衍射(XRD)、扫描电子显微镜(SEM)对TiO2-x N x/Sr2MgSi2O7∶Eu2+,Dy3+复合光催化材料...采用溶胶-凝胶法将TiO2-x N x包覆在长余辉光致发光材料(Sr2MgSi2O7∶Eu2+,Dy3+)表面制备得到TiO2-x N x/Sr2MgSi2O7∶Eu2+,Dy3+复合材料。利用X-射线衍射(XRD)、扫描电子显微镜(SEM)对TiO2-x N x/Sr2MgSi2O7∶Eu2+,Dy3+复合光催化材料的结构及表面形貌进行表征,并研究了TiO2-x N x/Sr2MgSi2O7∶Eu2+,Dy3+复合光催化材料对甲基橙溶液的降解性能。展开更多
Nanosized Gd2(1–x)Eu2xTi2O7:yV5+ phosphors were prepared via sol-gel method and characterized with X-ray diffraction,Raman spectroscopy,diffuse reflectance spectra and photoluminescence spectra.Their PL properties we...Nanosized Gd2(1–x)Eu2xTi2O7:yV5+ phosphors were prepared via sol-gel method and characterized with X-ray diffraction,Raman spectroscopy,diffuse reflectance spectra and photoluminescence spectra.Their PL properties were investigated as functions of the Eu3+ doping concentration and annealing temperature.The results indicated that the as-prepared samples showed a strong emission of Eu3+ under the irradiation of 303 nm.For Eu3+-doped Gd2Ti2O7,the orange emission at 586 nm was the strongest,which was correspond...展开更多
基金supported by the National Natural Science Foundation of China(U1403193,21643012)~~
文摘The nickel‐based complex Ni‐CH3CH2NH2‐intercalated niobate layered perovskite Ni‐CH3CH2NH2/H1.78Sr0.78Bi0.22Nb2O7was synthesized via a facile in situ chemical reaction method.Using ultrathin H1.78Sr0.78Bi0.22Nb2O7nanosheets and nickel acetate as precursors.The composition,structure,photophysical properties,and photocatalytic activity for H2production of Ni‐CH3CH2NH2/H1.78Sr0.78Bi0.22Nb2O7were studied systematically.The photocatalyst loaded with0.5wt%Ni exhibited the highest H2evolution rate of372.67μmo/h.This was0.54times higher than the activity of the H1.78Sr0.78Bi0.22Nb2O7nanosheets.The activity of the optimized Ni‐CH3CH2NH2/H1.78Sr0.78Bi0.22Nb2O7was comparable to that of the Pt‐loaded sample under the same reaction conditions.The photocatalytic activity of the Ni‐CH3CH2NH2/H1.78Sr0.78Bi0.22Nb2O7was mainly attributed to the excellent separation of photogenerated carriers,after formation of the intercalated complex Ni‐CH3CH2NH2.This study provides a facile strategy to synthesize a non‐precious metal‐loaded photocatalyst for H2production.
基金Supported by the NSF DMR-1410375 and AFOSR FA9550-14-1-0168the President's Research Catalyst Award(No CA-15-327861) from the University of California Office of the Presidentthe CAS/SAFEA International Partnership Program for Creative Research Teams
文摘The thermodynamic properties of the bilayer ruthenate compound Sr3Ru2O7 at very low temperatures are inves- tigated by using a tight-binding model yielding the realistic band structure combined with the on-site interactions treated at the mean-field level. We find that both the total density of states at the Fermi energy and the entropy exhibit a sudden increase near the critical magnetic field for the nematic phase, echoing the experimental find- ings. A new mechanism to explain the anisotropic transport properties is proposed based on scatterings at the anisotropic domain boundaries. Our results suggest that extra cares are necessary to isolate the contributions due to the quantum criticality from the band structure singularity in Sr3Ru2O7.
基金Funded by Key Project of Natural Science for Education Department of Sichuan Province(No.14ZA0102)State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials,Southwest University of Science and Technology,Mianyang
文摘New phosphors Sr2ZnSi2O7: M (M=Mn2+, Tb3+) were synthesized through solid-state reaction, and their photoluminescent properties under UV and VUV region were investigated. The results showed that Sr2ZnSi2O7:Mn2+ emitted green light with the strongest emission peak centered at 525 nm, and its quenching concentration under 254 and 147 nm excitation occurred at x = 0.08 and 0.06, respectively. Sr2ZnSi2O7: Th3+ emitted green light with the strongest emission peak centered at 541 nm, and its quenching concentration under 254 and 147 nm excitation also appeared at y = 0.25. At 147 nm excitation, the emission intensities of Sr2Zn0.54Si2O7: 0.06Mn2+ and Sr1.75ZnSi2O7: 0.25Tb3+ phosphors were 54% and 36% of that of Zn1.96SiO4:0.04Mn2+, respectively. And their decay times (τ1/e) were about 3.18 ms and 3.9 ms, respectively.
文摘采用溶胶-凝胶法将TiO2-x N x包覆在长余辉光致发光材料(Sr2MgSi2O7∶Eu2+,Dy3+)表面制备得到TiO2-x N x/Sr2MgSi2O7∶Eu2+,Dy3+复合材料。利用X-射线衍射(XRD)、扫描电子显微镜(SEM)对TiO2-x N x/Sr2MgSi2O7∶Eu2+,Dy3+复合光催化材料的结构及表面形貌进行表征,并研究了TiO2-x N x/Sr2MgSi2O7∶Eu2+,Dy3+复合光催化材料对甲基橙溶液的降解性能。
基金supported by Cultivating Innovative Talents for Colleges & Universities of Henan Province (2002006)Open Research Foundation of Henan University
文摘Nanosized Gd2(1–x)Eu2xTi2O7:yV5+ phosphors were prepared via sol-gel method and characterized with X-ray diffraction,Raman spectroscopy,diffuse reflectance spectra and photoluminescence spectra.Their PL properties were investigated as functions of the Eu3+ doping concentration and annealing temperature.The results indicated that the as-prepared samples showed a strong emission of Eu3+ under the irradiation of 303 nm.For Eu3+-doped Gd2Ti2O7,the orange emission at 586 nm was the strongest,which was correspond...