采用静电纺丝法制得La2Co Fe O6竹节状中空纳米纤维光催化材料。La2Co Fe O6纳米纤维具有稳定的一维结构,由菱形晶型的La2Co Fe O6纳米颗粒相互连接组成,并存在明显的竹节状中空结构,其比表面积可达98.7 m2/g。La2Co Fe O6纳米纤维对自...采用静电纺丝法制得La2Co Fe O6竹节状中空纳米纤维光催化材料。La2Co Fe O6纳米纤维具有稳定的一维结构,由菱形晶型的La2Co Fe O6纳米颗粒相互连接组成,并存在明显的竹节状中空结构,其比表面积可达98.7 m2/g。La2Co Fe O6纳米纤维对自然光具有较高的利用率,其禁带宽度为1.6 e V。在甲基橙溶液浓度为10 mg/L,p H为2,催化剂用量为1.5 g/L条件下,自然光光照2 h后,La2Co Fe O6纳米纤维对甲基橙的降解率可达96.9%。展开更多
Nanosized La2-xKxNiMnO6 catalysts with ABO3 type perovskite-like structure were prepared by auto-combustion method using citric acid as a ligand to control particle size and morphology.The structures and properties of...Nanosized La2-xKxNiMnO6 catalysts with ABO3 type perovskite-like structure were prepared by auto-combustion method using citric acid as a ligand to control particle size and morphology.The structures and properties of these perovskite-like oxides were investigated by X-ray powder diffraction(XRD)and temperature-programmed reduction(TPR).The catalytic activities for soot combustion were evaluated by temperature- programmed oxidation(TPO)with pure O2 and O2/NOx as oxidant,respectively.In the La2-xKxNiMnO6 catalysts,the partial substitution of K at A-site leads to an increase of the concentrations of high valence cation and oxygen vacancy,which enhance the catalytic activity for soot combustion.The optimal substitution amount of K was equal to x=0.4 among these samples.Tp(peak temperature)in O2-TPO profile was 420-C and Tp in O2/NOx-TPO profile was 370-C over La1.6K0.4NiMnO6 catalyst for soot particulates combustion under loose contact conditions between catalyst and soot.展开更多
A novel porous coordination polymer [La(C8H6NO2)3]n was synthesized by hydrothermal reaction of flexible ligands 3 (3 pyridyl)acrylate and La(NO3)3· 6H2O. The structure was characterized by elemental analysis, IR...A novel porous coordination polymer [La(C8H6NO2)3]n was synthesized by hydrothermal reaction of flexible ligands 3 (3 pyridyl)acrylate and La(NO3)3· 6H2O. The structure was characterized by elemental analysis, IR spectroscopy and X ray single crystal diffraction. X ray single crystal analysis reveals the structure consists of [La(C8H6NO2)3]n. It crystallizes in monoclinic crystal system with space group P2(1)/c. Crystallographic date: a=0. 7889(3)nm, b=2.5916(9)nm, c=1.1489(4)nm, α =90.00° , β =95.219(6)° , γ =90.00° , V=2.3393(15)nm3, Z=4, Dc=1.656g· cm- 3, μ =1.871mm- 1, F(000)=1152, R1=0.0328, wR2=0.0522. CCDC: 211700.展开更多
文摘采用静电纺丝法制得La2Co Fe O6竹节状中空纳米纤维光催化材料。La2Co Fe O6纳米纤维具有稳定的一维结构,由菱形晶型的La2Co Fe O6纳米颗粒相互连接组成,并存在明显的竹节状中空结构,其比表面积可达98.7 m2/g。La2Co Fe O6纳米纤维对自然光具有较高的利用率,其禁带宽度为1.6 e V。在甲基橙溶液浓度为10 mg/L,p H为2,催化剂用量为1.5 g/L条件下,自然光光照2 h后,La2Co Fe O6纳米纤维对甲基橙的降解率可达96.9%。
基金supported by the National Natural Science Foundation of China(No.20603016)the Liaoning Provincial Science&Technology Project of China(No.20071074)
文摘Nanosized La2-xKxNiMnO6 catalysts with ABO3 type perovskite-like structure were prepared by auto-combustion method using citric acid as a ligand to control particle size and morphology.The structures and properties of these perovskite-like oxides were investigated by X-ray powder diffraction(XRD)and temperature-programmed reduction(TPR).The catalytic activities for soot combustion were evaluated by temperature- programmed oxidation(TPO)with pure O2 and O2/NOx as oxidant,respectively.In the La2-xKxNiMnO6 catalysts,the partial substitution of K at A-site leads to an increase of the concentrations of high valence cation and oxygen vacancy,which enhance the catalytic activity for soot combustion.The optimal substitution amount of K was equal to x=0.4 among these samples.Tp(peak temperature)in O2-TPO profile was 420-C and Tp in O2/NOx-TPO profile was 370-C over La1.6K0.4NiMnO6 catalyst for soot particulates combustion under loose contact conditions between catalyst and soot.
文摘A novel porous coordination polymer [La(C8H6NO2)3]n was synthesized by hydrothermal reaction of flexible ligands 3 (3 pyridyl)acrylate and La(NO3)3· 6H2O. The structure was characterized by elemental analysis, IR spectroscopy and X ray single crystal diffraction. X ray single crystal analysis reveals the structure consists of [La(C8H6NO2)3]n. It crystallizes in monoclinic crystal system with space group P2(1)/c. Crystallographic date: a=0. 7889(3)nm, b=2.5916(9)nm, c=1.1489(4)nm, α =90.00° , β =95.219(6)° , γ =90.00° , V=2.3393(15)nm3, Z=4, Dc=1.656g· cm- 3, μ =1.871mm- 1, F(000)=1152, R1=0.0328, wR2=0.0522. CCDC: 211700.
文摘为开发高性能车载NO_2气体传感器敏感电极材料,以La_2O_3和Sr、Fe、Ni的硝酸盐、柠檬酸和乙二醇为原料,在pH=8~9的碱性条件采用Pechini法合成了约80~90 nm的复合氧化物(La_(0.8)Sr_(0.2))_2FeNiO_(6-δ)(LSFN)双钙钛矿粉末材料,并对合成工艺中柠檬酸(CA)与金属阳离子(M)的配比进行了研究。采用丝网印刷将其制备成基于氧化钇稳定氧化锆(YSZ)的NO_2传感器的敏感电极。运用TG/DTA、XRD、FSEM和ESEM对粉末材料和敏感电极进行了表征,并研究了烧结温度对LSFN敏感电极的NO_2敏感性的影响。研究结果表明:适当的柠檬酸与金属阳离子(CA/M)配比可降低材料的成相温度。XRD测试结果表明,LSFN的结构对称性会被烧结温度改变。对不同温度下烧结的LSFN敏感电极在550℃下的NO_2敏感性测试结果表明,其敏感性受烧结温度的影响,不同烧结温度下敏感电极形态可调控其NO_2敏感性。1300℃烧结的LSFN敏感电极的传感器具有较好的三维网络结构和最薄的电极厚度,表现出最高的NO_2敏感性,其灵敏度高达130. 17 m V/decade。