用传统的固相反应烧结法制备了(1-xmol%)BaTi03-xm01%(Bi0.5Na0.5)TiO3(BBNTx)高温无铅正温度系数电阻(positive temperature coefficient of resistivity,PTCR)陶瓷。x射线衍射表明所有的BBNTx陶瓷形成了单一的四方钙钛矿...用传统的固相反应烧结法制备了(1-xmol%)BaTi03-xm01%(Bi0.5Na0.5)TiO3(BBNTx)高温无铅正温度系数电阻(positive temperature coefficient of resistivity,PTCR)陶瓷。x射线衍射表明所有的BBNTx陶瓷形成了单一的四方钙钛矿结构。SEM分析结果显示随着BNT含量的增加,陶瓷晶粒尺寸减小。空气中烧结的0.2mol%Nb掺杂的BBNT1陶瓷,室温电阻率为~102^Ω·cm,电阻突跳为~4.5个数量级,居里温度为~150℃。氮气中烧结的0.3m01%Nb掺杂的BBNh(10≤x≤60)陶瓷,同样具有明显的PTCR效应,居里温度在180~235℃之间。随着BNT含量的增加,材料的室温电阻率增大,同时陶瓷的电阻突跳比下降。展开更多
A three-dimensional(3D) barium complex with 1,3,5-benzenetricarboxylic acid(H3BTC), {[Ba1.5(BTC)(H2O)]·(H2O)}n(1), was synthesized in DMF/EtOH/H2O mixed solution under solvothermal conditions, and cha...A three-dimensional(3D) barium complex with 1,3,5-benzenetricarboxylic acid(H3BTC), {[Ba1.5(BTC)(H2O)]·(H2O)}n(1), was synthesized in DMF/EtOH/H2O mixed solution under solvothermal conditions, and characterized by single-crystal X-ray diffraction, elemental analyses, IR spectra, thermogravimetric analyses, and photoluminescence measurement. In complex 1, the 2D I2O0 type inorganic layer is constructed by {Ba1O10} and {Ba2O9} polyhedra. Moreover, the solid-state fluorescence measurement reveals a fluorescence emission band at 465 nm under 344 nm excitation, assigned to a charge-transfer transition.展开更多
文摘用传统的固相反应烧结法制备了(1-xmol%)BaTi03-xm01%(Bi0.5Na0.5)TiO3(BBNTx)高温无铅正温度系数电阻(positive temperature coefficient of resistivity,PTCR)陶瓷。x射线衍射表明所有的BBNTx陶瓷形成了单一的四方钙钛矿结构。SEM分析结果显示随着BNT含量的增加,陶瓷晶粒尺寸减小。空气中烧结的0.2mol%Nb掺杂的BBNT1陶瓷,室温电阻率为~102^Ω·cm,电阻突跳为~4.5个数量级,居里温度为~150℃。氮气中烧结的0.3m01%Nb掺杂的BBNh(10≤x≤60)陶瓷,同样具有明显的PTCR效应,居里温度在180~235℃之间。随着BNT含量的增加,材料的室温电阻率增大,同时陶瓷的电阻突跳比下降。
基金Supported by the Fundamental Research Funds for the Central Universities(13CX02006A,14CX02158A)the scientific research foundation of Shandong province Outstanding Young Scientist Award(BS2011CL041)Natural Science Foundation of Shandong Province(ZR2010BL011)
文摘A three-dimensional(3D) barium complex with 1,3,5-benzenetricarboxylic acid(H3BTC), {[Ba1.5(BTC)(H2O)]·(H2O)}n(1), was synthesized in DMF/EtOH/H2O mixed solution under solvothermal conditions, and characterized by single-crystal X-ray diffraction, elemental analyses, IR spectra, thermogravimetric analyses, and photoluminescence measurement. In complex 1, the 2D I2O0 type inorganic layer is constructed by {Ba1O10} and {Ba2O9} polyhedra. Moreover, the solid-state fluorescence measurement reveals a fluorescence emission band at 465 nm under 344 nm excitation, assigned to a charge-transfer transition.