The homogeneously dispersed, less agglomerated YAG nanopowders are synthesized by the citrate-gel method followed by low-temperature self-propagating combustion reaction, using Y2O3, Al(NO3)3?9H2O and citric acid as s...The homogeneously dispersed, less agglomerated YAG nanopowders are synthesized by the citrate-gel method followed by low-temperature self-propagating combustion reaction, using Y2O3, Al(NO3)3?9H2O and citric acid as starting materials. This method effectively solves the problems caused by solid-state reaction at high temperature and the hard ag-glomerates brought by the chemical precipitation method. The powders are characterized by TG-DTA, XRD, FT-IR and TEM respectively. The experiments show that the forming temperature of YAG crystal phase is 850°C and the pseudo-YAG crystalline appears during the calcination and transforms to pure YAG at 1050°C. The powders with sizes less than 50 nm are observed by TEM micrography, which is consistent with the result calculated by Scherrer's formula. The powders consist of single grains.展开更多
以甘氨酸为络合剂,采用低温自蔓延燃烧法合成La和Nd共掺杂Bi Fe O_(3)(Bi_(0.9-x)La_(0.1)Nd_xFe O_(3),x=0.1,0.2,0.3,0.4,at%)陶瓷粉体,利用X射线衍射(XRD)、漫反射光谱(DRS)、扫描电镜(SEM)和傅里叶红外光谱(FT-IR)等技术分析产物的...以甘氨酸为络合剂,采用低温自蔓延燃烧法合成La和Nd共掺杂Bi Fe O_(3)(Bi_(0.9-x)La_(0.1)Nd_xFe O_(3),x=0.1,0.2,0.3,0.4,at%)陶瓷粉体,利用X射线衍射(XRD)、漫反射光谱(DRS)、扫描电镜(SEM)和傅里叶红外光谱(FT-IR)等技术分析产物的相组成和微观结构。结果表明:与传统固相反应法相比,低温自蔓延燃烧法的合成温度大幅降低到600℃。当La和Nd元素的掺杂量不高于30 at%时,合成的陶瓷粉体为单一的四方钙钛矿结构,固溶极限有所提高。600℃煅烧2 h所得产物的颗粒平均尺寸约为27 nm,且分散性良好。La和Nd共掺杂可以有效降低Bi Fe O_(3)的禁带宽度,提高可见光的利用率。采用低温自蔓延合成的La和Nd共掺杂Bi Fe O_(3)在铁电陶瓷和光催化材料方面具有一定的应用价值。展开更多
基金This work is financially supported by the Excellent Teachers Fund by the Ministry of Education of China (No. KB200226).
文摘The homogeneously dispersed, less agglomerated YAG nanopowders are synthesized by the citrate-gel method followed by low-temperature self-propagating combustion reaction, using Y2O3, Al(NO3)3?9H2O and citric acid as starting materials. This method effectively solves the problems caused by solid-state reaction at high temperature and the hard ag-glomerates brought by the chemical precipitation method. The powders are characterized by TG-DTA, XRD, FT-IR and TEM respectively. The experiments show that the forming temperature of YAG crystal phase is 850°C and the pseudo-YAG crystalline appears during the calcination and transforms to pure YAG at 1050°C. The powders with sizes less than 50 nm are observed by TEM micrography, which is consistent with the result calculated by Scherrer's formula. The powders consist of single grains.
文摘以甘氨酸为络合剂,采用低温自蔓延燃烧法合成La和Nd共掺杂Bi Fe O_(3)(Bi_(0.9-x)La_(0.1)Nd_xFe O_(3),x=0.1,0.2,0.3,0.4,at%)陶瓷粉体,利用X射线衍射(XRD)、漫反射光谱(DRS)、扫描电镜(SEM)和傅里叶红外光谱(FT-IR)等技术分析产物的相组成和微观结构。结果表明:与传统固相反应法相比,低温自蔓延燃烧法的合成温度大幅降低到600℃。当La和Nd元素的掺杂量不高于30 at%时,合成的陶瓷粉体为单一的四方钙钛矿结构,固溶极限有所提高。600℃煅烧2 h所得产物的颗粒平均尺寸约为27 nm,且分散性良好。La和Nd共掺杂可以有效降低Bi Fe O_(3)的禁带宽度,提高可见光的利用率。采用低温自蔓延合成的La和Nd共掺杂Bi Fe O_(3)在铁电陶瓷和光催化材料方面具有一定的应用价值。
