Aluminum titanate has been widely used in low expansion applications and its thermal stability has been a hot topic. The stability of aluminium titanate research for improving product quality, and expanding its applic...Aluminum titanate has been widely used in low expansion applications and its thermal stability has been a hot topic. The stability of aluminium titanate research for improving product quality, and expanding its application field is of great significance. Aluminum titanate as glass melt erosion resistance and high temperature resistant, can be applied to high temperature pigment base. The medium temperature stability of aluminum titanate can be improved by ion doping, and magnesium stability of aluminum titanate has been widely studied. Therefore aluminium titanate is expected to become an ideal high temperature ceramic base material. In this paper, the preparation technology of magnesium-stabilized aluminum titanate powder was reviewed, and the preparation of magnesium-stabilized aluminum titanate powder by non-hydrolyzed sol-gel was mainly introduced.展开更多
The simultaneous control of crystal phase stability and one-dimensional growth has always been the major challenge for the preparation of tetragonal zirconia whiskers.In this study,we report a facile molten salt proce...The simultaneous control of crystal phase stability and one-dimensional growth has always been the major challenge for the preparation of tetragonal zirconia whiskers.In this study,we report a facile molten salt processing that utilizes CaF_(2) as a stabilizer and adsorbent to meet the phase and morphology requirements.The processes of stabilization,phase transition,ion adsorption and formation of special morphology involved in zirconia growth were investigated by XRD,IR,SEM,DTA-TG and TEM.By controlling the amount of CaF_(2)(15 wt%)added in the reaction precursor,tetragonal zirconia whiskers with a desired aspect ratio(>16)can be synthesized,which show single crystalline nature and[001]preferred direction.Ca ions doped at low temperature inhibit the occurrence of phase transition,which allows the tetragonal structure to be retained to room temperature.The inducement and pattern of whisker growth are supposed to be F-adsorption and screw dislocation elongation,respectively.The specific selectivity of surface adsorbed ions to certain zirconia crystal planes reduces or even inhibits the epitaxial growth rate in this direction,offering a viable avenue for the morphology modulation of inorganic nanomaterials.展开更多
CeO2 nanosheets were directly synthesized by a precipitation process with the aid of 1-butyl-3-methyl-imidazolium ionic liquids at room temperature. The anion species and the concentration of the room temperature ioni...CeO2 nanosheets were directly synthesized by a precipitation process with the aid of 1-butyl-3-methyl-imidazolium ionic liquids at room temperature. The anion species and the concentration of the room temperature ionic liquids (RTILs) have a great influence on the morphology of the resulting products. The as-prepared CeO2 is irregular and agglomerated seriously in the absence of RTILs, while it changes from nanocube to nanosheet with increasing the RTIL concentration or decreasing the polarity and hydrophilicity in the orders [Bmim] Cl > [Bmim] Br > [Bmim] BF4 > [Bmim] PF6. The CeO2 nanocubes have relatively uniform grain size distribution with size of 4.5-6.4 nm, and the nanosheets are assembled by a great deal of nanocrystalline whose length and width extend to hundreds of nanometers. The as-synthesized CeO2 exhibits an excellent removal capacity for the organic pollutant Congo red dye, indicating its potential use in practical wastewater treatment.展开更多
文摘Aluminum titanate has been widely used in low expansion applications and its thermal stability has been a hot topic. The stability of aluminium titanate research for improving product quality, and expanding its application field is of great significance. Aluminum titanate as glass melt erosion resistance and high temperature resistant, can be applied to high temperature pigment base. The medium temperature stability of aluminum titanate can be improved by ion doping, and magnesium stability of aluminum titanate has been widely studied. Therefore aluminium titanate is expected to become an ideal high temperature ceramic base material. In this paper, the preparation technology of magnesium-stabilized aluminum titanate powder was reviewed, and the preparation of magnesium-stabilized aluminum titanate powder by non-hydrolyzed sol-gel was mainly introduced.
基金supported by the National Natural Science Foundation of China[grant numbers 51662016,51962014,52072162]the Key Research and Development Program of Jiangxi Province,China[grant number 20192BBEL50022]+3 种基金the Key projects of Youth Fund of Jiangxi Province,China[grant number 20202ACBL214006,20202ACBL214008]the Key Science Foundation of Jiangxi Provincial Department of Education,China[grant number GJJ180699]the Scientific Research Fund of Jiangxi Provincial Education Department(grant number GJJ160881)the Youth Science Foundation of Jiangxi Provincia Department of Education,China[grant number GJJ180740]。
文摘The simultaneous control of crystal phase stability and one-dimensional growth has always been the major challenge for the preparation of tetragonal zirconia whiskers.In this study,we report a facile molten salt processing that utilizes CaF_(2) as a stabilizer and adsorbent to meet the phase and morphology requirements.The processes of stabilization,phase transition,ion adsorption and formation of special morphology involved in zirconia growth were investigated by XRD,IR,SEM,DTA-TG and TEM.By controlling the amount of CaF_(2)(15 wt%)added in the reaction precursor,tetragonal zirconia whiskers with a desired aspect ratio(>16)can be synthesized,which show single crystalline nature and[001]preferred direction.Ca ions doped at low temperature inhibit the occurrence of phase transition,which allows the tetragonal structure to be retained to room temperature.The inducement and pattern of whisker growth are supposed to be F-adsorption and screw dislocation elongation,respectively.The specific selectivity of surface adsorbed ions to certain zirconia crystal planes reduces or even inhibits the epitaxial growth rate in this direction,offering a viable avenue for the morphology modulation of inorganic nanomaterials.
基金National Natural Science Foundation of China，the Projects of Jiangxi Provincial Department of Science and Technology，the Science Foundation of Jiangxi Provincial Department of Education
文摘CeO2 nanosheets were directly synthesized by a precipitation process with the aid of 1-butyl-3-methyl-imidazolium ionic liquids at room temperature. The anion species and the concentration of the room temperature ionic liquids (RTILs) have a great influence on the morphology of the resulting products. The as-prepared CeO2 is irregular and agglomerated seriously in the absence of RTILs, while it changes from nanocube to nanosheet with increasing the RTIL concentration or decreasing the polarity and hydrophilicity in the orders [Bmim] Cl > [Bmim] Br > [Bmim] BF4 > [Bmim] PF6. The CeO2 nanocubes have relatively uniform grain size distribution with size of 4.5-6.4 nm, and the nanosheets are assembled by a great deal of nanocrystalline whose length and width extend to hundreds of nanometers. The as-synthesized CeO2 exhibits an excellent removal capacity for the organic pollutant Congo red dye, indicating its potential use in practical wastewater treatment.
