Nd-doped(2%,5%,10% in mass ratio) SnO2 powders were prepared via a facile hydrothermal procedure.The as-prepared samples were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),and Brunauer-Emme...Nd-doped(2%,5%,10% in mass ratio) SnO2 powders were prepared via a facile hydrothermal procedure.The as-prepared samples were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),and Brunauer-Emmett-Teller(BET) specific surface area analyzers.Results showed that the Nd-doped SnO2 samples had more uniform and smaller primary particles compared with the pure sample,the particle size of the doped SnO2 decreased gradually with the increase of Nd,and the specific surface area also increased with the increase of the doped Nd.When used as gas sensing materials,the 5% and 10% Nd-doped sample showed high sensitivity and selectivity to ethanol.Furthermore,the Nd-doped sample showed fast response and recovery time to ethanol gas.This could be attributed to their small diameter,large surface area and Nd element doping.展开更多
以 Sn Cl4· Ti( OBu) 4、氨水、乙醇为原料 ,采用活性层包覆法 ,制备出 Ti O2 / Sn O2 复合光催化剂 ,并用IR、XRD、TEM和 BET等手段对样品进行了表征 .研究其对有机磷农药敌敌畏的光催化降解效果 ,与单一半导体催化剂 Sn O2 、Ti ...以 Sn Cl4· Ti( OBu) 4、氨水、乙醇为原料 ,采用活性层包覆法 ,制备出 Ti O2 / Sn O2 复合光催化剂 ,并用IR、XRD、TEM和 BET等手段对样品进行了表征 .研究其对有机磷农药敌敌畏的光催化降解效果 ,与单一半导体催化剂 Sn O2 、Ti O2 做了简单对比 .结果表明 :所制 Ti O2 / Sn O2 样品为包覆型结构 ,由锐钛矿型 Ti O2 金红石型 Sn O2 组成 ,与 Sn O2 及 Ti O2 晶体粉末相比所制 Ti O2 / Sn O2 包覆粒子光催化活性得到明显提高 .展开更多
利用直流电弧等离子体蒸发 -凝聚法制备 Sn O2 纳米粒子 ,研究了 Sn O2 粒子在等离子体焰流中的形成和生长机理 ,探讨了等离子体发生器功率、气体配比和冷却介质对 Sn O2 纳米粒子粒度和纯度的影响 ,制备出了纯度大于98.8%、粒度可控的 ...利用直流电弧等离子体蒸发 -凝聚法制备 Sn O2 纳米粒子 ,研究了 Sn O2 粒子在等离子体焰流中的形成和生长机理 ,探讨了等离子体发生器功率、气体配比和冷却介质对 Sn O2 纳米粒子粒度和纯度的影响 ,制备出了纯度大于98.8%、粒度可控的 Sn O2 纳米粉末 ,为制造高性能 Sn O2 气敏传感器打下了良好的基础。展开更多
TiO 2 nanoparticles were obtained from industrial TiOSO 4 by hydrolysis method. SnO 2/TiO 2 and SnO 2-TiO 2 composite powders were prepared by stepwise precipitation method and coating method, respectively. The phase ...TiO 2 nanoparticles were obtained from industrial TiOSO 4 by hydrolysis method. SnO 2/TiO 2 and SnO 2-TiO 2 composite powders were prepared by stepwise precipitation method and coating method, respectively. The phase transformation of TiO 2 and the effect of composite mode of SnO 2 on phase transformation of TiO 2 have been investigated by TG-DTA and XRD. The phase transform of pure TiO 2 from anatase to rutile begins at 750 ℃ and the presence of SnO 2 markedly reduces the transform temperature: for coated SnO 2-TiO 2 composite with ω(SnO 2)=20% it was 400 ℃. The SnO 2/TiO 2 composite prepared by precipitation method and followed by calcination at 400 ℃ for 30 min possesses 55% rutile TiO 2. The formation of SnO 2-TiO 2 solid- solution occurrs mainly due to the substitution of Ti 4+ crystal lattice sites by Sn 4+ ions of SnO 2.展开更多
基金Project supported by the National Natural Science Foundation of China (20871107)He'nan Outstanding Youth Science Fund (0612002700)the Natural Science Foundation of the Education Department of Henan Province (2009A150031)
文摘Nd-doped(2%,5%,10% in mass ratio) SnO2 powders were prepared via a facile hydrothermal procedure.The as-prepared samples were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),and Brunauer-Emmett-Teller(BET) specific surface area analyzers.Results showed that the Nd-doped SnO2 samples had more uniform and smaller primary particles compared with the pure sample,the particle size of the doped SnO2 decreased gradually with the increase of Nd,and the specific surface area also increased with the increase of the doped Nd.When used as gas sensing materials,the 5% and 10% Nd-doped sample showed high sensitivity and selectivity to ethanol.Furthermore,the Nd-doped sample showed fast response and recovery time to ethanol gas.This could be attributed to their small diameter,large surface area and Nd element doping.
文摘以 Sn Cl4· Ti( OBu) 4、氨水、乙醇为原料 ,采用活性层包覆法 ,制备出 Ti O2 / Sn O2 复合光催化剂 ,并用IR、XRD、TEM和 BET等手段对样品进行了表征 .研究其对有机磷农药敌敌畏的光催化降解效果 ,与单一半导体催化剂 Sn O2 、Ti O2 做了简单对比 .结果表明 :所制 Ti O2 / Sn O2 样品为包覆型结构 ,由锐钛矿型 Ti O2 金红石型 Sn O2 组成 ,与 Sn O2 及 Ti O2 晶体粉末相比所制 Ti O2 / Sn O2 包覆粒子光催化活性得到明显提高 .
文摘利用直流电弧等离子体蒸发 -凝聚法制备 Sn O2 纳米粒子 ,研究了 Sn O2 粒子在等离子体焰流中的形成和生长机理 ,探讨了等离子体发生器功率、气体配比和冷却介质对 Sn O2 纳米粒子粒度和纯度的影响 ,制备出了纯度大于98.8%、粒度可控的 Sn O2 纳米粉末 ,为制造高性能 Sn O2 气敏传感器打下了良好的基础。
文摘TiO 2 nanoparticles were obtained from industrial TiOSO 4 by hydrolysis method. SnO 2/TiO 2 and SnO 2-TiO 2 composite powders were prepared by stepwise precipitation method and coating method, respectively. The phase transformation of TiO 2 and the effect of composite mode of SnO 2 on phase transformation of TiO 2 have been investigated by TG-DTA and XRD. The phase transform of pure TiO 2 from anatase to rutile begins at 750 ℃ and the presence of SnO 2 markedly reduces the transform temperature: for coated SnO 2-TiO 2 composite with ω(SnO 2)=20% it was 400 ℃. The SnO 2/TiO 2 composite prepared by precipitation method and followed by calcination at 400 ℃ for 30 min possesses 55% rutile TiO 2. The formation of SnO 2-TiO 2 solid- solution occurrs mainly due to the substitution of Ti 4+ crystal lattice sites by Sn 4+ ions of SnO 2.
