通过非水解途径在超临界二氧化碳中合成二氧化钛光催化剂。

Synthesis of TiO2 photocatalysts in supercritical CO2 via a non-hydrolytic route.

作者信息

Guo Guangqing, Whitesell James K, Fox Marye Anne

机构信息

Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27606, USA.

出版信息

J Phys Chem B. 2005 Oct 13;109(40):18781-5. doi: 10.1021/jp0530101.

DOI:10.1021/jp0530101

PMID:16853417

Abstract

Nanoscaled TiO2 powders with narrow size dispersion were prepared in supercritical carbon dioxide via non-hydrolytic acylation/deacylation of titanium alkoxide precursors with or without tris-fluorination. The microstructures of these powders were characterized by spectroscopic (FTIR, TGA, and XRD), microscopic (SEM or TEM), and surface area (BET) measurements. Photocatalytic oxidation of 1-octanol on these calcined TiO2 powders and on commercial T805 TiO2 suspended in aerated supercritical carbon dioxide revealed relative reactivity controlled by the powder microstructures. Calcined TiO2 prepared from titanium(IV) isopropoxide and trifluoroacetic anhydride was effectively dispersed in aerated supercritical carbon dioxide under stirring and exhibited high photocatalytic oxidation activity.

摘要

通过钛醇盐前体的非水解酰化/脱酰化反应，在有或没有三氟化的情况下，于超临界二氧化碳中制备了具有窄尺寸分散性的纳米级二氧化钛粉末。通过光谱（傅里叶变换红外光谱、热重分析和X射线衍射）、显微镜（扫描电子显微镜或透射电子显微镜）和表面积（比表面积测定法）测量对这些粉末的微观结构进行了表征。在这些煅烧的二氧化钛粉末以及悬浮在充气超临界二氧化碳中的商用T805二氧化钛上，1-辛醇的光催化氧化显示出由粉末微观结构控制的相对反应活性。由异丙醇钛和三氟乙酸酐制备的煅烧二氧化钛在搅拌下有效地分散在充气超临界二氧化碳中，并表现出高光催化氧化活性。