钙钛矿-凹凸棒石纳米复合材料光选择性催化氨还原脱硝

Preparation of La_(1-x)Ce_xNiO_3/Attapulgite Nanocomposite and Its Photo-Selective Catalytic Reduction for NO_x Removal

采用溶胶-凝胶法制备了La_(1-x)Ce_xNiO_3/凹凸棒石(ATP)复合材料。通过X射线衍射、透射电镜、Fourier变换红外光谱仪和紫外可见漫反射谱等方法对复合材料的结构、物化性质进行表征,并将其运用到光耦合脱硝中,探讨不同参数对氮氧化物去除率的影响。结果表明:载体凹凸棒石独特的孔道结构不仅可以增强对气体分子的吸附,还可以增强材料的光催化稳定性。当Ce^(3+)的掺杂量x为0.1时,La_(1-x)Ce_xNiO_3/ATP以固溶体的形式均匀分布在ATP表面,当掺杂量超过0.1时,有CeO_2相析出,与La_(1-x)Ce_xNiO_3在ATP表面形成异质结结构,当掺杂量为0.3时,复合材料的光催化活性最高,达到80%。

The Lal_xCexNiO3/attapulgite （ATP） nanocomposites were prepared via a sol-gel method. The structures and physiochemical properties were investigated by X-ray diffraction, transmission electron microscopy and UV-visible diffused reflectance spectroscopy, respectively. La1_xCexNiOJATP nanocomposite was used as a catalyst for photo-assisted selective catalytic reduction （photo-SCR） of NO~ under visible-light irradiation. The impact of Ce doping fraction on the NO conversion was investigated. The results indicate that Laz-xCexNiO3 solid solution is supported on the surface of ATP when x is 0.1. When x is greater than 0.1, CeO2 phase co-precipitates and forms well-defined ＂solid-solution/precipitation heterojunction＂ with Lal-xCexNiO3 on the surface of ATP. The photo-SCR activity of the composite material is the highest when x=0.3 and the NO conversion can reach 80% even at room temperature.