溶胶凝胶-离子交换法制备具有可见光活性介孔AgInO2光催化剂

Visible-light-driven photocatalytic activity of mesoporous AgInO2 synthesized by sol-gel combined ion exchange

摘要:

具有可见光响应高效光催化剂的设计和制备是环境与能源光催化研究领域的前沿和热点之一。本文采用溶胶凝胶-离子交换法制备AgInO₂介孔纳米材料,利用热分析(TGA-DSC)、X-射线衍射(XRD)、场发射扫描电镜(FESEM)、N₂吸附脱附以及紫外-可见吸收光谱等测试手段,研究了制备条件对AgInO₂微观结构的影响因素,并以甲醛为目标降解物研究了AgInO₂在可见光条件下光催化性能。研究结果表明：制备的介孔AgInO₂具有铜铁矿结构的晶型,颗粒尺寸约200-500纳米,N₂吸附脱附非等温曲线呈IV型,吸收边位于500-600 nm可见光范围内,在可见光照射180 min 的条件下,介孔AgInO₂对甲醛的光催化降解率达93.97%。本研究为介孔AgInO₂光催化剂在净化室内空气的广泛应用奠定了实验基础。

Abstract:

Design and fabrication of highly active photocatalysts under visible light irradiation are one of hotspots in the field of photocatalysis. In this paper, mesoporous AgInO₂ nanostructures have been synthesized through a combined sol-gel and ion exchange process. Thermogravimetric analysis-differential scanning calorimeter (TGA-DSC), X-ray diffraction analysis (XRD), field emission scanning electron microscopy (FESEM), N₂ adsorption-desorption and ultraviolet-visible (UV-vis) analysis technologies are used to investigate the effects of preparation condition on the microstructure of the AgInO₂. The photocatalytic performances have been evaluated by degradation of the formaldehyde under visible light irradiation. The results demonstrate that the mesoporous AgInO₂ is a delafossite structure with the uniform size about 200-500 nm and nitrogen adsorption- desorption type IV isotherms, the absorption edge of AgInO₂ lies between 500nm and 600 nm in the visible light scope. As-synthesized AgInO₂ exhibited remarkably high photocatalytic activity of 93.97% in decomposing formaldehyde for 180 min. These results provide a basic experimental process for preparation novel photocatalyst of AgInO₂, which will possess a broad prospect in terms of the applications in improving indoor air quality.