Optical Materials ( IF 3.9 ) Pub Date : 2021-02-26 , DOI: 10.1016/j.optmat.2021.110913 Kun Jiang , Jin Zhang , Yingfei Wan , Zengjian Liu , Jinwei Chen
In order to obtain the advanced photocatalyst with high performance for removing the gaseous formaldehyde, a new strategy with amination of titanium dioxide (TiO2) and combination with reduced graphene oxide (rGO) is proposed in this work. TiO2 was first aminated into amino-TiO2 and then combined with rGO by an electrostatic self-assembly process to form the amino-TiO2/rGO photocatalysts. The structure and morphology were characterized by XRD, FTIR, and SEM, respectively. Physicochemical properties were measured by EIS, XPS, ESR, PL, and photocurrent measurements. The mechanism of the photocatalytic reaction was studied. Optimal amino-TiO2/rGO catalyst exhibits high catalytic activity and recyclability. The reaction rate constant of HCHO over this catalyst is approximately 9.8 × 10−3 L mol−1 ·min−1, which is 10.5 times higher than that of the commercial Degussa P25 TiO2. The analysis results from XPS and ESR indicates that the high catalytic activity could be mainly attributed to the imine formed by chemisorption of amino and HCHO. The reaction speed of formaldehyde photolysis increases as the concentration of HCHO on the photocatalyst surface increased. In addition, the introduction of graphene enhances carrier separation efficiency so that leads to more reactive radicals such as hydroxyl radicals (·OH) and superoxide radicals (·O2−), leading to improved performance on formaldehyde photolysis. This could provide a useful method for highly efficient formaldehyde photocatalysis.
中文翻译:
TiO2 / rGO复合材料中二氧化钛的胺化对室温下光催化去除气态甲醛的影响
为了获得高性能的去除气态甲醛的高性能光催化剂,本工作提出了一种新的策略,即二氧化钛(TiO 2)的胺化和还原型氧化石墨烯(rGO)的结合。首先将TiO 2胺化为氨基TiO 2,然后通过静电自组装方法与rGO结合形成氨基TiO 2 / rGO光催化剂。分别用XRD,FTIR和SEM对结构和形貌进行表征。通过EIS,XPS,ESR,PL和光电流测量来测量理化性质。研究了光催化反应的机理。最佳氨基TiO 2/ rGO催化剂具有很高的催化活性和可回收性。HCHO在该催化剂上的反应速率常数约为9.8×10 -3 L mol -1 ·min -1,比市售Degussa P25 TiO 2高10.5倍。XPS和ESR的分析结果表明,高催化活性主要归因于氨基和HCHO的化学吸附形成的亚胺。甲醛光解的反应速度随着光催化剂表面上HCHO浓度的增加而增加。此外,引入的石墨烯提高载体的分离效率,从而导致更多的活性基团如羟基自由基(·OH)和超氧自由基(·O2 2 -),从而改善了甲醛的光解性能。这可以提供用于高效甲醛光催化的有用方法。