氧化石墨烯/类水滑石基复合催化剂的可控制备及其催化性能

针对纳米催化剂在有机染料氧化降解反应中存在的问题,开发高效纳米Fe基催化剂成为当前研究的重点。基于"创新纳米结构调变催化功能"的新策略,利用类水滑石层板金属离子和层间阴离子与氧化石墨烯(GO)表面官能团之间的静电作用,采用水热法制备氧化石墨烯复合类水滑石Fe-LDH@GO纳米催化剂。利用XRD、N_2吸附-脱附和TEM对催化剂的形貌、尺寸、孔道及FeO_x粒子尺寸等物化性质进行表征,发现氧化石墨烯的引入不改变水滑石纳米片结构和形貌,但能够增加催化剂的比表面积,有效锚定FeO_x纳米粒子,使其粒径减小并均匀分散在载体表面,提供更多的有效活性位点。XPS结果表明,催化剂表面存在的Fe^(2+)是芬顿反应的活性中心,氧化石墨烯的引入提高含氧官能团数量,使其在RhB降解反应中表现出优异的催化活性,反应14 min时,RhB转化率100%。

Controllable preparation and catalytic performance of grapheme oxide/hydrotalcite based composite catalysts

New and efficient Fe-based nanocatalyst development is urgently desired due to problems of nanocatalyst for organic dyes oxidative degradation reactions.It still remains a big challenge.Herein,based on new strategy of innovated the catalytic function of nanostructures,new types of LDH@GO catalysts were prepared by the hydrothermal method considering the electrostatic interaction between the hydrotalcite interlayer metal anion and the surface functional group of graphene oxide(GO).The physicochemical properties of the catalyst such as morphology,size,pore volume and FeO_x particle size were characterized by XRD,N₂ adsorption-desorption and TEM.It was found that the introduction of GO did not change the structure and morphology of the hydrotalcite nanosheets.It could increase the specific surface area of LDH@GO catalysts,and anchor FeO_x nanoparticles effectively to decrease particle size and disperse highly on support surface,which provided more effective active sites.XPS results showed that Fe²⁺ on the catalyst surface were major active site for the Fenton reaction.The introduction of GO increased the number of oxygen-containing functional groups which resulted in excellent catalytic performance for the RhB degradation.Conversion was 100% within 14 minutes of reation time.