以纳米氧化石墨烯薄片(GO)为基础载体、N,N-二乙基乙二胺(ND)为改性剂,基于酰胺化反应合成GOND并作为稳定Pickering乳液的固体颗粒,以其为Pd负载的载体制备Pd/GOND,将其用于苯甲醇选择氧化制备苯甲醛反应。利用扫描电子显微镜(SEM)、红外光谱(FT-IR)、Zeta电位、X射线光电子能谱仪(XPS)等对GOND进行表征。结果表明,ND的修饰是乳化剂能够在油/水界面稳定吸附的主要原因,当GO/ND质量比为1/4时,材料在pH>7的环境下仍表现出高乳液稳定性。GOND在低质量浓度下(1mg/mL)即可稳定形成尺寸均匀(140 μm)的Pickering乳液。此外,Pd/GOND乳液催化剂可以有效提高苯甲醇的转化率,Pd/GO和Pd/GOND催化苯甲醇的转化率分别为0和76%。

GOND is synthesized through amidation reaction with graphene oxide nanosheets (GO) as a basic carrier and N,N-diethyl ethylenediamine (ND) as a modifier,and used as solid particles for stabilizing Pickering emulsion.GOND is used as a carrier for Pd to prepare Pd/GOND,which is used in the selective oxidation of benzyl alcohol to make benzaldehyde.The prepared GOND is characterized by means of SEM,FT-IR,zeta potential,and XPS.Results show that the ND modification is the main reason that the emulsifier is able to adsorb stably at the oil/water interface.The material still exhibits high emulsion stability at pH>7 when the mass ratio of GO to ND is 1∶4.GOND at a low mass concentration (1 mg·mL^-1) can be stabilized to form Pickering emulsion with uniform size (140 μm).In addition,the Pd/GOND emulsion catalyst can effectively improve the conversion of benzyl alcohol.The conversion rates of benzyl alcohol catalyzed by Pd/GO and Pd/GOND are 0% and 76%,respectively.

王泽波(1997-),男,硕士生,研究方向为乳液催化,wangzebo1108@link.tyut.edu.cn;单媛媛(1987-),女,博士,讲师,研究方向为乳液催化,通讯联系人,shanyuanyuan@tyut.edu.cn。