A few-layer graphene-graphene oxide composite containing nanodiamonds as metal-free catalysts

作者：Tung Tran Thanh; Ba Housseinou; Lai Truong Phuoc; Nhut Jean Mario; Ersen Ovidiu; Begin Dominique; Janowska Izabela; Dinh Lam Nguyen; Granger Pascal; Cuong Pham Huu^*

来源：Journal of Materials Chemistry A, 2014, 2(29): 11349-11357.

DOI：10.1039/c4ta01307g

We report a high yield exfoliation of few-layer-graphene (FLG) with up to 17% yield from expanded graphite, under 5 h sonication time in water, using graphene oxide (GO) as a surfactant. The aqueous dispersion of GO attached FLG (FLG-GO), with less than 5 layers, is used as a template for further decoration of nanodiamonds (NDs). The hybrid materials were self-organized into 3D-laminated nanostructures, where spherical NDs with a diameter of 4-8 nm are homogeneously distributed on the surface of the FLG-GO complex (referred to as FLG-GO@NDs). It was found that GO plays a dual role, it (1) mediated exfoliation of expanded graphite in aqueous solution resulting in a FLG-GO colloid system, and (2) incorporated ND particles for the formation of composites. A high catalytic performance in the dehydrogenation of ethylbenzene on FLG-GO@ND metal-free catalyst is achieved; 35.1% of ethylbenzene conversion and 98.6% styrene selectivity after a 50 h reaction test are observed which correspond to an activity of 896 mmol(ST) g(catalyst)(-1) h(-1), which is 1.7 and 5 times higher than those of the unsupported NDs and traditional catalysts, respectively. The results demonstrate the potential of the FLG-GO@ND composite as a promising catalyst for steam-free industrial dehydrogenation applications.

• 出版日期2014