Yu et al. Nanoscale Research Letters 2012, 7:234 http://www.nanoscalereslett.com/content/7/1/234 N A N O E X P R E S S Open Access Fabrication of palladium/graphene oxide composite by plasma reduction at room temperature Yue Yu, Yingzhi Li, Yunxiang Pan and Chang-jun Liu* Abstract Pd nanoparticles were fabricated on graphene oxide (GO) using a deposition-precipitation method with a glow discharge plasma reduction at room temperature. Argon was employed as the plasma-generating gas. The novel plasma method selectively reduces the metal ions. The graphene oxide has no change with this plasma reduction according to the Fourier transform infrared analysis. The Pd nanoparticles on the GO were uniformly distributed with an average diameter of 1.6 nm. The functional groups on the GO not only prevent Pd nanoparticles from further aggregation but also provide a strong hydrophilic property to the Pd/GO composite, which can form stable colloidal dispersions in water. Keywords: Nanoparticles, Composite materials, Palladium, Graphene oxide, Glow discharge, Plasma Background Graphene oxide (GO) is a highly oxidized layered gra- phene-based material with a large surface area and var- ious functional groups such as -OH, -COOH, etc. [1-4]. These functional groups are chemically active so that GO can be decorated by various substances including biomolecules, metals and metal oxides [3,5,6]. GO can also be well dispersed in aqueous solutions due to the hydrophilic functional groups. The high solubility in water makes GO an ideal substrate for catalysts in water phase reactions. However, it is a challenge to reduce metal precursors on GO because GO is easily reduced with conventional reduction using NaBH4, N2H4 and ethylene glycol or irradiation method (microwave and laser pulse). Here, we present a new fabrication method of Pd/GO composites using the room temperature glow discharge plasma reduction, which has been demonstrated to be a good strategy to reduce noble metal ions into nanoparti- cles [7-11]. The glow discharge plasma was shown not to affect the GO substrate. In order to maximize the loading efficiency and achieve high dispersion of Pd metal, deposition-precipitation was also carried out to * Correspondence: ughg_cjl@yahoo.com Advanced Nano Technology Center, School of Chemical Engineering and Technology, Tianjin University, 300072 Tianjin, China anchor Pd precursor onto GO before the plasma reduction. Methods GO was prepared by a modified Hummers method. Pd/ GO composites were prepared by deposition of palla- dium hydroxide from hydrolysis of palladium chloride at pH 4 to approximately 10. In a typical synthesis, 4 mL aqueous solution of H2PdCl4 (1 × 10-3 mol/L) was mixed with 4 mL aqueous solution of GO (1 mg/mL). NaOH (1 mol/L aqueous solution) was used to adjust the pH value of the H2PdCl4 and GO mixture. Then, the mixture was aged for 24 h before glow discharge plasma reduction. The details of glow discharge plasmas have been described previously [7,8]. The morphology of the sample was observed by trans- mission electron microscopy (TEM) and atomic force microscopy (AFM). TEM images were recorded with a Philips TECNAI G2F20 (Philips, Amsterdam, The Neth- erlands) system. AFM tests were performed by a Veeco Multimode Microscope V (Veeco Instruments Inc., Plainview, NY, USA) with spin coating of the sample on freshly cleaved mica substrates. The Fourier transform infrared (FT-IR) spectra were recorded using a Bruker Tensor 27 (Bruker Optics, Ettlingen, Germany) spectro- meter with a resolution of 4 cm-1. © 2012 Yu et al; licensee Springer. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.