Collaborative Innovation Centre of Henan Province for Green Manufacturing of Fine Chemicals, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, School of Chemistry and Chemical Engineering, Henan Normal University , Xinxiang, Henan 453007, PR China.
ACS Appl Mater Interfaces. 2017 May 17;9(19):16635-16643. doi: 10.1021/acsami.7b01874. Epub 2017 May 2.
This work developed a facile colloidal route to synthesize BH-capped PdAg nanoparticles (NPs) in water using the reducing ionic liquids of [Cmim]BH, and the resulting NPs were prone to form the nanocomposites with [amim]-modified reduced graphene (RG). The removal of the metal-free inorganic ions of BH can create the profoundly exposed interfaces on the PdAg NPs during the electrooxidation, and favor the ethanol oxidation reaction (EOR) in lowering energy barrier. The counterions of [Cmim] can gather ethanol, OH ions, and the reaction intermediates on catalysts, and synergistically interact with RG to facilitate the charge transfer in nanocomposites. The interface-modified RG nanosheets can effectively segregate the PdAg NPs from aggregation during the EOR. Along with the small size of 4.7 nm, the high alloying degree of 60.2%, the large electrochemical active surface area of 64.1 m g, and the great peak current density of 1501 mA cm mg, PdAg@[Cmim]BH-amimRG nanocomposite exhibits the low oxidation potentials, strong poison resistance, and stable catalytic activity for EOR in alkaline media, and hence can be employed as a promising anodic catalyst in ethanol fuel cells.
本工作开发了一种简便的胶体路线，使用还原型离子液体 [Cmim]BH 在水中合成 BH 封端的 PdAg 纳米颗粒 (NPs)，所得 NPs 易于与 [amim]-改性还原氧化石墨烯 (RG) 形成纳米复合材料。BH 中无金属无机离子的去除可在电氧化过程中在 PdAg NPs 上产生深刻暴露的界面，有利于降低能量势垒的乙醇氧化反应 (EOR)。[Cmim] 的抗衡离子可以在催化剂上聚集乙醇、OH 离子和反应中间体，并与 RG 协同相互作用以促进纳米复合材料中的电荷转移。界面改性的 RG 纳米片可有效防止 EOR 过程中 PdAg NPs 的聚集。PdAg@[Cmim]BH-amimRG 纳米复合材料具有 4.7nm 的小尺寸、60.2%的高合金化程度、64.1m^2 g^-1 的大电化学活性表面积和 1501mA cm^-2 mg^-1 的大峰值电流密度，表现出低氧化电位、强抗中毒性和在碱性介质中对 EOR 的稳定催化活性，因此可作为乙醇燃料电池中一种有前途的阳极催化剂。
