Department of Chemistry, Xavier University of Louisiana, New Orleans, LA 70125, USA.
Department of Physics &Engineering, Frostburg State University, Frostburg, MD 21532-2303, USA.
Sci Rep. 2016 Sep 21;6:33127. doi: 10.1038/srep33127.
Durable, highly efficient, and economic sound electrocatalysts for CO electrooxidation (COE) are the emerging key for wide variety of energy solutions, especially fuel cells and rechargeable metal-air batteries. Herein, we report the novel system of nickel-aluminum double layered hydroxide (NiAl-LDH) nanoplates on carbon nanotubes (CNTs) network. The formulation of such complexes system was to be induced through the assistance of gold nanoparticles in order to form dual-metal active sites so as to create a extended Au/NiO two phase zone. Bis (trifluoromethylsulfonyl)imide (NTf2) anion of ionic liquid electrolyte was selected to enhance the CO/O2 adsorption and to facilitate electro-catalyzed oxidation of Ni (OH)2 to NiOOH by increasing the electrophilicity of catalytic interface. The resulting neutral catalytic system exhibited ultra-high electrocatalytic activity and stability for CO electrooxidation than commercial and other reported precious metal catalysts. The turnover frequency (TOF) of the LDH-Au/CNTs COE catalyst was much higher than the previous reported other similar electrocatalysts, even close to the activity of solid-gas chemical catalysts at high temperature. Moreover, in the long-term durability testing, the negligible variation of current density remains exsisting after 1000 electrochemistry cycles.
用于 CO 电氧化 (COE) 的耐用、高效且经济的电催化剂是各种能源解决方案（尤其是燃料电池和可充电金属-空气电池）的新兴关键。在此，我们报告了镍-铝双层氢氧化物 (NiAl-LDH) 纳米片在碳纳米管 (CNT) 网络上的新型体系。通过金纳米粒子的辅助来形成这样的配合物体系，以形成双金属活性位，从而创建扩展的 Au/NiO 二相区。选择离子液体电解质的双 (三氟甲基磺酰基) 亚胺 (NTf2) 阴离子来增强 CO/O2 的吸附，并通过增加催化界面的亲电性来促进 Ni(OH)2 向 NiOOH 的电催化氧化。所得中性催化体系在 CO 电氧化方面表现出超高的电催化活性和稳定性，优于商业和其他报道的贵金属催化剂。LDH-Au/CNTs COE 催化剂的周转频率 (TOF) 远高于以前报道的其他类似电催化剂，甚至接近高温下固体-气体化学催化剂的活性。此外，在长期耐久性测试中，在 1000 次电化学循环后，电流密度的微小变化仍然存在。
