Tesfaye Robel Mehari, Das Gautam, Park Bang Ju, Kim Jihyeon, Yoon Hyon Hee
Department of Chemical and Biological Engineering, Gachon University, Seongnam, Gyeonggi-do, 13120, Republic of Korea.
Department of Electronic Engineering, Gachon University, Seongnam, Gyeonggi-do, 13120, Republic of Korea.
Sci Rep. 2019 Jan 24;9(1):479. doi: 10.1038/s41598-018-37011-w.
Ni-based catalysts have been considered as an efficient anode material for urea fuel cells due to the low cost and high activity in alkaline media. Herein, we demonstrate that Ni-Co bimetallic nanoparticles decorated carbon nanotube aerogels as catalysts for urea oxidation reaction (UOR) can be synthesized by a polyol reduction and sol-gel method. The morphology, structure, and composition of the Ni-Co/MWCNT aerogels were characterized by scanning electron microscopy and X-Ray diffraction. The electro-catalytic activity of the Ni-Co/MWCNT aerogels towards UOR was investigated using cyclic voltammetry. It was found that the Co-doping at 25% (Co/Ni) significantly increased the oxidation peak current and reduced the overpotential of the UOR. Furthermore, the MWCNT aerogel support also remarkably enhanced electro-catalytic activity by providing a high surface area and fast mass transport for the UOR owing to the porous 3D network structures with uniform distribution of Ni-Co nanoparticles. Urea/O fuel cell with Ni-Co/MWCNT aerogel as anode material exhibited an excellent performance with maximum power density of 17.5 mWcm with an open circuit voltage of 0.9 V. Thus, this work showed that the highly porous three-dimensional Ni-Co/MWCNT aerogel catalysts can be used for urea oxidation and as an efficient anode material for urea fuel cells.
由于成本低且在碱性介质中具有高活性，镍基催化剂被认为是尿素燃料电池的一种高效阳极材料。在此，我们证明了通过多元醇还原和溶胶-凝胶法可以合成装饰有碳纳米管气凝胶的镍钴双金属纳米颗粒作为尿素氧化反应（UOR）的催化剂。通过扫描电子显微镜和X射线衍射对镍钴/多壁碳纳米管气凝胶的形态、结构和组成进行了表征。使用循环伏安法研究了镍钴/多壁碳纳米管气凝胶对UOR的电催化活性。发现25%（钴/镍）的钴掺杂显著增加了氧化峰电流并降低了UOR的过电位。此外，多壁碳纳米管气凝胶载体由于具有镍钴纳米颗粒均匀分布的多孔三维网络结构，通过为UOR提供高表面积和快速质量传输，也显著增强了电催化活性。以镍钴/多壁碳纳米管气凝胶作为阳极材料的尿素/O燃料电池表现出优异的性能，最大功率密度为17.5 mW/cm²，开路电压为0.9 V。因此，这项工作表明，高度多孔的三维镍钴/多壁碳纳米管气凝胶催化剂可用于尿素氧化，并作为尿素燃料电池的高效阳极材料。
