Key Laboratory of Superhard Materials and ‡Key Laboratory of Physics and Technology for Advanced Batteries, College of Physics, Jilin University , Changchun 130012, China.
ACS Appl Mater Interfaces. 2016 Oct 12;8(40):26886-26894. doi: 10.1021/acsami.6b09717. Epub 2016 Sep 29.
Low activity and high cost of electrocatalysts are the major challenge for the commercialization of the direct fuel cells (DFCs) and biofuel cells. In this work, we demonstrate the desirable "clean surfaces" effect of Cu nanocrystals in electrocatalysis. By a new reaction route of CuO nanospheres (CuO NSs), Cu nanowires (Cu NWs) with high purity and "clean surfaces" are first obtained under mild conditions. Benefiting from the path directing effects and abundant (100) facets, the as-prepared Cu NWs exhibit a lower overpotential to achieve the methanol electro-oxidation reaction (MOR) than that of analogous Cu nanoparticles (Cu NPs). Moreover, the "clean surfaces" provide more available active sites for the efficient transfer of electrons, enabling the Cu NWs to show their enhanced electrocatalytic activity. In the MOR, forward peak current density for the surface-cleaned Cu NWs is 2839 μA cm, which is ca. 6.45-fold higher than that of the Cu NWs with residual capping molecules on their surface. The "clean surfaces" effect can also be extended to the glucose electro-oxidation reaction (GOR), and the enhancement in specific surface area activity for the Cu NWs is 11.3-fold. This work enhances the electrocatalytic performance of Cu nanocrystals without the need for additional noble metals, which opens up new avenues for utilizing non-noble metals in the DFC or biofuel cell applications.
低活性和高成本的电催化剂是直接燃料电池 (DFC) 和生物燃料电池商业化的主要挑战。在这项工作中，我们展示了铜纳米晶体在电催化中理想的“清洁表面”效应。通过氧化铜纳米球 (CuO NSs) 的新反应途径，在温和条件下首次获得了高纯度和“清洁表面”的铜纳米线 (Cu NWs)。得益于路径引导效应和丰富的 (100) 面，所制备的 Cu NWs 在实现甲醇电氧化反应 (MOR) 时表现出比类似的铜纳米颗粒 (Cu NPs) 更低的过电位。此外，“清洁表面”为电子的有效转移提供了更多可用的活性位点，使 Cu NWs 表现出增强的电催化活性。在 MOR 中，表面清洁的 Cu NWs 的正向峰电流密度为 2839 μA cm，约为表面残留封端分子的 Cu NWs 的 6.45 倍。“清洁表面”效应也可以扩展到葡萄糖电氧化反应 (GOR)，Cu NWs 的比表面积活性增强了 11.3 倍。这项工作在不使用额外贵金属的情况下提高了铜纳米晶体的电催化性能，为 DFC 或生物燃料电池应用中使用非贵金属开辟了新途径。
