This work reports the fabrication of a bifunctional electrocatalyst capable of the CO₂ reduction reaction (CO₂RR) and the O₂ evolution reaction (OER). The catalyst was fabricated by the electrodeposition of a Cu–Ni alloy onto titanium nitride (TiN) nanoparticles on carbon mesh. The use of TiN on carbon as a solid support greatly enhances both the CO₂ reduction and O₂ evolution catalytic activity of the Cu–Ni particles. By combining both the CO₂RR and OER in a two-electrode device, this bifunctional system exhibited good durability for 24 hours at an overpotential of 670 mV at 2 mA cm⁻². In this configuration, this device produced 19.1% CO and 6.7% formate as products of the CO₂RR. Through cyclic voltammetry studies, it was found that Cu–Ni preferentially deposits on TiN as compared to bare carbon, thus allowing for more Cu–Ni to be uniformly deposited, which significantly enhances catalysis. Current densities normalized to the amount of the Cu–Ni catalyst demonstrate that Cu–Ni on TiN/C is significantly more active per gram of catalyst. X-ray diffraction studies suggest that the Cu (111) and Ni (111) facets contribute to the enhanced catalytic activity.

中文翻译：

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氮化钛负载的Cu-Ni双功能电催化剂可减少CO 2和析氧反应

这项工作报告了能够进行CO ₂还原反应（CO ₂ RR）和O ₂析出反应（OER）的双功能电催化剂的制备。催化剂是通过将Cu-Ni合金电沉积到碳网上的氮化钛（TiN）纳米颗粒上而制成的。在碳上作为固体载体使用TiN可以大大增强Cu-Ni颗粒的CO ₂还原和O ₂析出催化活性。通过将CO ₂ RR和OER结合在一个双电极设备中，该双功能系统在2 mA cm ^-2的670 mV过电势下显示了24小时的良好耐久性。在此配置中，此设备以CO ₂ RR的产品形式生成了19.1％的CO和6.7％的甲酸。通过循环伏安法研究，发现与裸碳相比，Cu-Ni优先沉积在TiN上，因此可以使更多的Cu-Ni均匀沉积，从而大大增强了催化作用。电流密度归一化为Cu-Ni催化剂的量表明，TiN / C上的Cu-Ni每克催化剂活性更高。X射线衍射研究表明，Cu（111）和Ni（111）面有助于增强催化活性。