Patil Supriya A, Shrestha Nabeen K, Inamdar Akbar I, Bathula Chinna, Jung Jongwan, Hussain Sajjad, Nazir Ghazanfar, Kaseem Mosab, Im Hyunsik, Kim Hyungsang
Department of Nanotechnology and Advanced Materials Engineering, Sejong University, Seoul 05006, Korea.
Division of Physics and Semiconductor Science, Dongguk University, Seoul 04620, Korea.
Nanomaterials (Basel). 2022 Jun 3;12(11):1916. doi: 10.3390/nano12111916.
Developing efficient electrocatalysts for urea oxidation reaction (UOR) can be a promising alternative strategy to substitute the sluggish oxygen evolution reaction (OER), thereby producing hydrogen at a lower cell-voltage. Herein, we synthesized a binder-free thin film of ultrathin sheets of bimetallic Cu-Fe-based metal-organic frameworks (Cu/Fe-MOFs) on a nickel foam via a drop-casting route. In addition to the scalable route, the drop-casted film-electrode demonstrates the lower UOR potentials of 1.59, 1.58, 1.54, 1.51, 1.43 and 1.37 V vs. RHE to achieve the current densities of 2500, 2000, 1000, 500, 100 and 10 mA cm, respectively. These UOR potentials are relatively lower than that acquired by the pristine Fe-MOF-based film-electrode synthesized via a similar route. For example, at 1.59 V vs. RHE, the Cu/Fe-MOF electrode exhibits a remarkably ultra-high anodic current density of 2500 mA cm, while the pristine Fe-MOF electrode exhibits only 949.10 mA cm. It is worth noting that the Cu/Fe-MOF electrode at this potential exhibits an OER current density of only 725 mA cm, which is far inconsequential as compared to the UOR current densities, implying the profound impact of the bimetallic cores of the MOFs on catalyzing UOR. In addition, the Cu/Fe-MOF electrode also exhibits a long-term electrochemical robustness during UOR.
开发用于尿素氧化反应（UOR）的高效电催化剂可能是替代缓慢的析氧反应（OER）的一种有前景的策略，从而在较低的电池电压下产生氢气。在此，我们通过滴铸法在泡沫镍上合成了一种无粘结剂的双金属铜铁基金属有机框架（Cu/Fe-MOFs）超薄片薄膜。除了可扩展的方法外，滴铸薄膜电极在相对于可逆氢电极（RHE）为1.59、1.58、1.54、1.51、1.43和1.37 V时分别实现了2500、2000、1000、500、100和10 mA cm的电流密度，展现出较低的UOR电位。这些UOR电位相对低于通过类似路线合成的原始铁基金属有机框架薄膜电极所获得的电位。例如，在相对于RHE为1.59 V时，Cu/Fe-MOF电极表现出显著的超高阳极电流密度2500 mA cm，而原始铁基金属有机框架电极仅表现出949.10 mA cm。值得注意的是，在此电位下Cu/Fe-MOF电极的OER电流密度仅为725 mA cm，与UOR电流密度相比微不足道，这意味着金属有机框架的双金属核在催化UOR方面具有深远影响。此外，Cu/Fe-MOF电极在UOR过程中还表现出长期的电化学稳定性。
