Abazari Reza, Amani-Ghadim Ali Reza, Slawin Alexandra M Z, Carpenter-Warren Cameron L, Kirillov Alexander M
Department of Chemistry, Faculty of Science, University of Maragheh, Maragheh 55181-83111, Iran.
Applied Chemistry Research Laboratory, Department of Chemistry, Faculty of Sciences, Azarbaijan Shahid Madani University, Tabriz 53751-71379, Iran.
Inorg Chem. 2022 Jun 27;61(25):9514-9522. doi: 10.1021/acs.inorgchem.2c00542. Epub 2022 Jun 14.
Electrocatalytic generation of oxygen is of great significance for sustainable, clean, and efficient energy production. Multiple electron transfer in oxygen evolution reaction (OER) and its slow kinetics represent a serious hedge for efficient water splitting, requiring the design and development of advanced electrocatalysts with porous structures, high surface areas, abundant electroactive sites, and low overpotentials. These requisites are common for metal-organic frameworks (MOFs) and derived materials that are promising electrocatalysts for OER. The present work reports on the synthesis and full characterization of a heteroleptic 3D MOF, [Zn(μ-odba)(μ-bpdh)]·DMF (Zn-MUM-1), assembled from 4,4'-oxydibenzoic acid and 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene (bpdh). Besides, a series of heterometallic MnZn-MUM-1 frameworks (abbreviated as MnZn-MUM-1, MnZn-MUM-1, and MnZn-MUM-1) was also prepared, characterized, and used for the fabrication of working electrodes based on Ni foam (NF), followed by their exploration in OER. These noble-metal-free and robust electrocatalysts are stable and do not require pyrolysis or calcination while exhibiting better electrocatalytic performance than the parent Zn-MUM-1/NF electrode. The experimental results show that the MnZn-MUM-1/NF electrocatalyst features the best OER activity with a low overpotential (253 mV at 10 mA cm) and Tafel slope (73 mV dec) as well as significant stability after 72 h or 6000 cycles. These excellent results are explained by a synergic effect of two different metals present in the Mn-Zn MOF as well as improved charge and ion transfer, conductivity, and stability characteristics. The present study thus widens the application of heterometallic MOFs as prospective and highly efficient electrocatalysts for OER.
电催化产氧对于可持续、清洁且高效的能源生产具有重要意义。析氧反应（OER）中的多电子转移及其缓慢的动力学是高效水分解的严重障碍，这就需要设计和开发具有多孔结构、高比表面积、丰富的电活性位点以及低过电位的先进电催化剂。这些要求对于金属有机框架（MOF）及其衍生材料来说是共有的，它们是很有前景的OER电催化剂。本工作报道了一种由4,4'-氧化二苯甲酸和2,5-双（4-吡啶基）-3,4-二氮杂-2,4-己二烯（bpdh）组装而成的异金属3D MOF [Zn(μ-odba)(μ-bpdh)]·DMF（Zn-MUM-1）的合成及全面表征。此外，还制备并表征了一系列异金属MnZn-MUM-1框架（简称为MnZn-MUM-1、MnZn-MUM-1和MnZn-MUM-1），并将其用于制备基于泡沫镍（NF）的工作电极，随后对其进行OER性能研究。这些无贵金属且坚固的电催化剂很稳定，无需热解或煅烧，同时表现出比母体Zn-MUM-1/NF电极更好的电催化性能。实验结果表明，MnZn-MUM-1/NF电催化剂具有最佳的OER活性，过电位低（10 mA cm时为253 mV），塔菲尔斜率为73 mV dec，并且在72小时或6000次循环后具有显著的稳定性。Mn-Zn MOF中两种不同金属的协同效应以及电荷和离子转移、导电性和稳定性的改善解释了这些优异的结果。因此，本研究拓宽了异金属MOF作为OER潜在高效电催化剂的应用范围。
