Sankar Selvasundarasekar Sam, Keerthana Govindaraj, Manjula Karthikeyan, Sharad Jeyashankararaj Hirithya, Kundu Subrata
Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
Electrochemical Process Engineering (EPE) Division, CSIR-Central Electrochemical Research Institute (CECRI), Karaikudi 630003, Tamil Nadu, India.
Inorg Chem. 2021 Mar 15;60(6):4034-4046. doi: 10.1021/acs.inorgchem.1c00097. Epub 2021 Mar 1.
The explorations of earth-abundant, noble metal-free, highly efficient electrocatalysts for water-splitting reactions have been considered as highly significant for imperishable energy production. Though the metal organic framework (MOF)-based materials are highly promising candidates in the area of material chemistry, the combined properties associated with MOFs and the one-dimensional (1D) fibrous matrix, which can lead to better electrocatalytic performance, have been less explored. Herein, we ascertain a fabrication method for ZIF-67 (zeolite imidazolate framework) nanofibers (NFs), Fe-ZIF NFs, and Fe-ZIF-67 NFs via the wet chemical combined electrospinning (ES) approach. The as-synthesized catalysts were utilized for the electrochemical reaction, which showed a high efficiency toward the oxygen evolution reaction (OER). Compared to other catalysts, the Fe-ZIF-67 NF catalyst showed a very less overpotential of 278 mV at a fixed current density of 10 mA cm. The obtained Tafel slope and values are 77 mV dec and 1.2 Ω, respectively. The post-X-ray photoelectron spectroscopy (XPS) analysis revealed the transformation of FeOOH during the OER study along with Co states in mixed Fe-ZIF-67 NFs. In an alkaline electrolyzer, Fe-ZIF-67 NFs were utilized as the anode and a Pt wire as the cathode in 1 M KOH solution, which required a cell voltage of 1.68 V at 10 mA cm current density with astonishing stability. Hence, this work should open a new path for the exploration of efficient non-noble metal catalysts for energy-related applications.
探索用于水分解反应的储量丰富、不含贵金属的高效电催化剂，对于可持续能源生产具有重要意义。尽管基于金属有机框架（MOF）的材料在材料化学领域是非常有前景的候选材料，但与MOF和一维（1D）纤维基质相关的综合性能，可能会带来更好的电催化性能，这方面的研究还较少。在此，我们通过湿化学结合静电纺丝（ES）方法确定了一种制备ZIF-67（沸石咪唑酯框架）纳米纤维（NFs）、Fe-ZIF NFs和Fe-ZIF-67 NFs的方法。合成的催化剂用于电化学反应，对析氧反应（OER）表现出高效率。与其他催化剂相比，Fe-ZIF-67 NF催化剂在固定电流密度为10 mA cm时，过电位非常低，仅为2７8 mV。获得的塔菲尔斜率和电阻值分别为77 mV dec和1.2 Ω。X射线光电子能谱（XPS）分析表明，在OER研究过程中，FeOOH发生了转变，同时混合Fe-ZIF-67 NFs中存在Co状态。在碱性电解槽中，Fe-ZIF-67 NFs在1 M KOH溶液中用作阳极，铂丝用作阴极，在10 mA cm电流密度下，电池电压为1.68 V，稳定性惊人。因此，这项工作应为探索用于能源相关应用的高效非贵金属催化剂开辟一条新途径。
