Murtaza Maida, Farooq Komal, Shah Waqas Ali, Ahmad Iftikhar, Waseem Amir
Department of Chemistry, Quaid-i-Azam University Islamabad Pakistan
School of Chemistry and Chemical Engineering, Henan Normal University Xinxiang 453007 China.
Nanoscale Adv. 2024 Oct 21;6(24):6317-27. doi: 10.1039/d4na00630e.
Metal organic frameworks (MOFs) have a porous structure, high surface area, and high charge transfer, and they have been regarded as model electrocatalysts. Optimization of the electrocatalytic activity of MOFs is challenging, and an effective strategy for this optimization is the construction of a well-defined interfacial bond bridge. In this work, an approach of composite synthesis is reported for MOF (CoNiNHBDC) with MXenes (MoTiC), as the electrocatalytic properties of MOF can be greatly enhanced with the incorporation of the conductive material MXene. The prepared composite material was characterized thoroughly using XRD, XPS, FESEM, EDX, TEM, and BET. The synergistic effect of both components of this composite material resulted in enhanced conductivity and the number of active sites, which led to enhanced electrocatalytic performance. The CoNiNHBDC MOF with different ratios of MoTiC MXene were synthesized, and the resulting materials were evaluated for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) activities. It was observed that the MOFMX3 attained a 10 mA cm current density at 1.44 V for OER and -0.037 V for HER ( RHE), and lower values of Tafel slopes of 44.8 mV dec for OER and 45 mV dec for HER in 0.1 M KOH were achieved. The higher double layer capacitance ( ) values lead to high electrochemical surface area (ECSA) values. Lower Tafel slope values for MOFMX3 show that the presence of MXene nanosheets in the hybrid provides support to the layered and porous configuration of MOF, and the chances of the interaction of electrolyte to the catalytically active sites are significantly enhanced. This work highlights the idea of growing bimetallic MOFs on MoTiC MXene using an interdiffusion reaction strategy and opens up an avenue for designing highly electrocatalytic systems.
金属有机框架材料(MOFs)具有多孔结构、高比表面积和高电荷转移能力,被视为典型的电催化剂。优化MOFs的电催化活性具有挑战性,而实现这种优化的有效策略是构建明确的界面键桥。在这项工作中,报道了一种将MOF(CoNiNHBDC)与MXenes(MoTiC)进行复合合成的方法,因为MOF与导电材料MXene结合后其电催化性能可得到极大增强。使用XRD、XPS、FESEM、EDX、TEM和BET对制备的复合材料进行了全面表征。这种复合材料两种组分的协同效应提高了导电性和活性位点数量,从而提升了电催化性能。合成了具有不同MoTiC MXene比例的CoNiNHBDC MOF,并对所得材料的析氧反应(OER)和析氢反应(HER)活性进行了评估。结果发现,MOFMX3在1.44 V时达到10 mA cm的OER电流密度,在 -0.037 V时达到HER(相对于可逆氢电极)电流密度,并且在0.1 M KOH中OER的塔菲尔斜率为44.8 mV dec⁻¹,HER的塔菲尔斜率为45 mV dec⁻¹。较高的双层电容值导致较高的电化学表面积(ECSA)值。MOFMX3较低的塔菲尔斜率值表明,杂化材料中MXene纳米片的存在为MOF的层状和多孔结构提供了支撑,显著增加了电解质与催化活性位点相互作用的机会。这项工作突出了利用互扩散反应策略在MoTiC MXene上生长双金属MOFs的理念,并为设计高电催化系统开辟了一条途径。