有机框架结构对NiFe-MOF析氧反应的影响  

Effect of organic framework structure on NiFe-MOF for oxygen evolution reaction

作　　者：钟达忠 赵陶 郝根彦 赵强[1,2] ZHONG Dazhong;ZHAO Tao;HAO Genyan;ZHAO Qiang(College of Chemistry and Chemical Engineering,Taiyuan University of Technology,030024 Taiyuan,China;Shanxi Key Laboratory of Gas Energy Efficient and Clean Utilization,030024 Taiyuan,China;Shanxi College of Technology,036000 Shuozhou,China)

机构地区：[1]太原理工大学化学工程与技术学院,太原030024 [2]山西省气体能源高效清洁利用重点实验室,太原030024 [3]山西工学院,山西朔州036000

出　　处：《煤炭转化》2024年第4期114-124,共11页Coal Conversion

基　　金：国家自然科学基金项目(22308246,21975175,21878202);中央引导地方科技发展资金项目(YDZJSX20231A015);山西省基础研究计划项目(202203021212266)。

摘　　要：合理设计用于电解水制氢阳极析氧反应(OER)的高活性电催化剂对清洁能源和生态可持续发展至关重要。然而,由于OER四电子转移的动力学过程较为缓慢,导致过电位较高,开发高效的阳极催化剂仍是一个重大挑战。金属有机框架(MOF)因结构多样性和超高的比表面积被视为有潜力的OER电催化剂。NiFe双金属材料具有优异的阳极析氧催化活性,但针对MOF材料活性的调控主要集中在金属中心的设计上,而阴离子有机配体对阳极析氧催化活性的影响依然未知。因此,采用溶剂热法构建具有等网状结构的系列羧酸型NiFe-MOF来阐明羧酸连接体不同长度对OER性能的影响(三种不同的有机配体分别为:对苯二甲酸(BDC)、2,6-萘二甲酸(NDC)和4,4′-联苯二甲酸(BPDC))。通过X射线衍射、拉曼光谱、红外光谱、扫描电子显微镜和X射线光电子能谱,分析了催化剂的性质、微观形貌和电荷结构,并在1 mol/L KOH溶液中进行了电化学测试。结果表明:NiFe-BDC在10 mA/cm^(2)的电流密度处过电位仅为223 mV,远低于NiFe-NDC和NiFe-BPDC的过电位,二者此处的过电位分别为267 mV和284 mV;此外,NiFe-BDC在长时间测试中表现了出色的稳定性(200 h),其优异的性能主要归因于有机配体在催化中起到优化电荷结构的作用,并且展现出丰富的活性中心,共同促进了OER电催化性能。The rational design of highly active electrocatalysts for oxygen evolution reactions(OER) is essential for the sustainable development of clean energy and the environment.However,due to the slow kinetic process of OER with four electrons transfer,it requires a high overpotential,making the development of efficient anode catalysts a significant challenge.Metal-organic frameworks(MOF) are considered potential OER electrocatalysts due to their structural diversity and high specific surface area.Currently,NiFe bimetal materials have been found to exhibit excellent catalytic activity of OER.While the modulation of the activity for MOF materials mainly focuses on the design of the metal centers,and the influence of anionic organic framework on OER performance is still unclear.Therefore,aseries of carboxylate-type bimetal NiFe-MOFs with isoreticular structures were constructed using a solvothermal method to elucidate the effect of different carboxylate-type ligand lengths on their OER performance.The three different carboxylate-type ligands were:terephthalic acid(BDC),naphthalene-2,6-dicarboxylicacid(NDC),and biphenyl-4,4′-dicarboxylic acid(BPDC).The properties,morphology and charge structure of the catalysts were analyzed by using X-ray diffraction(XRD),Raman spectroscopy,infrared spectroscopy(FTIR),scanning electron microscopy(SEM),and X-ray photoelectron spectroscopy(XPS),followed by electrochemical testing in 1 mol/L KOH solution.The results show that NiFe-BDC only requires an overpotential of 223 mV at a current density of 10 mA/cm^(2) in 1 mol/L KOH,which is much lower than that of NiFe-NDC(267mV) and NiFe-BPDC(284 mV).In addition,NiFe-BDC demonstrates excellent activity and stability for up to 200 h.The excellent performance is mainly attributed to role of organic ligands in optimizing the charge structures during the catalytic process and exhibiting abundant active centers,which collectively enhance the electrocatalytic performance of OER.

关 键 词：金属有机框架 析氧反应 结构设计 配体调控 电催化剂 稳定性 

分 类 号：TQ116.2[化学工程—无机化工] TQ426