摘要
锌-空气电池作为一种兼具成本低、容量高、环境友好等优点的高效储能器件,具有1084 Wh/kg的理论能量密度,甚至高于传统锂离子电池.锌-空气电池主要受限于其空气电极材料氧还原(ORR)和析氧反应(OER)缓慢的动力学,因此大量的研究都集中在如何优化其催化活性上.目前应用最广泛的ORR和OER的催化剂分别是Pt/C和RuO2,但是其高昂的价格和稀缺性使其应用受限.金属有机框架(MOF)是金属阳离子或阳离子团簇与有机配体配位形成的配位聚合物,具有高比表面积与结构可调控性等优势,经高温煅烧后可以获得结构各异且异原子掺杂(例如氮掺杂)的碳化物材料,展现了优良的ORR和OER催化活性,成为电催化领域的研究热点.类普鲁士蓝是一种典型的MOF材料,具有成分易调控、合成方法简单等优点.本研究通过氢氧化钴纳米棒的原位转化制备负载在泡沫镍上的钴铁双金属类普鲁士蓝,并以此为前驱体制备了氮掺杂钴铁双金属碳化物催化剂;使用扫描电子显微镜(SEM)、X光衍射(XRD)、X光电子能谱(XPS)等手段对样品进行表征;使用旋转圆盘电极、线扫描等测试材料研究其对ORR和OER催化性能的影响.结果表明,所制备的氮掺杂钴铁双金属碳化物催化剂具备较好的ORR和OER活性.在0.1 mol/L KOH溶液中,ORR半波电位为0.81 V;1.0 mol/L KOH中,OER电流密度达到10 mA/cm^2时,过电位为300 mV.该材料作为空气电极催化剂组装锌-空气电池,开路电压为1.29 V,且具备较好的稳定性和循环性.
Zinc-air battery is a high-efficient energy storage system with many advantages such as low-cost,high capacity and environmental-friendly.Theoretically,zinc-air battery has an energy density of about 1084 Wh/kg,which is much higher than that of traditional lithium ion battery.The performance of zinc-air battery is limited by sluggish reaction kinetics of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)of air electrode,which requires the intense explore for the both activities.The well-known catalyst for ORR and OER is Pt/C and RuO2 individually,which are hindered by their high cost and scarcity.Recently,nitrogen doped metal carbide catalyst has emerged as a promising candidate for replacing Pt/C.Usually,the OER activity of nitrogen doped metal carbide structure is not as good as that of ORR,and the traditional bulk structure of catalyst on substrate electrode hinders the gas diffusion process,which can easily accumulated bubbles on the air electrode,and may lead to leakage of electrolyte solution.So hierarchical nitrogen doped metal carbide structure material is needed to accelerate the diffusion of both O2 and electrolyte.Metal organic framework(MOF)is a kind of organic polymer generated by coordination between metal ions and organic ligand.So far,researchers have obtained MOF with various topological structures by using different metal ions and ligands to assemble it.MOF with ligands containing nitrogen can be converted to nitrogen doped metal carbide structure using annealing method under specific conditions.Moreover,the net-like structure of MOF contributes to a defect-rich and porous carbon structure of the product,which is essential to promote catalytic activity,and makes MOF ideal precursor for synthesizing nitrogen doped metal carbide catalyst.Prussian blue analogue(PBA)used in this research is a typical kind of MOF.PBA is generated by coordination between transition metal ions(Fe3+and Co2+)and cyanide ion.With a simple cubic crystal structure,PBA is the first discovered MOFs,and has a his
作者
施可飞
杨皓景
连跃彬
彭扬
Kefei Shi;Haojing Yang;Yuebin Lian;Yang Peng(Soochow Institute of Energy and Material Innovations,College of Energy,Soochow University,Suzhou 215006,China;Provincial Key Laboratory for Advanced Carbon Materials and Wearable Energy Technologies,Soochow University,Suzhou 215006,China)
出处
《科学通报》
EI
CAS
CSCD
北大核心
2019年第32期3378-3384,共7页
Chinese Science Bulletin
基金
国家自然科学基金(21701118)
江苏省高等学校自然科学研究重大项目(18KJA480004)
江苏省优势学科资助
关键词
类普鲁士蓝
氮掺杂金属碳化物
氧还原反应
析氧反应
锌-空气电池
Prussian blue analogue
nitrogen doped metal carbide
oxygen reduction reaction
oxygen evolution reaction
Znair battery
