Tuning d-band electronic structure of Ni-Fe oxyhydroxides via doping engineering boosts seawater oxidation performance  

通过掺杂工程调整Ni-Fe氢氧化物的d带电子结构以提升海水氧化性能

作　　者：Liyuan Xiao Xue Bai Jingyi Han Zhenlu Wang Jingqi Guan 肖丽媛;白雪;韩璟怡;王振旅;管景奇(吉林大学化学学院,物理化学研究所,吉林长春130021)

机构地区：[1]Institute of Physical Chemistry,College of Chemistry,Jilin University,Changchun 130021,Jilin,China

出　　处：《Chinese Journal of Catalysis》2025年第4期340-352,共13页催化学报(英文)

基　　金：吉林省自然科学基金(20220101051JC);国家自然科学基金(22075099).

摘　　要：Seawater electrolysis holds significant importance for advancing clean energy conversion.NiFe-based catalysts exhibit outstanding performance in the oxygen evolution reaction(OER)under alkaline conditions.However,the instability of the Fe active center leads to leakage issues,hindering further development in the field of seawater electrolysis.Here,we adopt an element doping engineering strategy to enhance the OER activity of Ni-Fe oxyhydroxides and greatly stabilize the Fe sites by meticulously optimizing the d-band centers.Among the selected metals(Al,Ce,Co,Cr,Cu,Mn,Sn,Zn and Zr),Mn doping is the most effective as confirmed by both theoretical calculations and experimental verifications.The NiFeMn-OOH/NF formed in situ from the corresponding metal-organic framework requires only 217 mV to achieve a current density of 10 mA·cm^(–2) in alkaline seawater,and exhibits exceptional stability.Theoretical calculations uncover that the Fe sites exhibit better balance of adsorption-desorption kinetics for OER intermediates than Ni sites and Ni-Fe dual-sites,while Mn sites with the polyvalent nature modulate the d-band center closer to Fermi level,facilitate the transfer of electrons across the catalyst surface,thus accelerating the reaction kinetics.This work is of considerable significance for achieving efficient and sustainable seawater electrolysis.在全球能源结构转型的大背景下,海水电解技术作为清洁能源转换的重要途径,受到广泛关注.该技术利用丰富的海水资源,通过电解将水分解为氢气和氧气,为可持续能源供应提供了一条绿色且低成本的途径.其中,析氧反应(OER)作为电解水的半反应之一,其催化效率直接关系到整个电解过程的能效和成本.Ni-Fe基催化剂因其在碱性环境下的优异OER性能,被视为最有潜力替代贵金属催化剂的一种材料.然而,尽管Ni-Fe基催化剂展现出良好的活性,但Fe活性中心的不稳定性导致的浸出问题,制约其在海水电解中的实际应用.如何在保持高活性的同时,提升Fe位点的稳定性,成为当前海水电解技术研究的重要方向.本研究采用元素掺杂与原位自重构工程,制备了9种Ni-Fe-M基氢氧化物(M涵盖Al,Ce,Co,Cr,Cu,Mn,Sn,Zn和Zr),并将其锚定于泡沫镍(NF)上.理论筛选给出的火山曲线图指出Mn掺杂的催化剂显示最低的理论过电位.电化学测试证实了上述理论预期,NiFeMn-OOH/NF在9种催化剂中表现出最优的OER性能.在1 mol·L^(–1) KOH电解液中,该催化剂仅需183 mV过电位即可达到10 mA·cm^(–2)电流密度;在碱性海水中,其过电位也仅为217 mV.NiFeMn-OOH/NF||Pt电解槽在碱性海水中也表现出较好的催化性能(E_(10)=1.49 V)和耐腐蚀性(72 h).电化学阻抗谱与稳定性测试进一步证实,Mn掺杂有效降低了电荷转移电阻,显著抑制了Fe的浸出,并增强了催化剂的抗Cl^(–)腐蚀能力,确保了其高活性与长期稳定性.原位拉曼光谱揭示在OER过程中催化剂发生原位重构,转化为富含氧空位的金属氢氧化物,这些重构产物是提升OER效率的关键催化活性位点.理论计算进一步揭示了Mn掺杂提升性能的深层机制:Fe位点因其对OER中间体吸附-脱附动力学的良好平衡,相较于Ni位点及Ni-Fe双位点,展现出更优的催化性能.而Mn掺杂则进一步优化了催化剂的d带中心位�

关 键 词：Nickel-iron oxyhydroxide Oxygen evolution reaction SELF-RECONFIGURATION Seawater electrolysis d-Band center 

分 类 号：O643.36[理学—物理化学]