Sr3Mn2O6 and Sr3FeMnO6 for oxygen and hydrogen evolution electrocatalysis
Sr3Mn2O6 and Sr3FeMnO6 for oxygen and hydrogen evolution electrocatalysis
复制标题
DOI：
10.1007/s10008-022-05167-1
复制
发表时间：
2022-04
影响因子：
2.5
通讯作者：
S. Karki;Ram Krishna Hona;F. Ramezanipour
中科院分区：
文献类型：
--
作者：
S. Karki;Ram Krishna Hona;F. Ramezanipour
合成了准二维氧化物Sr_3Mn_2O_6和Sr_3FeMnO_6，研究了它们对水裂解的两个半反应，析氧反应（OER）和析氢反应（HER）。这两种材料是同构的，由（Fe/Mn）O 5四方锥单元组成，形成二维层，由锶离子隔开。这种结构类型与所谓的Ruddlesden-Popper（RP）结构有关，其通常每个化学式单元含有7个氧，并且由八面体配位的过渡金属组成。在这项工作中的两种材料可以被描述为缺氧RP系统。这两种化合物显示出OER和HER的电催化活性，Sr 3FeMnO 6具有显着更大的性能相比，Sr 3 Mn 2 O 6。对于Sr 3FeMnO 6，OER和HER两者所需的过电位显著降低。与Sr 3 Mn 2 O 6相比，该材料还显示出更快的反应动力学和更大的电化学活性表面积。虽然Sr 3FeMnO 6的活性没有达到最先进的催化剂，其双功能电催化性能是显着的。此外，它还展示了电负性在指导电催化等功能特性方面的重要作用。图形摘要
Quasi-two-dimensional oxides Sr3Mn2O6and Sr3FeMnO6have been synthesized and their bifunctional electrocatalytic activity toward both half-reactions of water-splitting, i.e., oxygen-evolution reaction (OER) and hydrogen-evolution reaction (HER), has been demonstrated. The two materials are isostructural and consist of (Fe/Mn)O5square-pyramidal units that form two-dimensional layers, separated by strontium ions. This structure type is related to the so-called Ruddlesden-Popper (RP) structure, which typically contains 7 oxygens per formula unit and consists of octahedrally coordinated transition metals. The two materials in this work can be described as oxygen-deficient RP systems. Both compounds show electrocatalytic activity for OER and HER, with Sr3FeMnO6having a significantly greater performance compared to Sr3Mn2O6. The overpotential required for both OER and HER is considerably lowered for Sr3FeMnO6. This material also shows faster reaction kinetics and greater electrochemically active surface area compared to Sr3Mn2O6. While the activity of Sr3FeMnO6does not reach those of state-of-the-art catalysts, its bifunctional electrocatalytic performance is remarkable. In addition, it demonstrates the important role of electronegativity in directing functional properties such as electrocatalysis.Graphical abstract