Manganese oxides have received much attention over the years among the wide range of electrocatalysts for the oxygen evolution reaction (OER) due to their low toxicity, high abundance and rich redox chemistry. While many previous studies focused on the activity of these materials, a better understanding of the material transformations relating to activation or degradation is highly desirable, both from a scientific perspective and for applications. We electrodeposited Na-containing MnO x without long-range order from an alkaline solution to investigate these aspects by cyclic voltammetry, scanning electron microscopy and x-ray absorption spectroscopy at the Mn-K and Mn-L edges. The pristine film was assigned to a layered edge-sharing Mn 3+/4+ oxide with Mn-O bond lengths of mainly 1.87 Å and some at 2.30 Å as well as Mn-Mn bond lengths of 2.87 Å based on fits to the extended x-ray fine structure. The decrease of the currents at voltages before the onset of th...

中文翻译：

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电沉积锰氧化物作为氧释放反应催化剂的循环伏安法过程中的可逆和不可逆过程

多年来，由于氧化锰的低毒性，高丰度和丰富的氧化还原化学作用，在众多用于氧释放反应（OER）的电催化剂中受到了广泛的关注。尽管先前的许多研究都集中在这些材料的活性上，但无论是从科学角度还是从应用角度来看，都非常需要对与活化或降解有关的材料转变有更好的了解。我们从碱性溶液中无长距离电沉积含钠的MnO x，以通过循环伏安法，扫描电子显微镜和x射线吸收光谱法在Mn-K和Mn-L边缘研究这些方面。将原始膜分配给层状边缘共享的Mn 3 + / 4 +氧化物，其Mn-O键长主要为1.87Å，有些为2.30Å，而Mn-Mn键长为2。基于适合扩展X射线精细结构的87Å。电流开始前的电压下电流的减小