The effect of Fe as constituent in Ni-base alloys on the oxygen evolution reaction in alkaline solutions at high current densities
The effect of Fe as constituent in Ni-base alloys on the oxygen evolution reaction in alkaline solutions at high current densities
复制标题
DOI：
10.1016/j.ijhydene.2019.01.182
复制
发表时间：
2019-03
影响因子：
7.2
通讯作者：
T. Rauscher;C. I. Bernäcker;U. Mühle;B. Kieback;L. Röntzsch
中科院分区：
文献类型：
--
作者：
T. Rauscher;C. I. Bernäcker;U. Mühle;B. Kieback;L. Röntzsch
研究了纳米镍基合金在碱性水电解工业操作条件下的析氧反应(OER)催化剂。通过快速凝固和随后的高能球磨制备了不同的合金。在OER活性方面，298K时，纳米晶NiSingle键Fe合金在29.9wt.-%KOH中获得了最好的OER活性，而在高温(333K)下，纳米晶NiSingle键Fe和Ni合金以及多晶Ni的OER活性与之相当。这一最初难以理解的结果可以通过在试剂级KOH溶液中以杂质形式存在的铁进入NiOOH阳极表面层来解释。然而，经过长期的运行，纳米晶NiSingle结合铁合金表现出了明显的更好的活性，特别是在电流密度高达1A/cm−2时。结果表明，纳米晶NiSingle结合铁合金在不同负载下运行95h后，表现出非常高的效率和良好的长期活性(0.3A/cm−2时375V过电位)。
Nanocrystalline Nickel-based alloys were investigated as catalysts for the oxygen evolution reaction (OER) at industrial operation conditions for alkaline water electrolysis. Different alloys were prepared by rapid solidification and subsequent high-energy milling. Regarding OER activity, the best efficiency was obtained for a nanocrystalline Nisingle bondFe alloy in 29.9 wt.-% KOH at 298 K. However, at elevated temperature (333 K), comparable activities were determined in short-term experiments for nanocrystalline Nisingle bondFe and Ni alloys as well as for polycrystalline Ni. This initially incomprehensible outcome can be explained by the incorporation of Fe, which is present as impurity in the reagent grade KOH solution, into the NiOOH anode surface layer. However, after a long-term operation, the nanocrystalline Nisingle bondFe alloy shows a significantly better activity, in particular, at altering current density of up to 1 A cm−2. As a result, the nanocrystalline Nisingle bondFe alloy exhibits a very high efficiency and excellent long-term activity (375 mV overpotential at 0.3 A cm−2) after 95 h of operation at different loads.