Abstract Co substitutions for Fe83.3Si4B8P4Cu0.7 precursors are effective to stabilize the nanoporous structures during dealloying in H2SO4 solutions and improve Redox performances of nanoporous electrodes in alkaline conditions. Heterogeneous nanocrystalline structures of Co-substituted Fe83.3-xCoxSi4B8P4Cu0.7 (x = 0, 4, 10 and 20 at.%) alloys consist of two phases: α-Fe(Co) phases and continuously distributed residual amorphous phases. The nanopores on as-dealloyed Fe-Co-Si-B-P-Cu alloys are smaller in size with higher Co concentrations. This is ascribed to the finer α-Fe(Co) phases distributed in the precursor alloys after nanocrystallization. Nanoporous architectures after dealloying inherit the microstructural characteristics of Fe-Co-Si-B-P-Cu precursor alloys. The short-term and long-term CV curves of nanoporous Redox electrodes in 0.5 M KOH solution demonstrate that Redox reactions have been enhanced by partial substitution of Fe by Co and the best Redox performance can be obtained on as-dealloyed Fe79.3Co4Si4B8P4Cu0.7 alloys because of the highest Redox peak current density of 90 mA cm−2 after 150 CV cycles. However, the stabilities of nanoporous Fe79.3Co4Si4B8P4Cu0.7 electrodes have a predictable decline due to the overgrowth of Fe3O4 octahedra and destruction of the ligaments during long-term Redox cycling. On the other hand, the better Redox stabilities has achieved on as-dealloyed Fe63.3Co20Si4B8P4Cu0.7 alloys with stable oxidation peak current densities of 45–47 mA cm−2 from 950 to 3000 CV cycles, about 2.3 times the nanoporous Co-free Fe83.3Si4B8P4Cu0.7 electrodes. The stabilities are considered to result from the relatively small Fe3O4 octahedra, the stabilization of the amorphous Co3O4 outmost layers and the transformation of amorphous and crystalline Co3O4 phases during long-term Redox cycling. The Co substitution of Fe83.3Si4B8P4Cu0.7 precursor alloys can achieve the high Redox performances and good stabilities of nanoporous electrodes.

中文翻译：

---

具有优异氧化还原性能和高稳定性的相脱合金 Fe83.3-xCoxSi4B8P4Cu0.7（x = 4、10 和 20 at.%）前驱体的纳米多孔电极

摘要 Co 取代 Fe83.3Si4B8P4Cu0.7 前驱体可以有效地在 H2SO4 溶液中脱合金过程中稳定纳米多孔结构，并提高纳米多孔电极在碱性条件下的氧化还原性能。Co 取代的 Fe83.3-xCoxSi4B8P4Cu0.7（x = 0、4、10 和 20 at.%）合金的非均质纳米晶结构由两相组成：α-Fe(Co) 相和连续分布的残余非晶相。脱合金后的 Fe-Co-Si-BP-Cu 合金上的纳米孔尺寸较小，Co 浓度较高。这归因于纳米化后分布在前体合金中的更细的 α-Fe(Co) 相。脱合金后的纳米多孔结构继承了 Fe-Co-Si-BP-Cu 前驱体合金的显微结构特征。纳米多孔氧化还原电极在 0 时的短期和长期 CV 曲线。5 M KOH 溶液表明通过 Co 部分取代 Fe 增强了氧化还原反应，并且在脱合金态的 Fe79.3Co4Si4B8P4Cu0.7 合金上可以获得最佳氧化还原性能，因为最高的氧化还原峰值电流密度为 90 mA cm-2 150 个 CV 循环后。然而，由于 Fe3O4 八面体的过度生长和长期氧化还原循环过程中韧带的破坏，纳米多孔 Fe79.3Co4Si4B8P4Cu0.7 电极的稳定性有可预见的下降。另一方面，脱合金后的 Fe63.3Co20Si4B8P4Cu0.7 合金具有更好的氧化还原稳定性，在 950 到 3000 次 CV 循环中具有 45-47 mA cm-2 的稳定氧化峰值电流密度，大约是纳米多孔无钴的 2.3 倍Fe83.3Si4B8P4Cu0.7 电极。稳定性被认为是由相对较小的 Fe3O4 八面体引起的，在长期氧化还原循环过程中，非晶 Co3O4 外层的稳定性以及非晶和结晶 Co3O4 相的转变。Fe83.3Si4B8P4Cu0.7前驱体合金的Co取代可以获得纳米多孔电极的高氧化还原性能和良好的稳定性。