Electron-Transfer Kinetics of Np3 + ∕ Np4 + , NpO2 + ∕ NpO2 2 + , V2 + ∕ V3 + , and VO2 + ∕ VO2 + at Carbon Electrodes
Electron-Transfer Kinetics of Np3 + ∕ Np4 + , NpO2 + ∕ NpO2 2 + , V2 + ∕ V3 + , and VO2 + ∕ VO2 + at Carbon Electrodes
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DOI：
10.1149/1.1870794
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发表时间：
2005-04
影响因子：
3.9
通讯作者：
T. Yamamura;N. Watanabe;T. Yano;Y. Shiokawa
中科院分区：
文献类型：
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作者：
T. Yamamura;N. Watanabe;T. Yano;Y. Shiokawa
与钒氧化还原对（V2 + /V3+和VO 2 + /VO + 2）一样，镎具有两个同构的可逆氧化还原对（Np 3 + /Np 4 +和NpO + 2 /NpO 2 + 2），是一种很好的氧化还原液流电池活性材料。首次在四种碳电极上测定了镎电极反应的标准速率常数k 0。Np 3 + /Np 4 +和NpO + 2 /NpO 2 + 2在热解石墨c面[PG（c面）]的k 0值分别为1.9 × 10 - 2和1.5 × 10 - 2cm s - 1，也分别为1.4 × 10 - 2和2.1 × 10 - 2cm s- 1。塑料成型碳（PFC）首次测定了PG（c面）和PFC电极上V2 + /V3+和VO 2 + /VO + 2电极反应的标准速率常数。在PFC电极上测得的k 0值比PG（c平面）电极上的大，V2 + /V3+和VO 2 + /VO + 2的k 0分别为5.3 × 10 - 4和8.5 × 10 - 4cms- 1。镎和钒离子的k 0值之间的差异约有10 - 2的顺序，并讨论了这种差异参考这些氧化还原对的均匀的电子交换速率常数。
Like vanadium redox couples (V 2 + /V 3 + and VO 2 + /VO + 2 ), neptunium is a good candidate for the active materials of a redox-flow battery because it possesses two isostructural and reversible redox couples (Np 3 + /Np 4 + and NpO + 2 /NpO 2 + 2 ). The standard rate constants k 0 of the neptunium electrode reactions were first determined at four types of carbon electrodes. The k 0 values for Np 3 + /Np 4 + and NpO + 2 /NpO 2 + 2 are 1.9 X 10 - 2 and 1.5 X 10 - 2 cm s - 1 , respectively, at the c plane of pyrolytic graphite [PG(c plane)] and also 1.4 × 10 - 2 and 2.1 × 10 - 2 cm s - 1 , respectively, at plastic formed carbon (PFC). The standard rate constants for the V 2 + /V 3 + and VO 2 + /VO + 2 electrode reactions were also first determined at PG(c plane) and PFC electrodes. The determined k 0 values are larger at the PFC electrode, k 0 = 5.3 × 10 - 4 and 8.5 × 10 - 4 cm s - 1 for V 2 + /V 3 + and VO 2 + /VO + 2 , respectively, than at the PG(c plane) electrode. There is about a 10 2 order of difference between the k 0 values of neptunium and vanadium ions, and this difference was discussed in reference to the homogeneous electron-exchange rate constants of these redox couples.