An ingenious approach for ZIFs derived N-doped hierarchical porous carbon hybrids with FeCo alloy nanoparticles as efficient bifunctional oxygen electrocatalysts
An ingenious approach for ZIFs derived N-doped hierarchical porous carbon hybrids with FeCo alloy nanoparticles as efficient bifunctional oxygen electrocatalysts
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DOI：
10.1016/j.apsusc.2019.05.014
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发表时间：
2019-09-01
影响因子：
6.7
通讯作者：
Xu, Chunjian
中科院分区：
文献类型：
--
作者：
Li, Guoning;Zheng, Kaitian;Xu, Chunjian
提出了一种巧妙的方法来获得氧还原反应(ORR)和析氧反应(OER)的高效双功能氧电催化剂。通过Fe(II)掺杂的ZIF-8分子筛(FeZIF)和乙酰丙酮钴(Co(AcAc)(3))的杂化，成功地制备了具有高比表面积的纳米管、纳米块和包裹的FeCo合金纳米颗粒构成的层次化多孔结构，极大地促进了传质和电子传递。有趣的是，Co(Acac)(3)在制备过程中起着双重作用，它不仅产生了新的金属物种，而且改善了多孔结构。此外，FeZIF还充当了自我牺牲的模板和铁源。由于独特的孔结构、双金属N活性中心和FeCo合金的共同作用，在850℃碳化得到的催化剂在碱性介质中表现出显著的ORR活性，其正半波电位为0.864 V(与可逆氢电极相比)，在10 mA cm(-2)的电流密度下的低操作电位为1.675 V。整个氧电极的电势差为0.81V，超过了目前报道的许多非贵金属基催化剂，表明它是一种很有前途的双功能氧电催化剂。
An ingenious approach is proposed to achieve exceedingly efficient bifunctional oxygen electrocatalysts of oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Hierarchical porous structure constituted by nanotubes and nanobulks with high specific surface area and encapsulated FeCo alloy nanoparticles is successfully prepared via the hybrid of Fe(II)-doped ZIF-8 (FeZIF) and cobalt (III) acetylacetonate (Co(acac)(3)), which is greatly redound to mass transfer and electron transport. Interestingly, Co(acac)(3) plays dual-roles during preparation process, which not only generates new metal species but improves porous structure. Moreover, FeZIF acts as a self-sacrificing template and iron source. Owing to the coaction of the unique porous structure, bimetal-N active sites and FeCo alloy, the resultant catalyst carbonized at 850 degrees C exhibits a prominent ORR activity with a positive half-wave potential of 0.864 V (vs the reversible hydrogen electrode, RHE), and a low operating potential of 1.675 V at a current density of 10 mA cm(-2) for OER in alkaline media. The potential gap (Delta E) of overall oxygen electrode is 0.81 V, which surpass that of numerous non-noble metal-based catalysts reported to date, indicating a promising bifunctional oxygen electrocatalyst.