NbOx nano-nail with a Pt head embedded in carbon as a highly active and durable oxygen reduction catalyst
NbOx nano-nail with a Pt head embedded in carbon as a highly active and durable oxygen reduction catalyst
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DOI：
10.1016/j.nanoen.2020.104455
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发表时间：
2020-03-01
期刊：
影响因子：
17.6
通讯作者：
Chen, Zhongwei
中科院分区：
文献类型：
--
作者：
Ma, Zhong;Li, Shuang;Chen, Zhongwei
燃料电池的汽车应用需要进一步提高铂基氧还原催化剂的活性和耐久性。然而，这是一项非常具有挑战性的任务。在这里，我们描述了一种新的方法，利用碳表面的孔洞在高温下固定低氧化态的NbOx纳米颗粒，而不过度生长，然后选择性地在NbOx上沉积铂磁头，这是由于它们之间的氧化还原作用产生的。这种新型结构的催化剂，在0.6~1.0V和1~1.5V之间分别循环50,000次和5,000次后，其质量活性均大于0.5A mg(-1)，分别是铂/C催化剂上0.07和0.13A mg(-1)的7倍和4倍。高可持续的ORR活性归因于强大的金属-载体相互作用，最大限度地提高了铂的利用率，减少了颗粒团聚、碳腐蚀和金属氧化。此外，将纳米颗粒嵌入到碳孔中的方法很可能被用于开发各种应用的均匀分散的小颗粒。
Further enhancing activity and durability of Pt-based catalysts for oxygen reduction is needed for the automotive application of fuel cells. This is however a very challenging task. Herein, we describe a new method to nail down low-oxidation-state NbOx nanoparticles at high temperature without overgrowth using the surface pores on carbon and then deposit Pt head selectively on top of NbOx derived by the redox reduction between themselves. This new structured catalyst, Pt-NbOxC, exhibited mass activities higher than 0.5 A mg(-1) after 50,000 cycles between 0.6 and 1.0 V and 5,000 cycles between 1 and 1.5 V, which are 7 and 4 times of the 0.07 and 0.13 A mg(-1), respectively, on Pt/C. That high sustainable ORR activity is ascribed to strong metal-support interaction that maximizes Pt utilization and minimizes particle agglomeration, carbon corrosion and metal oxidation. Furthermore, the method embedded nanoparticles into carbon pores will likely be used in developing small particles with uniform dispersion for various applications.