质子交换膜燃料电池
催化作用
一氧化碳
氢氧化物
近程
氢
化学
纳米颗粒
过氧化氢
氢燃料
氧化物
化学工程
材料科学
无机化学
纳米技术
有机化学
工程类
作者
Lina Cao,Wei Liu,Qiquan Luo,Ruoting Yin,Bing Wang,Jonas Weissenrieder,Markus Soldemo,Huan Yan,Yue Lin,Zhihu Sun,Chao Ma,Wenhua Zhang,Si Chen,Hengwei Wang,Qiaoqiao Guan,Takeshi Yao,Shiqiang Wei,Jinlong Yang,Junling Lu
出处
期刊:Nature
[Springer Nature]
日期:2019-01-01
卷期号:565 (7741): 631-635
被引量:427
标识
DOI:10.1038/s41586-018-0869-5
摘要
Proton-exchange-membrane fuel cells (PEMFCs) are attractive next-generation power sources for use in vehicles and other applications1, with development efforts focusing on improving the catalyst system of the fuel cell. One problem is catalyst poisoning by impurity gases such as carbon monoxide (CO), which typically comprises about one per cent of hydrogen fuel2-4. A possible solution is on-board hydrogen purification, which involves preferential oxidation of CO in hydrogen (PROX)3-7. However, this approach is challenging8-15 because the catalyst needs to be active and selective towards CO oxidation over a broad range of low temperatures so that CO is efficiently removed (to below 50 parts per million) during continuous PEMFC operation (at about 353 kelvin) and, in the case of automotive fuel cells, during frequent cold-start periods. Here we show that atomically dispersed iron hydroxide, selectively deposited on silica-supported platinum (Pt) nanoparticles, enables complete and 100 per cent selective CO removal through the PROX reaction over the broad temperature range of 198 to 380 kelvin. We find that the mass-specific activity of this system is about 30 times higher than that of more conventional catalysts consisting of Pt on iron oxide supports. In situ X-ray absorption fine-structure measurements reveal that most of the iron hydroxide exists as Fe1(OH)x clusters anchored on the Pt nanoparticles, with density functional theory calculations indicating that Fe1(OH)x-Pt single interfacial sites can readily react with CO and facilitate oxygen activation. These findings suggest that in addition to strategies that target oxide-supported precious-metal nanoparticles or isolated metal atoms, the deposition of isolated transition-metal complexes offers new ways of designing highly active metal catalysts.
科研通智能强力驱动
Strongly Powered by AbleSci AI