3D porous graphitic nanocarbon for enhancing the performance and durability of Pt catalysts: a balance between graphitization and hierarchical porosity
| Autor: | Yanghua He, Zhenxing Feng, Zhi Qiao, Mengjie Chen, Jacob S. Spendelow, Maoyu Wang, Widitha Samarakoon, Guofeng Wang, Chenyu Wang, Dong Su, Dongguo Li, Sooyeon Hwang, Hua Zhou, Stavros Karakalos, Zhenyu Liu, Xing Li, Gang Wu |
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| Rok vydání: | 2019 |
| Předmět: |
chemistry.chemical_classification
Materials science Renewable Energy Sustainability and the Environment Carbonization Proton exchange membrane fuel cell chemistry.chemical_element 02 engineering and technology Polymer 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Pollution 0104 chemical sciences Corrosion Catalysis Nuclear Energy and Engineering chemistry Chemical engineering Environmental Chemistry 0210 nano-technology Porosity Pyrolysis Carbon |
| Zdroj: | Energy & Environmental Science. 12:2830-2841 |
| ISSN: | 1754-5706 1754-5692 |
| DOI: | 10.1039/c9ee01899a |
| Popis: | Carbon supports used in oxygen-reduction cathode catalysts for proton exchange membrane fuel cells (PEMFCs) are vulnerable to corrosion under harsh operating conditions, leading to poor performance durability. To address this issue, we have developed highly stable porous graphitic carbon (PGC) produced through pyrolysis of a 3D polymer hydrogel in combination with Mn. The resulting PGC features multilayer carbon sheets assembled in porous and flower-like morphologies. In situ high-temperature electron microscopy was employed to dynamically monitor the carbonization process up to 1100 °C, suggesting that the 3D polymer hydrogel provides high porosity at multiple scales, and that Mn catalyzes the graphitization process more effectively than other metals. Compared to conventional carbon supports such as Vulcan, Ketjenblack, and graphitized carbon, PGC provides an improved balance between high graphitization and hierarchical porosity, which is favorable for uniform Pt nanoparticle dispersion and enhanced corrosion resistance. As a result, Pt supported on PGC exhibits remarkably enhanced stability. In addition to thorough testing in aqueous electrolytes, we also conducted fuel cell testing using durability protocols recommended by the U.S. Department of Energy (DOE). After 5000 voltage cycles from 1.0 to 1.5 V, the Pt/PGC catalyst only lost 9 mV at a current density of 1.5 A cm−2, dramatically exceeding the DOE support durability target ( |
| Databáze: | OpenAIRE |
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