A novel self-assembly approach for synthesizing nanofiber aerogel supported platinum single atoms
Autor: | Miho Yamauchi, Yonghui Zhao, Haojie Zhang, Xiaopeng Li, Zheng Jiang, Ruoou Yang, Yu Sun, Chao Lin, Kenichi Kato, Qing Xu, Hao Zhang |
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Rok vydání: | 2020 |
Předmět: |
Materials science
Renewable Energy Sustainability and the Environment Nanowire chemistry.chemical_element Aerogel 02 engineering and technology General Chemistry Manganese 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Catalysis chemistry Chemical engineering Nanofiber General Materials Science Self-assembly 0210 nano-technology Platinum Nanoscopic scale |
Zdroj: | Journal of Materials Chemistry A. 8:15094-15102 |
ISSN: | 2050-7496 2050-7488 |
Popis: | A great challenge in catalyst engineering is precisely assembling and positioning nanoscale active metals at desired locations while constructing robust functional architectures. This article presents a novel approach for constructing macroscopic Ag-doped manganese oxide aerogels (up to 2 L) while homogeneously incorporating active Pt single atoms (Pt/Ag-MnO2) based on a solution–solid–solid (SSS) mechanism. AgOx seeds were identified as key species for triggering the octopus-like growth of MnO2 nanofibers and inserting Ag and Pt into the MnO2 crystalline framework. The interconnection and entanglement among nanofibers allowed the formation of mechanically strengthened hierarchical structures, leading to one of the most robust manganese-based aerogels to date. Impressively, the Pt/Ag-MnO2 aerogel also possessed promising selectivity and stability toward the electrocatalytic oxygen reduction reaction, with Pt showing a high mass activity of 1.6 A/(mgPt) at 0.9 V vs. RHE. Experimental characterization and theoretical calculation confirmed Pt single atoms to be located at substitutional lattice sites, which reduced the overall oxygen reduction barriers. Our approach suggests that SSS or other analogous nanofiber or nanowire growth strategies are powerful in controlling structural formation over the entire range of length scales while being applicable to fabricating single-atom catalysts. |
Databáze: | OpenAIRE |
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