NOx Storage Performance at Low Temperature over Platinum Group Metal-Free SrTiO3-Based Material
| Autor: | Takanobu Kajino, Yuji Yoshiyama, Saburo Hosokawa, Hiroyuki Asakura, Hiroaki Yoto, Kazuki Tamai, Kentaro Teramura, Tsunehiro Tanaka |
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| Rok vydání: | 2021 |
| Předmět: |
Materials science
Inorganic chemistry 02 engineering and technology Platinum group 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Redox 0104 chemical sciences Catalysis Adsorption Metal free Molecule General Materials Science 0210 nano-technology NOx Perovskite (structure) |
| Zdroj: | ACS Applied Materials & Interfaces. 13:29482-29490 |
| ISSN: | 1944-8252 1944-8244 |
| DOI: | 10.1021/acsami.1c03465 |
| Popis: | Pt-based catalysts are commonly employed as NOx-trapping catalysts for automobiles, while perovskite oxides have received attention as Pt-free NOx-trapping catalysts. However, the NOx storage performance of perovskite catalysts is significantly inferior at low temperatures and with coexisting gases such as H2O, CO2, and SO2. This study demonstrates that NOx storage reactions proceed over redox site (Mn, Fe, and Co)-doped SrTiO3 perovskites. Among the examined catalysts, Mn-doped SrTiO3 exhibited the highest NOx storage capacity (NSC) and showed a high NSC even at a low temperature of 323 K. Moreover, the high NOx storage performance of Mn-doped SrTiO3 was retained in the presence of poisoning gases (H2O, CO2, and SO2). NO oxidation experiments revealed that the NSC of Co-doped SrTiO3 was dependent on the NO oxidation activity from NO to NO2 via lattice oxygen, which resulted in an inferior NSC at low temperatures. On the other hand, Mn-doped SrTiO3 successfully adsorbed NO molecules onto its surface at 323 K without the NO oxidation process using lattice oxygens. This unique adsorption behavior of Mn-doped SrTiO3 was concluded to be responsible for the high NSC in the presence of poisoning gases. |
| Databáze: | OpenAIRE |
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