提交时间: 2017-04-06
摘要: A series of LaCo0.95-xFexPd0.05O3 (x = 0, 0.1, 0.2, 0.3) perovskite-type catalysts have been prepared by a modified sol-gel method. Their structures and physicochemical properties have been studied by powder X-ray diffraction (PXRD), transmission electron
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2017-05-02
摘要: Based on a bio-inspiration polydopamine reaction platform, hollow Ag/carbon microporous spheres were facilely prepared through a template-assisted method. The hollow Ag/carbon spheres, with a uniform shell thickness of 30 nm and a high Ag loading, show high catalytic activity for the reduction of 4-nitrophenol by NaBH4 to 4-aminophenol. It is found that the 4-nitrophenol (10 mL, 1 10 3 M) can be completely converted to 4-aminophenol in 2 min by adding 20 mg of hollow Ag/carbon catalysts. The catalytic activity of the hollow Ag/carbon microporous spheres is also confirmed by CO oxidation. At 200 C, 100% CO conversions can be achieved by using hollow Ag/carbon microporous spheres as catalysts, which is promising to replace other noble metal catalysts in metal catalyzed reactions.
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2017-04-06
摘要: A series of La1-xBaxCoO3(x = 0, 0.1, 0.2, 0.3) perovskites were synthesized by the modified sol-gel method, and their activities for NO oxidation were investigated as well. The relevant structural characterizations of the prepared catalysts were conducted
分类: 材料科学 >> 材料科学(综合) 提交时间: 2017-03-30
摘要: A series of La1-xBaxCoO3(x = 0, 0.1, 0.2, 0.3) perovskites were synthesized by the modified sol-gel method, and their activities for NO oxidation were investigated as well. The relevant structural characterizations of the prepared catalysts were conducted
分类: 材料科学 >> 材料科学(综合) 提交时间: 2017-03-30
摘要: A series of La1-xBaxCoO3(x = 0, 0.1, 0.2, 0.3) perovskites were synthesized by the modified sol-gel method, and their activities for NO oxidation were investigated as well. The relevant structural characterizations of the prepared catalysts were conducted
提交时间: 2017-05-02
摘要: Mn-doped La0.8Sr0.2CoO3 perovskite oxides [La0.8Sr0.2Co1-xMnxO3; x = 0, 0.1, 0.3, 0.5] were synthesized by a modified sol-gel method. The phase-pure oxides were obtained. CoO and carbonates were formed on the surface of La0.8Sr0.2CoO3. With increasing dop
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2017-05-02
摘要: This study investigates the structural stability of small Pd@Pt core@shell octahedral nanoparticles (NPs) and their shell thickness dependent catalytic performance for p-chloronitrobenzene hydrogenation with H2. The 6−8 nm Pd@Pt octahedral NPs are prepared by a sequential reduction method, and the characterization results confirm that Pd@Pt octahedral NPs with one to four atomic Pt layers can be controllably synthesized. The Pd@Pt octahedral NPs with one atomic Pt layer demonstrate excellent structural stability with the maintenance of core−shell structures as well as high catalytic stability during cycle to cycle catalytic p-chloronitrobenzene hydrogenation reactions. The alumina-supported Pd@Pt octahedral NPs illustrate a superior catalytic performance relative to individual Pt and Pd and their physical mixtures. Theoretical calculations by density functional theory suggest that the unexpected structural stability for Pd@Pt octahedral NPs with thin Pt shells and their corresponding catalytic stability during hydrogenation reactions can be ascribed to the strong binding between Pt surfaces and reactants/products in catalytic reactions. The enhanced catalytic performance of Pd@Pt octahedral NPs possibly originates from the core−shell interaction, which adjusts the electronic state of surface Pt atoms to be suitable for selective p-chloronitrobenzene hydrogenation.