Supported Pd based catalysts are considered as the efficient candidates for low-carbon alkane oxidation for their outstanding capability to break C-H bond. Whereas, the irreversible deactivation of Pd based catalysts ...Supported Pd based catalysts are considered as the efficient candidates for low-carbon alkane oxidation for their outstanding capability to break C-H bond. Whereas, the irreversible deactivation of Pd based catalysts was still frequently observed. Herein, we reinforced the extruded Pd nanoparticles with quantitive Pt to assemble the evenly distributed Pd Pt nanoalloy onto ferrite perovskite(Pd Pt-LCF) matrix with strengthened robustness of metal/oxide support interface. We further co-achieved the enhanced performance, anti-overoxidation as well as resistance of vapor-poisoning in durability measurement. The operando X-ray photoelectron spectroscopy(O-XPS) combined with various morphology characterizations confirms that the accumulation of surface deep-oxidation species of Pd^(4+) is the culprit for fast activity loss in exsolved Pd system, especially at high temperature of 400 ℃. Conversely, it could be completely suppressed by in-situ alloying Pd with equal amount of Pt, which helps maintain the metastable Pd^(2+)/Pd shell and metallic solid-solution core structure. The density function theory(DFT) calculations further buttress that the dissociation of C–H was facilitated on alloy/perovskite interface which is, on the contrary, resistant toward O–H bond cleavage, as compared to Pd/perovskite. Our work suggests that the modification of exsolved metal/oxide catalytic interface could further enrich the toolkit of heterogeneous catalyst design.展开更多
基金supported by the National Natural Science Foundation of China (Nos.22272136, 22202041, 22102135, 22202163,22172129)the Fundamental Research Funds for the Central Universities (No.20720220119)+3 种基金Science and Technology Project of Fujian Province (No.2022L3077)the financial support from Guangdong Basic and Applied Basic Research Fund (No.2022A1515110239)the funds from Science and Technology Projects of Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM)(No.HRTP-[2022]-3)the Fundamental Research Funds for the Central Universities (No.20720220008)。
文摘Supported Pd based catalysts are considered as the efficient candidates for low-carbon alkane oxidation for their outstanding capability to break C-H bond. Whereas, the irreversible deactivation of Pd based catalysts was still frequently observed. Herein, we reinforced the extruded Pd nanoparticles with quantitive Pt to assemble the evenly distributed Pd Pt nanoalloy onto ferrite perovskite(Pd Pt-LCF) matrix with strengthened robustness of metal/oxide support interface. We further co-achieved the enhanced performance, anti-overoxidation as well as resistance of vapor-poisoning in durability measurement. The operando X-ray photoelectron spectroscopy(O-XPS) combined with various morphology characterizations confirms that the accumulation of surface deep-oxidation species of Pd^(4+) is the culprit for fast activity loss in exsolved Pd system, especially at high temperature of 400 ℃. Conversely, it could be completely suppressed by in-situ alloying Pd with equal amount of Pt, which helps maintain the metastable Pd^(2+)/Pd shell and metallic solid-solution core structure. The density function theory(DFT) calculations further buttress that the dissociation of C–H was facilitated on alloy/perovskite interface which is, on the contrary, resistant toward O–H bond cleavage, as compared to Pd/perovskite. Our work suggests that the modification of exsolved metal/oxide catalytic interface could further enrich the toolkit of heterogeneous catalyst design.
