Preparation of Magnetically Recyclable Yolk/Shell Fe_xO_y/PdPt@CeO₂ Nanoreactors with Enhanced Catalytic Activity

Abstract

Noble metal nanoparticles (NPs) have recently received considerable attention from researchers working in the field of catalysis. However, the development of new methods allowing these materials to reach their maximum catalytic properties remains challenging. Nanoreactors could lead to dramatic improvements in activity with the help of the intrinsic confinement effect. In this study, we designed a series of yolk/shell Fe O /PdPt@CeO composites, where the Fe O NPs acted as a movable core, allowing for the uniform distribution of the PdPt alloys on the inner surface of the CeO shell. The high porosity and existence of hollow voids in the CeO shell allowed these Fe O /PdPt@CeO composites to be used as nanoreactors in catalytic reactions. As well this confinement effect, we identified two structural features that led to enhanced catalytic activity, including (i) the replacement of monometallic NPs with a bimetallic PdPt alloy and (ii) the replacement of a chemically inert support with a reactive CeO shell. The resulting nanoassembled catalysts displayed higher activities toward the catalytic reduction of dyes than the reference samples. Moreover, these catalysts were readily recovered and reused because of the magnetic Fe O core.

Modulating the Energy Band Structure of the Mg-Doped Sr0.5Pr0.5Fe0.2Mg0.2Ti0.6O3−δ Electrolyte with Boosted Ionic Conductivity and Electrochemical Performance for Solid Oxide Fuel Cells

“…Figure e shows the Fe 2p spectra, where Fe 2+ 2p 1/2 and Fe 2+ 2p 3/2 are situated at 709.2 and 722 eV, respectively, and Fe 3+ 2p 1/2 and Fe 3+ 2p 3/2 are situated at 710.963 and 725.1 eV, respectively . In addition, the Fe 4+ 2p 1/2 and Fe 4+ 2p 3/2 peaks are also associated with the BEs of 712.96 and 725.31 eV, respectively, with a satellite peak at 717.9 eV . These findings indicate that Fe 2p exists in three different oxidation states (Fe 2+ , Fe 3+ , and Fe 4+ ) at their respective BEs, as shown in Figure e, and there are different percentages of Fe 2p oxidation states in each material.…”

“…39 In addition, the Fe 4+ 2p 1/2 and Fe 4+ 2p 3/2 peaks are also associated with the BEs of 712.96 and 725.31 eV, respectively, with a satellite peak at 717.9 eV. 40 These findings indicate that Fe 2p exists in three different oxidation states (Fe 2+ , Fe 3+ , and Fe 4+ ) at their respective BEs, as shown in Figure 2e, and there are different percentages of Fe 2p oxidation states in each material. Moreover, the Fe 2p peaks in SPFMg 0.2 T are shifted to a lower BE, and a BE downshift of 0.75 ± 0.05 eV was observed in SPFMg 0.2 T compared to that in SPFT.…”

A simple approach for synthesis of hollow mesoporous nanotubes loaded with metallic and magnetic nanoparticles: Only one step is required

“…The high‐resolution Pd 3d spectrum in Figure b exhibits four individual peaks. The peaks at 343.0 and 373.7 eV correspond to Pd 2+ of PdO, while the peaks at 340.8 and 335.5 eV are assigned to metallic Pd 0 . The peak area of PdO is 44.7%, due to the synthesis of Pd 0 in a highly oxidative environment.…”

Highly Active Interfacial Sites in SFT‐SnO2 Heterojunction Electrolyte for Enhanced Fuel Cell Performance via Engineered Energy Bands: Envisioned Theoretically and Experimentally

“…[ 53 ] While 713.3 and 725.1 eV are accredited to Fe 4+ ‐2p 3/2 and Fe 4+ ‐2p 1/2 , respectively. [ 54 ] It can be seen that the peak intensity and percentage of Fe 2+ , Fe 3+ , and Fe 4+ are different in each sample as well Fe‐2p shifted slightly with 0.92 ± 12 eV. Considering the peak areas of singlet curve, the calculated average valence contribution of Fe‐2p are 3.08 and 2.92 for SFT and SFT‐SnO 2 , respectively.…”