Electrospun Au/CeO2 nanofibers: A highly accessible low-pressure drop catalyst for preferential CO oxidation

Abstract

Abstrac:Au/CeO 2 catalysts shaped as nanofibers were obtained by supporting Au nanoparticles (ca. 3nm) on CeO 2 nanofibers of around 200 nm diameter. The CeO 2 support was prepared by calcining electrospun polymer nanocomposite fibers with a high Ce content, then gold nanoparticles were either synthesized in situ or deposited from a suspension. The prepared catalysts were used in the preferential oxidation of CO in a hydrogen-rich stream. The catalysts prepared by deposition of preformed gold nanoparticles were less stable, and underwent sintering due to a weaker nanoparticle-support interaction. In contrast, the catalysts with Au nanoparticles synthesized in situ were active (90% conversion and 46% selectivity) and stable.The fiber-shaped catalyst was able to give maximum reactant access at a much lower pressure drop compared to the catalyst in powder form.2

Recent Progress in Well‐Controlled Synthesis of Ceria‐Based Nanocatalysts towards Enhanced Catalytic Performance

“…[ 11 ] Compared to the Au NP/CeO 2 catalyst prepared by preformed AuNP directly deposited on CeO 2 nanofi bers, Au/ CeO 2 nanofi bers catalysts showed superior activity and selectivity as well as high thermal stability for CO-PROX reaction ( Figure 39 d), which could be ascribed to the SMSI effects between Au nanoparticles and CeO 2 support together with the maximum reactant access chance at very low pressure drop. The CeO 2 fi bers support was obtained by calcininng electrospun polymer nanofi bers with a high Ce content at different temperatures.…”

“… Recently, Santamaria et al prepared Au/CeO 2 nanofibers catalysts by in situ growth of Au nanoparticles on CeO 2 fibers. The CeO 2 fibers support was obtained by calcininng electrospun polymer nanofibers with a high Ce content at different temperatures …”

“…Owing to the numerous oxygen vacancy defects and high oxygen storage capacity of ceria, [ 5 ] ceria-based nanomaterials including morphology dependent ceria nanocrystals, rare-earth doped ceria-zirconia solid solutions, and noble metalceria nanocomposites have widespread high temperature and low temperature applications as catalytically active species, promoter and support in CO oxidation, [ 6,7 ] preferential oxidation of traces of CO(PROX), [8][9][10][11] low-temperature water-gas-shift (WGS) reaction, [ 12,13 ] three-way catalysts (TWCs), [ 14,15 ] steam reforming reaction, [ 16 ] solid oxide fuel cells (SOFCs), [ 17,18 ] proton exchange membrane fuel cells (PEMFCs), [ 19 ] organic chemistry, [ 20,21 ] photocatalysts, [ 22,23 ] water treatment, [ 24,25 ] oxygen sensors, [ 26 ] and other fi elds. The activities of nanoceria catalysts can be determined by their morphologies, oxygen vacancies, interfacial structures and the type of exposed crystal surfaces, as well as the synergistic effect exhibited by nanocomposites.…”

“…Among the whole RE family, cerium (Ce) is the most abundant element on Earth making up about 0.0046 wt% of the Earth's crust. Owing to the numerous oxygen vacancy defects and high oxygen storage capacity of ceria, ceria‐based nanomaterials including morphology dependent ceria nanocrystals, rare‐earth doped ceria‐zirconia solid solutions, and noble metal‐ceria nanocomposites have widespread high temperature and low temperature applications as catalytically active species, promoter and support in CO oxidation, preferential oxidation of traces of CO(PROX), low‐temperature water–gas–shift (WGS) reaction, three‐way catalysts (TWCs), steam reforming reaction, solid oxide fuel cells (SOFCs), proton exchange membrane fuel cells (PEMFCs), organic chemistry, photocatalysts, water treatment, oxygen sensors, and other fields . On the other hand, the limited thermal stability of well‐defined structure of ceria‐based nanomaterials at high temperature would limit their real applications.…”

High‐Performance Co‐MnOx Composite Oxide Catalyst Structured onto Al‐Fiber Felt for High‐Throughput O3 Decomposition

“…According to the reported method, [62,63] pressure drop (PD) within the microfibrous-structured catalyst bed and particulate Co-MnO x (0.36)/Al 2 O 3 catalyst bed were measured in a quartz tube (i.d., 16.0 mm) with each catalyst dosage of 1.0 mL. A mixture gas of O 2 / Ar (10 vol % O 2 ) was fed into the quartz tube continuously.…”