Multi-wall carbon nanotubes as support of copper–cerium composite for preferential oxidation of carbon monoxide

Self-Expansion Construction of Ultralight Carbon Nanotube Aerogels with a 3D and Hierarchical Cellular Structure

“…The isothermal adsorption–desorption curves of the CNT aerogel measured by the Brunauer–Emmett–Teller (BET) method showed a typical microporous structure of the cell walls, and demonstrated a high specific surface area of 298 m 2 g −1 (Figure b). The specific surface area of a pristine CNT film was only about 180 m 2 g −1 (Figure S2, Supporting Information), which was at the same level with those of multiwalled CNTs reported in the literature and almost one magnitude lower than those of single‐walled CNT aerogels . By performing the piranha solution treatment, the CNT aerogel obtained higher specific surface area than the pristine CNT film.…”

Heterogeneous Cu–Fe oxide catalysts for preferential CO oxidation (PROX) in H2-rich process streams

“…The high activity might be due to the small Cu + clusters which were in situ formed under hydrothermal conditions due to the chemical interaction with the CuFe 2 O 4 catalyst. 7,40,46,48 Moreover, under CO-PROX reaction conditions, Cu was found to exist as Cu + . Similar to the CuO systems reported in the literature 45,[50][51][52] Cu composite systems presented in this work has shown high activity for CO oxidation, and the strong interaction between the two metal components is believed to be responsible for the high activity.…”

“…A high activity might have therefore arisen on account of small Cu and Mn clusters, which were formed in situ under hydrothermal conditions due to the chemical reactions. 40,53,54 Moreover, under CO PROX process conditions, Cu was found to exist mainly as Cu + . Analogously to CuFe 2 O 4 systems, reported in the literature, 45,50,54,56,59 Cu-Mn composite catalysts, presented in this work (Table 4), have shown a high relative activity for CO oxidation and a strong interaction between the two metal components, believed to be responsible for the said good performance, stability-wise as well.…”

“…The CuFe 2 O 4 catalyst supported monometallic Cu or Fe catalysts show lower CO-PROX performance under identical conditions the reverse water gas shi reaction is not observed over these catalysts, in agreement with the literature. 8,40,41 The negative effect of Cu or Fe for CO-PROX may therefore be attributed to the formation of the hydroxyl group, which can selectively oxidise hydrogen to water, 7,42,43 the generation of an excess of -OH oxidising species bringing about a drop in CO 2 selectivity, and hence leading to lower CO-PROX performance. The high selectivity towards CO 2 can be attributed nely dispersed CuFe 2 O 4 phase on Al 2 O 3 as well as to the synergistic effect between Cu and Fe in CuFe 2 O 4 phase.…”

Ruthenium Catalyst Supported on Multi-Walled Carbon Nanotubes for CO Oxidation

“…However, the synthesized carbon nanotubes need pretreatment for anchoring metallic sites, promoting higher dispersion of the metallic particles [30]. Zeng et al [31] found that the hydrophilic functional groups of hydroxyl and carboxyl are favorable for the insertion of the metal oxide into the tubes of the MWCNTs. Kozonoe et al [32] synthesized recently the Ni@MWCNT/Ce catalyst and evaluated the influence of testing variables on reaction performance and nanostructure of the catalyst.…”