Research on assembly of nano-Pd colloid and fabrication of supported Pd catalysts from the metal colloid

Promoting Effect of Bismuth Oxide on Palladium for Low‐Temperature Carbon Monoxide Oxidation

“…Similarly, a small negative peak at 78 °C and a similar broad peak between 88 and 168 °C are found for the Pd&Bi(1.4)/TiO 2 ‐N catalyst. From the results of compounds with the same Pd loading but different H 2 release and consumption amounts (Table S3), it is reasonable to assume that some of the PdO species is reduced during the flow of H 2 at room temperature, which adsorbs some H 2 and releases it during temperature‐programmed desorption (TPD) below 100 °C . Several major positive peaks at 470, 710, and 755 °C are further observed for Pd/TiO 2 ‐N and Pd&Bi(1.4)/TiO 2 ‐N, of which the former can be assigned to the reduction of TiO 2 ‐N (Ti 4+ to Ti 3+ ) caused by the spillover effect, and the latter two to the partial reduction of the surface capping oxygen of TiO 2 ‐N .…”

“…From the results of compoundsw ith the same Pd loading but different H 2 release and consumption amounts (Table S3), it is reasonable to assume that some of the PdO speciesi sr educed during the flow of H 2 at room temperature,w hich adsorbs some H 2 and releases it during temperature-programmed desorption (TPD) below 100 8C. [46] Several major positive peaks at 470, 710, and 755 8Ca re furthero bserved for Pd/ TiO 2 -N and Pd&Bi(1.4)/TiO 2 -N, of whicht he former can be assigned to the reductiono fT iO 2 -N (Ti 4+ + to Ti 3+ + )c aused by the spillovere ffect,a nd the latter two to the partial reduction of the surface capping oxygen of TiO 2 -N. [47][48][49][50][51] Slight but crucial differences between Pd/TiO 2 -N and Pd&Bi(1.4)/TiO 2 -N suggest ad iscriminatory interaction between bismuth oxide and Pd species. This can be supported by the H 2 -TPR curveso fP d/ Bi(x)-TiO 2 -N samples ( Figure S6).…”

Effect of Zirconium Precursor on Performance of Pd/Ce0.45Zr0.45La0.1O1.95 Three-Way Catalyst

“…Considering the low loading of Pd, we speculated that the support also took part in the reduction process. This could occur because the presence of a noble metal could promote the removal of the interfacial oxygen species [25]. Two other weak peaks (δ and ε) in the range of 250400 o C were also observed, which might be due to the reduction of surface/subsurface oxygen species.…”

Preparation of CexZr1-xO2 with Combined Composition for Improved Pd-only Three-way Catalyst

“…Thus, the more oxidative state of Pd species owing to the strong interaction between Pd species and the supports in Pd/Ce65i-F and Pd/Ce35i-F is partly responsible for their excellent CO/HC performance. Furthermore, the reducibility of Pd species is crucial to the CO/HC oxidation activity [18] . Thus, the better reducibility of Pd/Ce65i-F and Pd/Ce35i-F is important for the participation of PdO/Pd and Ce 4+ /Ce 3+ during CO/HC oxidation.…”