Pd@SBA-15 nanocomposite catalyst: Synthesis and efficient solvent-free semihydrogenation of phenylacetylene under mild conditions

Extended architectures constructed of thiourea‐modified SBA‐15 nanoreactor: A versatile new support for the fabrication of palladium pre‐catalyst

“…As shown in Figure d, the Pd NPs in Pd@BTU‐SBA‐15d was found to be ultra‐small, having an average size ranging from 1.8 to 4 nm. When only SBA‐15 was utilized instead of the BTU‐functionalized SBA‐15 for the deposition of Pd NPs, particle sizes of greater than 5.5 nm in the nanoreator were found . Also, SEM–EDS analysis was performed for the mesoporous materials.…”

A protector-free one-pot strategy to synthesize highly dispersed Pd hydrogenation catalysts in a broad loading range on polystyrene

“…According to the constructive comments of a reviewer, we have reported the features of some typical methods in literature to prepare Pd nanocatalysts and these features are shown in Table 2. In comparison with the various inorganic materialsupported Pd nanocatalysts, [22][23][24][25][26][27][28] the researches focused on the fact that Pd catalysts supported by organic materials just occupied a small fraction, 29,30 which might attribute to the relatively higher thermal stability of inorganic materials compared to that of the PS-like polymer materials. However, this thermal stability of inorganic supports also implied the inconvenience in adjusting their state, especially the surface state that would signicantly impact the conjunctive function with metal components.…”

“…For instance, the higher temperatures were always required for preparing or processing oxide or zeolite-supported metal nanocatalysts to the desired active state. [22][23][24][25][26] At high temperatures, there was inevitable thermodynamic tendency of isolated metals to leach or agglomerate, leading to the difficulty in controlling the particles within narrow nanoscale. [23][24][25] In addition, although some inorganic supports such as active carbon materials possessed rich functional groups on the surface and their nature could be easily manipulated at a proper temperature for optimizing the interaction with the loaded metal, controlling the size distribution of particles was still difficult 27,28 due to the uneven dispersing density of the functional groups on the surface, especially when metal loadings were altered to a relative higher amount.…”

“…Mimic size-dependent catalytic performance of Pd catalysts for the selective hydrogenation of phenylacetylene could be also found in literature. The styrene yields with the corresponding size of Pd particles in various catalysts [22][23][24][25][26][27][28][29][30] are listed in Table 2; in general, employing smaller Pd particles as catalysts could be more benecial to obtain higher styrene yields. However, note that no matter what the nature of the supports (inorganic or organic materials) was, the smallest Pd nanocatalysts such as particles around 2.0 or 1.5 nm were always present in colloid deposition systems, meaning that a signicant coverage of protectors (for instance, PVP) on the metal surface was necessary for obtaining and using these predened small Pd particles.…”

Facile One-Pot Ultrasound-Assisted Reduction Synthesis of Pd/C Nanocatalyst for Green Suzuki-Miyaura Coupling

“…In the patterns of Fig. 1a and b, the peaks appearing at 40.1°, 46.6°and 68.1°were due to the presence of face-centered cubic Pd planes (111), (200), (220) [6]. This suggests that Pd was successfully loaded on the surface of active carbon through two different reduction methods.…”