Pd, Cu and Bimetallic PdCu NPs Supported on CNTs and Phosphine‐Functionalized Silica: One‐Pot Preparation, Characterization and Testing in the Semi‐Hydrogenation of Alkynes

Abstract

Triphenylphosphine stabilized Pd, Cu and PdCu nanocatalysts supported on carbon nanotubes (CNTs) or phosphorus functionalised silica (P−SiO2) were prepared via a one‐pot methodology. The series of P−SiO2 supported catalysts evidenced metal particle sizes of metallic nanoparticles (M‐NPs) between 1 and 2.4 nm, smaller than their equivalents on CNTs (2.4–2.6 nm). Such a difference in particle size as a function of the support and the metallic composition indicated the more pronounced mediation of the CNTs support during the formation of the M‐NPs when compared to the P−SiO2 support. The series of supported catalysts were tested in the semi‐hydrogenation of alkynes providing differences in reactivity which might be correlated with the size and composition of the M‐NPs and the nature of corresponding support. The carbon supported catalysts displayed in general higher activities than those supported on silica and the bimetallic catalyst PdCu/CNTs were the most selective for the case of alkyl substituted alkynes. This catalyst could moreover be recycled several times without loss of activity nor selectivity.

Rational Design of Alloy Catalysts for Alkyne Semihydrogenation via Descriptor-Based High-Throughput Screening

“…Therefore, it is rational to extend the application of structural descriptors to nonclose packed surfaces, such as (100) surface. To verify the structure-performance relationship based on φ­(CH 3 /H), we plotted φ­(CH 3 /H) versus predicted and experimental data ,,− in Figures d–g and S24 . The predicted performance is pointed by the locations of these catalysts in volcano maps, and the experimental performance of corresponding samples is shown in the small bar chart.…”

Leveraging Dual‐Atom Catalysts for Electrocatalysis Revitalization: Exploring the Structure‐Performance Correlation

“…[ 67 ] In the work of Shi and coworkers, [ 57a ] a highly dispersed Pd–Cu bimetallic catalyst was synthesized on the γ‐Al 2 O 3 substrate for the electroreduction of nitrate (NO 3 ) into nitrogen (N 2 ). The Pd─Cu catalyst is typically supported on diverse substrates, such as zeolite, [ 68 ] active carbon, [ 69 ] TiO 2 , [ 70 ] CeO 2 , [ 71 ] Al 2 O 3 , [ 72 ] and SiO 2 [ 73 ] for achieving homogeneous dispersion of catalyst particles. Remarkably, the Al 2 O 3 stands out as one of the most extensively studied supports, assigned to its prowess for generating reactive Brønsted or Lewis acid sites, small particle size and extraordinary activity.…”

Mesoporous CeO2-supported ultrafine PdCu nanoparticle catalyst for selective hydrogenation of alkynols

“…[10][11][12] One of the strategies is to regulate the structure and composition of the metal active sites in the catalyst by using other metals as regulators. 13,14 Other non-precious metals, such as Co, Cu, Ni and Fe that are used to form bimetallic NPs with noble metals, can influence the structure of the noble metal active sites and the electronic structure of the active metal through electron transfer, [15][16][17][18] and further determine the binding mode and strength of the reactants/intermediates/products at the reaction center, directly affecting the selectivity of the selective hydrogenation reactions. As a low-cost metal with high electron density, copper (Cu) is often used as a secondary metal dopant to modify the physicochemical properties of the active metals.…”