Tunable Interfacial Electronic Pd–Si Interaction Boosts Catalysis via Accelerating O₂ and H₂O Activation

Abstract

Engineering the interfacial structure between noble metals and oxides, particularly on the surface of non-reducible oxides, is a challenging yet promising approach to enhancing the performance of heterogeneous catalysts. The interface site can alter the electronic and d-band structure of the metal sites, facilitating the transition of energy levels between the reacting molecules and promoting the reaction to proceed in a favorable direction. Herein, we created an active Pd–Si interface with tunable electronic metal–support interaction (EMSI) by growing a thin permeable silica layer on a non-reducible oxide ZSM-5 surface (termed Pd@SiO2/ZSM-5). Our experimental results, combined with density functional theory calculations, revealed that the Pd–Si active interface enhanced the charge transfer from deposited Si to Pd, generating an electron-enriched Pd surface, which significantly lowered the activation barriers for O2 and H2O. The resulting reactive oxygen species, including O2 –, O2 2–, and −OH, synergistically facilitated formaldehyde oxidation. Additionally, moderate electronic metal–support interaction can promote the catalytic cycle of Pd0 ⇆ Pd2+, which is favorable for the adsorption and activation of reactants. This study provides a promising strategy for the design of high-performance noble metal catalysts for practical applications.

Abnormal inhibiting effect of H2O on Pd/SiO2 and Na–Pd/SiO2 catalysts for HCHO oxidation

“…The peaks at low temperature (400–500 °C) were ascribed to active OH groups, which were related to the Pd species, and attributed to the interfacial OH groups of the Pd and SiO 2 carrier. 37 The peaks at 600–900 °C were assigned to intrinsic Si–OH of SiO 2 (confirmed by experimental data shown in Fig. S8†).…”

Construction of a Metal–Silica Interface for Semihydrogenation of Alkynes

“…Generally, SiO 2 is identified as an inert component of the catalysts to disperse and support metal nanocrystals. Studies indicated that the newly constructed metal–Si interface, accompanied by charge transfer, displayed superior catalytic performance in diverse important reactions, such as hydrogenation/dehydrogenation, ,− O 2 activation, electrocatalytic reactions, , and CO 2 conversion. ,, …”

Construction of C–X (X = N, O) bonds from benzyl alcohols via Cu-BTC-catalyzed oxidative coupling

“…22 Recently, MOFs have attracted much attention in various fields such as gases, supercapacitors, dye adsorption and drug delivery due to their unique structural and chemical properties. 23 Especially in catalysis, MOFs, as emerging porous nonhomogeneous catalysts, show remarkable potential 24 in reactions such as oxidations, 25 reductions, 26 couplings 27 and cyclisations. 28 [Cu 3 (BTC) 2 (H 2 O) 3 ] n (Cu-BTC, HKUST-1), as a typical representative of MOFs, has been widely used in a variety of organic reactions, 29 including couplings, 30 cyclizations, 31 oxidizations 32 and boronation reactions.…”