Activation and Spillover of Hydrogen on Sub‐1 nm Palladium Nanoclusters Confined within Sodalite Zeolite for the Semi‐Hydrogenation of Alkynes

The search for efficient nontoxic catalysts able to perform industrial hydrogenations is a topic of interest, with relevance to many catalytic processes. Herein, we describe a mechanistic phenomenon for the activation and spillover of hydrogen for remarkable selectivity in the semi‐hydrogenation of acetylene over sub‐1 nm Pd nanoclusters confined within sodalite (SOD) zeolite (Pd@SOD). Specifically, hydrogen is dissociated on the Pd nanoclusters to form hydrogen species (i.e., hydrogen atoms and hydroxyl groups) that spill over the SOD surfaces. The design and utilization of the small‐pore zeolite SOD (six‐membered rings with 0.28×0.28 nm channels) is crucial as it only allows H₂ diffusion into the channels to reach the encapsulated Pd nanoclusters and thus avoids over‐hydrogenation to form ethane. Pd@SOD exhibits an ethylene selectivity of over 94.5 %, while that of conventional Pd/SOD is approximately 21.5 %.     

Engineering of Ruthenium–Iron Oxide Colloidal Heterostructures: Improved Yields in CO2 Hydrogenation to Hydrocarbons

Catalytic CO₂ reduction to fuels and chemicals is a major pursuit in reducing greenhouse gas emissions. One approach utilizes the reverse water‐gas shift reaction, followed by Fischer–Tropsch synthesis, and iron is a well‐known candidate for this process. Some attempts have been made to modify and improve its reactivity, but resulted in limited success. Now, using ruthenium–iron oxide colloidal heterodimers, close contact between the two phases promotes the reduction of iron oxide via a proximal hydrogen spillover effect, leading to the formation of ruthenium–iron core–shell structures active for the reaction at significantly lower temperatures than in bare iron catalysts. Furthermore, by engineering the iron oxide shell thickness, a fourfold increase in hydrocarbon yield is achieved compared to the heterodimers. This work shows how rational design of colloidal heterostructures can result in materials with significantly improved catalytic performance in CO₂ conversion processes.     

Investigation of the Support Effect in Atomically Dispersed Pt on WO3−x for Utilization of Pt in the Hydrogen Evolution Reaction

Single‐atom catalysts (SACs) have attracted growing attention because they maximize the number of active sites, with unpredictable catalytic activity. Despite numerous studies on SACs, there is little research on the support, which is essential to understanding SAC. Herein, we systematically investigated the influence of the support on the performance of the SAC by comparing with single‐atom Pt supported on carbon (Pt SA/C) and Pt nanoparticles supported on WO_3?x (Pt NP/WO_3?x). The results revealed that the support effect was maximized for atomically dispersed Pt supported on WO_3?x (Pt SA/WO_3?x). The Pt SA/WO_3?x exhibited a higher degree of hydrogen spillover from Pt atoms to WO_3?x at the interface, compared with Pt NP/WO_3?x, which drastically enhanced Pt mass activity for hydrogen evolution (up to 10 times). This strategy provides a new framework for enhancing catalytic activity for HER, by reducing noble metal usage in the field of SACs.