Electron Delocalization and Transfer Across Polyoxometalates-Based Subnanomaterials in Catalytic Reactions

Due to their identical building blocks and high surface-to-volume ratio, subnanomaterials exhibit significant properties compared to their bulk nanomaterial counterparts. The interactions between these building blocks can result in either equal or unequal sharing of electrons, leading to electron transfer in heterojunctions or electron delocalization within symmetric structures. Clusters, possessing electronic properties akin to atoms, can serve as reservoirs of electrons to stabilize crucial intermediates in catalytic reactions. This perspective provides a novel understanding of well-defined subnanomaterials with distinct architectures, such as cluster-based constructions and co-assembled heterojunctions, emphasizing the relationship between electronic structures and catalytic properties. The objective is to provide novel perspectives on the realm of subnanomaterials and cluster-based architectures.

Construction of a Novel Cascade Electrolysis-Heterocatalysis System by Using Zeolite-Encaged Ultrasmall Palladium Catalysts for H2 O2 Generation

In situ generation of hydrogen peroxide (H₂ O₂ ) has attracted extensive attention, especially in water treatment. However, traditional anthraquinones can only produce high-concentration H₂ O₂ and its transportation and storage are not convenient and dangerous. Herein, an in situ and on-demand strategy to produce H₂ O₂ by using a cascade water electrolysis together with a heterocatalysis system is provided. Beginning with water, H_2, and O₂ can be generated via electrolysis and then react with each other to produce H₂ O₂ immediately on efficient zeolite-encaged ultrasmall Pd catalysts. Significantly, the H₂ O₂ generation rate in the optimized cascade system reaches up to 0.85 mol L^-1 h^-1 g_Pd ^-1 , overcoming most of the state-of-the-art catalysts in previous literature. The confinement effect of zeolites is not only beneficial to the formation of highly dispersed metal species, promoting the H₂ O₂ generation, but also inhibits the H₂ O₂ decomposition, enhancing the production yield of H₂ O₂ . In addition, the effect of electrolytes, sizes of Pd species, as well as zeolite acidity are also systematically studied. This work provides a new avenue for H₂ O₂ generation via a highly efficient cascade electrolysis-heterocatalysis system by using zeolite-supported metal catalysts. The high catalytic efficiency and green process for H₂ O₂ generation make it very promising for further practical applications.