Tailoring Unsymmetrical‐Coordinated Atomic Site in Oxide‐Supported Pt Catalysts for Enhanced Surface Activity and Stability

Abstract

The catalytic properties of supported metal heterostructures critically depend on the design of metal sites. Although it is well-known that the supports can influence the catalytic activities of metals, precisely regulating the metal-support interactions to achieve highly active and durable catalysts still remain challenging. Here, the authors develop a support effect in the oxide-supported metal monomers (involving Pt, Cu, and Ni) catalysts by means of engineering nitrogen-assisted nanopocket sites. It is found that the nitrogen-permeating process can induce the reconstitution of vacancy interface, resulting in an unsymmetrical atomic arrangement around the vacancy center. The resultant vacancy framework is more beneficial to stabilize Pt monomers and prevent diffusion, which can be further verified by the density functional theory calculations. The final Pt-N/SnO 2 catalysts exhibit superior activity and stability for HCHO response (26.5 to 15 ppm). This higher activity allows the reaction to proceed at a lower operating temperature (100 °C). Incorporated with wireless intelligent-sensing system, the Pt-N/SnO 2 catalysts can further achieve continuous monitoring of HCHO levels and cloudbased terminal data storage.

General Synthesis of a Diatomic Catalyst Library via a Macrocyclic Precursor-Mediated Approach

“…Heterogeneous single-atom catalysts (SACs) have received tremendous research interest over the past decade. − With atomically dispersed metal centers anchored on a high-surface-area support, SACs maximize the atom utilization efficiency. More importantly, SACs possess unique electronic structures and coordination environments, − which often lead to catalytic behaviors different from their nanoparticle counterparts. − The unusual catalytic activity and selectivity of SACs have been manifested in various electro- − and thermochemical reactions. − Despite all of these merits, SACs may suffer from a lack of neighboring sites. They would show limited activities for reactions that require coadsorption of reactive species on adjacent metal centers, such as C–C dissociation. − In this regard, diatomic catalysts (DACs) are emerging as a new class of atomically dispersed catalyst. , The introduction of a second metal center near the first one would facilitate the activation of inert molecules and might break the scaling relations in many processes .…”

Emerging single atom catalysts in gas sensors

“…At the same time, it can reduce the activation energy of oxygen and enhance the electron transport capacity of the materials. 38 Besides, SAs can act as active sites to promote the adsorption and dissociation of target molecules. Due to the unsaturated coordination environment around the SAs, the active sites with high surface energy reduce the reaction barrier of molecules with the adsorbed oxygen species, thereby enabling more efficient electron mobility.…”

A composite approach to synthesize a high-performance Pt/WO3–carbon catalyst for optical and electrocatalytic applications

“…To overcome the challenges of stability and decrease the cost of the Pt catalyst, several efforts have been made for methanol oxidation reactions. Single site catalysts have wide applications in diverse reactions, 1,2 such as the oxygen reduction reaction (ORR), [3][4][5][6] nitrogen reduction reaction (NRR), [7][8][9][10] and CO 2 reduction reaction (CRR), [11][12][13] and the catalysts mostly comprise metallic NPs (Pt, Au, Ag, Ni, Co, etc.) dispersed on a suitable support.…”