Stabilization of Cu₂O through Site-Selective Formation of a Co₁Cu Hybrid Single-Atom Catalyst

Abstract

Single-atom catalysts (SACs) consist of a low coverage of isolated metal atoms dispersed on a metal substrate, called single-atom alloys (SAAs), or alternatively single metal atoms coordinated to oxygen atoms on an oxide support. We present the synthesis of a new type of Co1Cu SAC centers on a Cu2O­(111) support by means of a site-selective atomic layer deposition technique. Isolated metallic Co atoms selectively coordinate to the native oxygen vacancy sites (Cu sites) of the reconstructed Cu2O­(111) surface, forming a Co1Cu SAA with no direct Co–O x bonds. The centers, here referred to as Co1Cu hybrid SACs, are found to stabilize the active Cu+ sites of the low-cost Cu2O catalyst that otherwise is prone to deactivation under reaction conditions. The stability of the Cu2O­(111) surface was investigated by synchrotron radiation-based ambient-pressure X-ray photoelectron spectroscopy under reducing CO environment. The structure and reduction reaction are modeled by density functional theory calculations, in good agreement with experimental results.

Exploring Stability of Transition-Metal Single Atoms on Cu2O Surfaces

“…It is more interesting that many high-activity Cu 2 O-based SACs and SCCs have been synthesized by experiments recently, which can support our predicted high-stability models. For example, SACs can be synthesized by Pd atom-doped second layer copper on the Cu 2 O­(111) surface; SCCs can be synthesized by Co atom-doped first layer oxygen on the Cu 2 O­(111) surface; SACs can be synthesized by Rh atom-doped copper on the Cu 2 O­(100) surface . The high stability and reactivity of explored single-atom configurations doped into Cu 2 O surfaces are of topical interest in the framework of SAC and SCC catalysts, and studies of high reactivity of Cu 2 O-based SACs and SCCs are ongoing in our group.…”

High-valent iron single-atom catalysts for improved overall water splitting via a reduced energy barrier and stabilization of the active center

“…6 To increase the specific activities of the underlying electrocatalysts, one needs to consider improving the surface/interface reactive properties, reducing the size of the electrocatalysts to increase the accessible number of active sites, and stabilization of the active centres. 7,8 Despite the substantial advancements made with non-precious catalysts, 9,10 platinum (Pt)-, iridium (Ir)- and ruthenium (Ru)-based materials are considered to be the most effective catalysts for electrochemical green-hydrogen generation. 11–13 However, the high price and scarcity of state-of-the-art precious-metal-based catalysts hamper their widespread use in electrolyzers for the production of H 2 .…”

Ionic Liquid Modification of High-Pt-Loading Pt/C Electrocatalysts for Proton Exchange Membrane Fuel Cell Application

“…Improvement was demonstrated for the half-cell measurement in both liquid electrolyte and in the MEA test. In addition, metal or metal oxide nanomaterials (Cu 2 O [20,21], ZrO 2 [22], SnO 2 [23], etc.) showed a promising future as catalysts for fuel cell cathodes because of their excellent stability.…”