Reduction of Cu2O nanocrystals: reactant-dependent influence of capping ligands and coupling between adjacent crystal planes

Abstract

A systematic study of the reduction behavior of various types of uniform Cu 2 O nanocrystals reveals that the surface blocking effect exerted by the capping ligand on the reduction behavior of the Cu 2 O nanocrystals depends not only on the type of capping ligand but also on the reactant and that coupling between adjacent crystal planes occurs for Cu 2 O nanocrystals exposing two types of crystal planes during the reduction reactions and exerts great influence on the reduction kinetics of the involved crystal planes.

Reduction of Nano-Cu2O: Crystallite Size Dependent and the Effect of Nano-Ceria Support

“…[1][2][3] Cu 2 O has a direct band gap of 2.2eV and is used in electronic devices and as photocatalysts. 4 Although reduction studies have been conducted on Cu 2 O, [5][6][7][8][9][10] few have investigated the reduction dynamics as affected by their crystal sizes. For nanomaterials, the size-effect, such as larger surface-to-volume ratio and more active surfacesites, has a profound influence on their chemical activity and electrical performance, compared to their bulk counterparts.…”

Tailoring the reducibility and catalytic activity of CuO nanoparticles for low temperature CO oxidation

“…[47][48][49][50][51] We have thus investigated the reduction behaviors of the prepared CuO catalysts to evaluate their reducibility in CO atmosphere. Fig.…”

Surface Chemistry and Catalytic Properties of Well-Defined Cu2O Nanocrystals

“…Two factors determine the reactivity of a solid particle in the gas-solid chemical reactions: the surface reactivity of the solid particle and the adsorption/activation of gas molecules on the solid particle surface. As shown in Figure 10 [129]. This has been directly observed employing model catalyst approaches [7][8][9] and points to an important concept that the reaction kinetics of a polycrystalline particle cannot be regarded as a simple superposition of the contributions from each individual crystal plane exposed on its surface.…”

“…This demonstrates that Cu 2 O(111) surface is much more facile to be reduced than Cu 2 O(100) surface. We have comparatively studied the reducibility of the same type of crystal plane exposed on Cu 2 O nanocrystals with different morphologies [129]. On one hand, the sur- A common phenomenon occurring during the heterogeneous catalytic reaction catalyzed by a polycrystalline particle exposing various types of crystal planes is the coupling between adjacent crystal planes with different catalytic activities by the migration of surface species.…”

“…Adapted from Ref [129]. The H 2 -TPR and CO-TPR profiles of octahedra capped with PVP (o-Cu 2 O-PVP) were also included for comparisons.…”