3D Noble-Metal Nanostructures Approaching Atomic Efficiency and Atomic Density Limits

Adv Mater. 2024 Jan 19:e2312140. doi: 10.1002/adma.202312140. Online ahead of print.

Abstract

Noble metals have been widely used in catalysis, however, the scarcity and high cost of noble metal motivate researchers to balance the atomic efficiency and atomic density, which is formidably challenging. This article proposes a robust strategy for fabricating 3D amorphous noble metal-based oxides with simultaneous enhancement on atomic efficiency and density with the assistance of atomic channels, where the atomic utilization increases from 18.2% to 59.4%. The unique properties of amorphous bimetallic oxides and formation of atomic channels have been evidenced by detailed experimental characterizations and theoretical simulations. Moreover, the universality of the current strategy is validated by other binary oxides. When Cu2 IrOx with atomic channels (Cu2 IrOx -AE) is used as catalyst for oxygen evolution reaction (OER), the mass activity and turnover frequency value of Cu2 IrOx -AE are 1-2 orders of magnitude higher than CuO/IrO2 and Cu2 IrOx without atomic channels, largely outperforming the reported OER catalysts. Theoretical calculations reveal that the formation of atomic channels leads to various Ir sites, on which the proton of adsorbed * OH can transfer to adjacent O atoms of [IrO6 ]. This work may attract immediate interest of researchers in material science, chemistry, catalysis, and beyond.

Keywords: amorphous noble metal oxide; atomic channel; atomic density; atomic efficiency; oxygen evolution.