Metallic Inverse Opal Frameworks as Catalyst Supports for High-Performance Water Electrooxidation.

ABSTRACT: High intrinsic activity of oxygen evolution reaction (OER) catalysts is often limited by their low electrical conductivity. To address this, we introduce copper inverse opal (IO) frameworks offering a well-developed network of interconnected pores as highly conductive high-surface-area supports for thin catalytic coatings, for example, the extremely active but poorly conducting nickel-iron layered double hydroxides (NiFe LDH). Such composites exhibit significantly higher OER activity in 1 m KOH than NiFe LDH supported on a flat substrate or deposited as inverse opals. The NiFe LDH/Cu IO catalyst enables oxygen evolution rates of 100 mA cm^-2 (727±4 A g_catalyst ^-1 ) at an overpotential of 0.305±0.003 V with a Tafel slope of 0.044±0.002 V dec^-1 . This high performance is achieved with 2.2±0.4 μm catalyst layers, suggesting compatibility of the inverse-opal-supported catalysts with membrane electrolyzers, in contrast to similarly performing 10³ -fold thicker electrodes based on foams and other substrates.

SUBMITTER: Nguyen TD 

PROVIDER: S-EPMC9825931 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature