Modulating the Electrocatalytic Performance of Palladium with the Electronic Metal–Support Interaction: A Case Study on Oxygen Evolution Reaction

Abstract

The present work reports a general approach to improve the electrocatalytic property of noble metal through regulating its electron status by introducing the electronic metal–support interaction (EMSI). As a case study, the catalytic activity of metallic Pd toward oxygen evolution reaction (OER) in alkaline solution has been significantly promoted by stabilizing Pdδ+ oxidic species at the interface of the Pd–metal oxide support with the help of EMSI effect, suggesting an intrinsic advantage of Pdδ+ in driving OER. We further demonstrate that the chemical state of Pdδ+ can be easily modulated in the range of 2+ to 3+ by changing the metal oxide support, interestingly, accompanied by a clear dependence of the OER activity on the oxidation state of Pdδ+. The high Pd3+ species-containing Fe2O3/Pd catalyst has fed an impressively enhanced OER property, showing an overpotential of 383 mV at 10 mA cm–2 compared to those of >600 mV on metallic Pd and 540 mV on Fe2O3/glassy carbon. The greatly enhanced OER performance is believed to primarily derive from the distinctive improvement in the adsorption of oxygenated intermediates (e.g., *OH and *OOH) on metal-oxide/Pd catalysts. Moreover, similar EMSI induced improvements in OER activity in alkaline solution are also achieved on both of the Fe2O3/Au and Fe2O3/Pt, which possess the oxidic species of Au3+, and Pt2+ and Pt4+, respectively.

Effects of Metal Electrode Support on the Catalytic Activity of Fe(oxy)hydroxide for the Oxygen Evolution Reaction in Alkaline Media

“…He et al. studied the metal‐support interaction of drop‐cast Fe 2 O 3 on Pd and found that OER activity increased compared to the bare Pd electrode . Recently, Kauffman et al.…”

Engineering the Metal/Oxide Interface of Pd Nanowire@CuOx Electrocatalysts for Efficient Alcohol Oxidation Reaction

“…Thanks to the efficient desorption of CO ads ‐like poisoning species at SnO x ‐Pt interface sites, SnO x /Pt(111) catalyst exhibited significant promotion of the catalytic performance toward EOR. Specially, He et al reported a series of similar metal‐oxide/Pd geometric nanostructures for oxygen evolution reaction (OER) in an alkaline solution. They demonstrated that the high valence Pd δ+ species located at the metal oxide‐Pd interfaces yield more additional d‐band vacancies, resulting in an improved adsorption of oxygenated species on surface and eventual enhanced OER activity.…”

The effect of nanoparticulate PdO co-catalysts on the faradaic and light conversion efficiency of WO3 photoanodes for water oxidation

“…In addition to the contrasting effects on band bending in WO 3 , the different oxidation states of Pd would result in different bonding and adsorption properties of oxygenated intermediates that drive water oxidation. 17,37 The charge extraction characteristics of the photoanodes were assessed by TPC measurements, whereby the charge extracted was measured as a function of time following excitation by a laser pulse (Figure 4). Pd(A)/WO 3 exhibits faster charge extraction rates than bare WO 3 , whilst charge extraction in Pd/WO 3 is slower.…”

“…An additional annealing step, post Pd deposition, is undertaken to investigate the recognised effects of co-catalyst oxidation state on performance. 17 We identify PdO as a promising OEC for acidic conditions that enhances the water oxidation activity and selectivity of WO 3 towards oxygen evolution, to yield an impressive FE of 92%. Further investigations into the photoanodes, including the charge carrier properties using transient techniques, reveal the role of PdO in inducing favourable band bending and tuning oxygen vacancy concentrations in WO 3 , to consequently improve electron transport through the nanoneedles.…”