Superaerophobic Electrode with Metal@Metal‐Oxide Powder Catalyst for Oxygen Evolution Reaction

Abstract

A stable and highly active oxygen evolution reaction (OER) electrode is the key for fast and robust O2 production, which is one of the essential points for various kinds of energy conversion systems, such as water splitting, lithium‐O2 battery and artificial photosynthesis. Here, superaerophobic electrodes with metal@metal‐oxide powder catalysts are shown, which demonstrate high and stable OER activity. The active‐site‐density of metal@metal‐oxide catalysts is increased over one order of magnitude than those of pure metal oxides due to the large enhancement of electrical conductivity, revealing the substantial enhancement of electrochemical OER kinetics. Furthermore, the superaerophobic property of electrodes is favorable for fast O2 desorption, which improves electrochemical active surface area (EASA) during OER. The superaerophobic electrode with metal@metal‐oxide powder catalysts provides the new insight for increase of active‐site‐density and EASA simultaneously, which are the key factors to determine the activity of OER electrode.

Oxygen Vacancy Engineering of Co3O4 Nanocrystals through Coupling with Metal Support for Water Oxidation

“…The more oxygen vacancies obtained, the highert he current output (Figure 4a,F igure S16, and Ta ble S5). [18] Moreover,t he number of active centers in the Ti + Co 3 O 4 electrode was much lower than that in the Co 3 O 4 /Ti electrode (FigureS18), as expected, even thought he loadings of Co 3 O 4 speciesw ere similar( 612.9 nmol cm À2 according to the ICP analysis, data not shown). [7,15,16] Besides capturing hydroxyl groups as already presented by the O1sX PS peak at 531.17 eV (Figure 3d), [17] the oxygen vacancies also act as active centers for further oxidation reactions.…”

Recent Advances in Non‐Precious Metal‐Based Electrodes for Alkaline Water Electrolysis

“…Yong Zhao et al. prepared Ni 2 Co 1 @Ni 2 Co 1 O x with core‐shell structure which exhibited superior OER performance compared to NiO, with an onset potential of 1.55 V and η value of 380 mV at 10 mA cm −2 in 0.1 M KOH . In a recent approach, our group discussed that vanadium doped NiFe‐LDHs could exhibit much enhanced OER activity, with an η value of 195 mV at 20 mA cm −2 in 1.0 M KOH.…”

“…Yong Zhao et al prepared Ni 2 Co 1 @Ni 2 Co 1 O x with core-shell structure which exhibited superior OER performance compared to NiO, with an onset potential of 1.55 V and η value of 380 mV at 10 mA cm À 2 in 0.1 M KOH. [112] In a recent approach, our group discussed that vanadium doped NiFe-LDHs could exhibit much enhanced OER activity, with an η value of 195 mV at 20 mA cm À 2 in 1.0 M KOH. The significantly high OER performance was attributed to the existence of high valence state of V, which could alter the electronic structure and narrow-down the band-gap thereby facilitating faster electron transfer rate with abundant active sites and enhanced conductivity.…”

Superwettability of Gas Bubbles and Its Application: From Bioinspiration to Advanced Materials

“…[57] Ni 2 Co 1 @Ni 2 Co 1 O x powder catalyst with incorporated metals had a much higher density of active sites due to the increase of electrical conductivity compared to pure oxide materials.…”