We have investigated the release of active sites blocked by bubbles attached on the surface of catalysts during the oxygen evolution reaction (OER) in alkaline water electrolysis, via the modulation of the wetting properties of the four different morphologies of a nickel catalyst.

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Self-terminating electrodeposition was used to grow ultrathin Pt overlayers on 111 textured Au thin films. The Pt thickness was digitally controlled by pulsed potential deposition that enabled the influence of overlayer thickness on electrocataytic reactions, such as methanol and formic acid oxidation, to be examined. Bimetallic and ensemble effects associated with submonolayer coverage of Pt on Au yield enhanced catalysis. For films grown using one deposition pulse, the peak rate of CH3OH oxidation was enhanced by a factor of 4 relative to bulk Pt. The overlayer consisted of 2 nm diameter monolayer Pt islands that covered 75% of the surface; however, voltammetric cycling resulted in a loss of the enhanced activity associated with the as-deposited submonolayer films. For thicker Pt films, the electrocatalytic activity decreased monotonically with thickness until bulk Pt behavior was obtained beyond three monolayers. For HCOOH oxidation improvements in the Pt area, normalized activity in excess of a 100-fold were observed for submonolayer Pt films. The performance improved with voltammetric cycling as a result of a combination of Pt dissolution, Au segregation, and Pt–Au alloy formation. The maximum activity was associated with fractional surface coverage between 0.28 and 0.21, although the films were subject to a deactivation process at longer times related to a diffusional process. Bulk Pt behavior for formic acid oxidation was observed for Pt films greater than three monolayers in thickness.

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Electrochemical carbon dioxide (CO2) reduction is considered to be an efficient strategy to produce usable fuels and overcome the concerns regarding global warming. For this purpose, an efficient, earth abundant, and a low cost catalyst has to be designed. It has been found that graphene‐based materials could be promising candidates for CO2 conversion because of their unique physical, mechanical, and electronic properties. In addition, the surface of graphene‐based materials can be modified by using different strategies, including doping, defect engineering, producing composite structures, and wrapping shapes. In this review, the fundamentals of electrochemical CO2 reduction and recent progress of graphene‐based catalysts are investigated. Furthermore, recent studies on graphene‐based materials for CO2 reduction are summarized.

This study details a “wet” atomic layer deposition process that uses potential modulation and H adsorption to terminate Ir deposition at high deposition overpotentials. The ultrathin Ir films match or exceed the best reported electrocatalytic activity for the oxygen evolution reaction (OER) and hydrogen production and oxidation reaction (HER and HOR) on bulk Ir electrodes.