Inductive Heating for Research in Electrocatalysis: Theory, Practical Considerations, and Examples

Abstract

Inductive heating in neutral or slightly reducing gaseous atmosphere has become one of the most effective methods to thermally pretreat oxygen-sensitive monocrystalline electrodes for interfacial electrochemistry and electrocatalytic research. In this contribution, we discuss the principles and theory of inductive heating, and we explain how an alternating current passing through a coil induces a resistive current inside a conductive sample. The thermodynamics and heat transport phenomena of how the thermal energy propagates and heats the sample are then discussed. Practical considerations with examples are given about how to best utilize this technique and avoid sample damage by controlling the gaseous atmosphere surrounding the sample being treated. Finally, a Ni(111) electrode is used to demonstrate the applicability of the method to interfacial electrochemistry and electrocatalysis research. The post-thermal treatment demonstrates the effect of the presence of small amounts of oxygen in the gaseous atmosphere on cyclic voltammetry profiles acquired in aqueous alkaline media.

Surface Structure Dependence of Electrochemical Processes at Monocrystalline Nickel Electrodes. Part 1: The Hydrogen Evolution Reaction

“…Figure shows a typical cooling curve for a Ni­( hkl ) electrode measured within a 1:1 ratio of Ar­(g)/H 2 (g) with a total gas flow rate of 1.00 L min –1 . A more detailed description of how induction annealing is applied to the thermal treatment of monocrystalline electrodes is available elsewhere . As inductive heating is a contactless form of heating, the temperature begins to drop immediately as soon as the RF coil is switched off and there are no additional or lagging inputs of thermal energy, i.e.…”

“…A more detailed description of how induction annealing is applied to the thermal treatment of monocrystalline electrodes is available elsewhere. 39 As inductive heating is a contactless form of heating, the temperature begins to drop immediately as soon as the RF coil is switched off and there are no additional or lagging inputs of thermal energy, i.e., residual hot gases from a flame or hot wires from a resistive heating setup. The cooling curve shows that there is a rapid temperature drop within the first second, followed by a progressively slower drop as the Ni(hkl) electrode cools down further.…”