A self-healing electrocatalytic system via electrohydrodynamics induced evolution in liquid metal

Abstract

Catalytic deterioration during electrocatalytic processes is inevitable for conventional composite electrodes, which are prepared by depositing catalysts onto a rigid current collector. In contrast, metals that are liquid at near room temperature, liquid metals (LMs), are potential electrodes that are uniquely flexible and maneuverable, and whose fluidity may allow them to be more adaptive than rigid substrates. Here we demonstrate a self-healing electrocatalytic system for CO2 electroreduction using bismuth-containing Ga-based LM electrodes. Bi2O3 dispersed in the LM matrix experiences a series of electrohydrodynamic-induced structural changes when exposed to a tunable potential and finally transforms into catalytic bismuth, whose morphology can be controlled by the applied potential. The electrohydrodynamically-induced evolved electrode shows considerable electrocatalytic activity for CO2 reduction to formate. After deterioration of the electrocatalytic performance, the catalyst can be healed via simple mechanical stirring followed by in situ regeneration by applying a reducing potential. With this procedure, the electrode’s original structure and catalytic activity are both recovered.

Fundamentals, Applications, and Perspectives of Liquid Metals in Catalysis: An Overview of Molecular Simulations

“…(a) Current density and Faraday efficiency of the electrochemical CO 2 reduction reaction during a 10 h electrolysis with the Bi-containing Ga-based liquid metal electrode. Panel a was reproduced with permission from ref . Copyright 2022 Springer Nature.…”

Electrically Functional Self‐Healing Polymers: Design, Assessment, and Progress

“…In addition, Wu and their group successfully prepared a new bismuth catalyst liquid metal electrode for use in the field of electrocatalytic CO 2 reduction by using liquid metal as a dispersant and inducing controllable evolution of the nanocatalyst through an electric field. [ 76 ] When the bismuth catalyst became deactivated due to prolonged use, they achieved a self‐repair process of the catalyst through in situ electrochemical reconstruction.…”

Local Order in Liquid Gallium–Indium Alloys

“…Room-temperature liquid alloys, also known as liquid metals, typically have liquidus temperatures below 300 °C and are based on the low-melting elements gallium, bismuth, indium, cesium, sodium, and mercury as majority components . More recently, liquid metals were discovered as heterogeneous catalysts with the renewable surface for CO 2 reduction , or petrol refining, templates for synthesis of 2D-materials, for tailored growth of microcrystals and as electrode material in all-liquid batteries. , In particular, gallium alloys display low-melting points, wide liquid range, low toxicity, and chemical inertness making them suitable as liquid-metal inks for flexible printed electronics , or as pumps and actuators in microfluidic devices. − A suspension of magnetic particles in liquid gallium can function as a shape-shifting miniature machine with field-assisted solid–liquid transition …”