Solid Electrode Surface Research Articles

Synthesis of Porous Carbon Honeycomb Structures Derived from Hemp for Hybrid Supercapacitors with Improved Electrochemistry.

Energy storage in electrochemical hybrid capacitors involves fast faradaic reactions such as an intercalation, or redox process occurring at a solid electrode surface at an appropriate potential. Hybrid sodium-ion electrochemical capacitors bring the advantages of both the high specific power of capacitors and the high specific energy of batteries, where activated carbon serves as a critical electrode material. The charge storage in activated carbon arises from an adsorption process rather than a redox reaction and is an electrical double-layer capacitor. Advanced carbon materials with interconnecting porous structures possessing high surface area and high conductivity are the prerequisites 1128to qualify for efficient energy storage. Herein, we have demonstrated that a porous honeycomb structure activated carbon derived from Australian hemp hurd (Cannabis sativa L.) in aqueous Na2SO4 electrolyte showed a specific capacitance of 240 F/g at 1 A/g. The mass ratio of biochar to KOH during the chemical activation associated with the synthesis temperature influences the change in morphologies, and distribution of pore sizes on the adsorption of ions. At higher synthesis temperatures, the tubular form of the honeycomb starts to disintegrate. The hybrid sodium-ion device employing hemp-derived activated carbon (HAC) coupled with electrolytic manganese dioxide (EMD) in an aqueous Na2SO4 electrolyte showed a specific capacitance of 95 F/g at 1 A/g having a capacitance retention of 90 %. The hybrid device (HAC||EMD) can possess excellent electrochemical performance metrics, having a high energy density of 38 Wh/kg at a power density of 761 W/kg. Overall, this study provides insights into the influence of the activation temperature and the KOH impregnation ratio on morphology, porosity distribution, and the activated carbon's electrochemical properties with faster kinetics. The high cell voltage for the device is devoted to the EMD electrode.

The rise of electrochemical surface science: From in situ interface structure to operando dynamics

Surface science studies of electrochemical interfaces and processes have gained increasing popularity in the last decades, owning to the increasing importance of electrochemistry for key technologies of the 21th century, especially in electric energy storage and conversion. In situ and operando surface-sensitive methods, such as scanning probe microscopy and surface X-ray diffraction, as well as complementary ab initio theory can provide atomic-scale information on solid electrode surface in contact with liquid electrolytes, including structural changes under reaction conditions. The level of detail obtainable by these approaches is illustrated in this short review for selected examples. These include the adsorption of sulfate and other oxyanions, where a crucial role of coadsorbed water is found, the restructuring of Cu electrode surfaces under hydrogen evolution and CO2 reduction conditions, and the mechanisms of electrochemical Pt oxidation and its correlation with Pt dissolution.

Breaking Free - Unlocking the Potential of Dynamic Hydrogen Bubble Templating Materials

In recent years, porous electrodes for electrochemical conversion devices, such as low-temperature fuel cells or water electrolyzers, have been engineered to address issues related to mass transport to and within the catalyst. For example, the addition of a layer with reduced pore size facing the catalyst layer (i.e., microporous layer) results in an increased performance[1–3]. Furthermore, chemical[4], as well as mechanical[5,6]. methods of creating dedicated liquid and gas pathways in the porous electrodes, have been investigated with promising results, highlighting the need for further optimization of state-of-the-art materials with regards to multi-phase transport. The range of possible modifications is intrinsically limited by the microstructure of the material they are applied to and add cost and complexity to the already costly electrode production procedure, motivating the development of novel materials which contain these desired features, offer a large morphological design space, and are cost competitive.To tackle these stringent targets, we investigate the dynamic hydrogen bubble templating (DHBT) method to generate hierarchical structures containing both a pore size gradient as well as dedicated water and gas pathways in the form of bimodal pore size distributions. It leverages simultaneous deposition of a metal and gas evolution on the same surface to form complex structures from solution using electricity. It results in a hierarchical structure of primary pores (~5-40 µm) separated by porous walls containing secondary pores (10-1000 nm) . This type of material has been used successfully to improve boiling heat transfer[7], another process limited by the counterflow of liquid and gas. They have also been investigated as high surface area material for microbial anodes[8] and have been postulated to be appealing in other electrochemical devices such as batteries or fuel cells[9]. A significant hurdle to unlock the full potential of DHBT foams is the attachment of the foam to the solid electrode surface it is generated on. The presence of the electrode blocks the transport of media in the through-plane direction of the foam and thereby prevents its use in many electrochemical applications. Due to its fragile nature, separation of the foam from this surface easily damages the structure, which is why previous research was done exclusively in the presence of the electrode. Overcoming this limitation would enable new applications for DHBT foams and has the potential to address a wide range of problems in electrochemical systems related to porous media.In this talk, I will discuss our work towards creating free-standing, hierarchically structured metal electrodes through DHBT and the developments needed to adapt this material for the use in electrochemical systems. Owing to its well-studied synthetic parameters and facile electrodeposition, we chose copper foams to advance DHBT materials in terms of characterization and mechanical properties. As a key step of the synthesis route, we realized a method to manufacture free-standing sheets from this material from copper metal while preserving its delicate microstructure. This was supported by an optimization of synthesis parameters to improve and ensure adequate mechanical stability of the freestanding foams after isolation. This development enables the application of a wide range of characterization methods such as XTM, BET, SEM and interferometry and I will discuss how the synthesis parameters link to the resulting material microstructure. Building on this initial success, current work focuses on the transferring this knowledge to the synthesis of foams made from other metals which are more relevant to electrochemical applications such as nickel for the use in alkaline electrolyzers and paves the way to develop DHBT material into the next generation transport layer for electrochemical systems.

Practical Development of Electrochemical Sensors and Redox Flow Batteries Based on Nanostructured Design Strategy of Solid Electrode Surface

Practical Development of Electrochemical Sensors and Redox Flow Batteries Based on Nanostructured Design Strategy of Solid Electrode Surface

Gold Nanoparticle (Au NP)-Decorated Ionic Liquid (IL) Based Liposome: A Stable, Biocompatible, and Conductive Biomimetic Platform for the Fabrication of an Enzymatic Electrochemical Glucose Biosensor

A novel liposomal nanocomposite with biocompatibility and conductivity, Au@ILs-polysome, was fabricated and first utilized as the electrode material to immobilize the redox enzyme glucose oxidase (GOD) for the sensitive determination of glucose. Ionic liquids (ILs)-based polysome (ILs-polysome) was prepared via the radical polymerization of ILs based liposome (ILs-liposome) and improved by ion exchange with chloroauric acid to prepare Au nanoparticles (Au NPs) modified ILs based polysome (Au@ILs-polysome). The morphology, surface properties, and structure of Au@ILs-polysome were characterized; the results suggest that the nanocomposite exhibited excellent stability on the surface of solid electrodes without fusion. Electrochemical impedance spectroscopy (EIS) demonstrated that the nanocomposite had enhanced conductivity. Cyclic voltammetry (CV) shows that the direct electron transfer of GOD was achieved on the GOD/Au@ILs-polysome/GCE electrode since the Au@ILs-polysome provided a biocompatible microenvironment that made the immobilized enzyme stay natural and active. Differential pulse voltammetry (DPV) demonstrates that the GOD/Au@ILs-polysome/GCE electrode exhibited improved electrocatalytic activity compared with the GOD/ILs-polysome/GCE electrode. The electrochemical sensor exhibited a low detection limit of 0.02 mM, high sensitivity of 32.52 µA mM−1 cm−2, high selectivity toward glucose, and good stability. The practical application of the sensor was verified by the determination of glucose in human serum. The multi-component liposomal nanocomposites possess universal significance in protein-based direct electrochemical devices while offering a facile route to fabricating a highly sensitive glucose sensor for practical clinical diagnosis.

The Puzzling Processes at Electrode | Ionic Liquid Interface

J.M. Lehn stated in his Nobel prize lecture in 1988 that supramolecular chemistry is the chemistry of the intermolecular bond, covering the structure and functions of entities formed by the association of two or more chemical species [1]. The adsorption of organic molecules is the net result of the interactions between the molecules and the two phases, the metal and the electrolyte, and the interactions between the latter two.To this day, the universal understanding that the adsorption of organic molecules results in the formation of an ordered monolayer is based on the phenomenon observed in mainly aqueous solutions. However, the conception might not be straightforwardly transferrable to the organic additive + ionic liquid | electrode interface. For example, the existence of an interfacial multilayer structure of pure IL ions in contrast with an aqueous electrolyte has been previously shown in both experimental and computational studies. Furthermore, it has been shown that in ILs, if the ions form rigid layers on the electrode, it is necessary to apply an overpotential for interfacial restructuring. Therefore, studying the adsorption of organic additives in ionic liquids (IL) should contribute to a better understanding of metal | IL interfaces.In the given presentation we overview the characteristics of solid-liquid interface characteristics of various additives from ionic liquid media at different electrodes.Cyclic voltammetry, electrochemical impedance spectroscopy and in situ scanning tunnelling microscopy measurements were conducted to characterize the electrochemical behavior of the self-assembled layers of 4,4’-bipyridine (4,4’-BP) and 2,2’-bipyridine (2,2’-BP) at the Sb(111) | x-BP+1-ethyl-3-methylimidazolium tetrafluoroborate (EMImBF4) interface [2-3]. The specific adsorption of iodide ions was studied at Bi(111), Cd(0001) and pyrolytic graphite electrodes [4-6]. All the experiments were carried out in a three-electrode electrochemical cell in a glovebox.The halide ions are surface active ions with specific adsorption behavior [4-6]. The strong specific adsorption of halide ions at single crystal electrodes, as well as other electrodes, is a complicated process due to the partial charge transfer between adsorbed ions and the solid electrode surface. The properties of the adsorption layer depend on the electrode potential and the concentration of the surface-active ions in an electrolyte. The theory that the adsorption of organic molecules results in SAM formation is mainly based on the results observed in aqueous solutions. However, these findings may not be as straightforwardly linkable to the organic additive + ionic liquid | electrode interface. The analysis of cyclic voltammetry and impedance results revealed that 2,2′-BP and 4,4′-BP indeed adsorb at the Sb(111) interface, forming a thin dielectric layer at the electrode surface, confirmed by in situ STM measurements, resulting in the differential capacitance values nearly two times lower compared to EMImBF4. Acknowledgments:This work was supported by the Estonian Research Council grant PSG249, and by the EU through the European Regional Development Fund under project TK141 (2014-2020.4.01.15-0011).

Real‐Time Monitoring of Hydrogen Production by Water Electrolysis Using a Tapered Polarization‐Maintaining Optical Fiber Mach–Zehnder Interferometer

Gas microbubbles easily cover surface active sites of the solid electrodes in most gas evolution reactions, hindering the transfer of mass and energy and declining the reaction efficiency. However, online monitoring of gas bubbles’ behaviors on the surface of solid electrodes accurately in real time remains challenging. Herein, a tapered polarization‐maintaining fiber Mach–Zehnder interferometer for in situ monitoring of H2 bubbles detachment in water electrolysis is reported. In the experiment, the H2 bubble released from the platinum microelectrode can be detected by recording the variation of transmitted optical power in the optical fiber. By comparing it with the electrochemical measurement and the charge‐coupled device imaging, the measurement accuracy can be regarded as near 100%, and the time resolution is determined to be ≈ms. It is found that the size of the detached bubbles on the microelectrode surface is positively correlated with the electrolysis voltage. The increasing electrolysis time causes a long detachment time. Three different charged surfactants are all proved to accelerate the H2 detachment. This method is adapted to study gas bubble behaviors in various complex gas‐involving reaction systems, even for the invisible gas bubbles in a dark environment.

The Use of a Solid Bismuth Microelectrode for Vanadium Quantification by Adsorptive Stripping Voltammetry in Environmental Water Samples.

This paper presents for the first time the use of an environmentally friendly solid bismuth microelectrode for the voltammetric quantification of V(V) in natural water samples. These studies were designed to replace the film bismuth electrode that had been introduced to eliminate the conventional sensors based on highly toxic mercury. In the proposed procedure, V(V) is preconcentrated at the solid bismuth microelectrode surface via the formation of electroactive complexes with cupferron from a solution of 0.1-mol L−1 acetate buffer, pH = 4.6 at a potential of −0.4 V. The linearity of the calibration graph is in the V(V) concentration range from 8 × 10−10 to 1 × 10−7 mol L−1 with a preconcentration time of 1 min. The limit of detection (calculated as 3 σ) is 2.5 × 10−10 mol L−1 for a preconcentration time of 1 min. It was also demonstrated that significant improvement in analytical parameters was achieved as a result of the activation of the solid electrode surface at a potential of −2.5 V for 2 s. The developed procedure is highly selective for the presence of foreign ions and organic compounds in tested samples. The accuracy of the recommended procedure was checked using SPS-WW1 waste water-certified reference materials of a complex composition, in which the concentration of V(V) determined by the proposed method was 95.1 ± 1.6 ng mL−1. Moreover, in keeping with the outlined procedure, river, tap and rain water samples were analyzed without any pretreatment, and recovery values from 96% to 106% were obtained.

The oxidation of ferrocene in sessile toluene macro- and microdroplets: An opto-electrochemical study

• A simple and robust method to study phase boundary reactivity. • Optical measurements allow for precipitate visualization at phase boundaries. • Multiphysics simulations validate observations in macro- versus microdroplets. Obtaining mechanistic insight into interfacial electron and ion transfer processes remains imperative to developing a comprehensive understanding of synthetic and biological processes. There is fundamental interest in the coupled electron–ion transfer processes characteristic of heterogeneous reactions at three-phase boundaries comprised of two immiscible liquids and a solid electrode surface. To probe reactivity at the three-phase boundary, we report a multifaceted analysis of ferrocene (Fc) oxidation in toluene droplets of diverse sizes. In one experiment, we study Fc oxidation in a large toluene macrodroplet. In a second experiment, we study Fc oxidation in an array of toluene microdroplets. We performed each experiment with and without an ionic liquid, trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl)amide. Upon Fc oxidation in the oil phase without supporting electrolyte, the ferrocenium cation (Fc + ), which is soluble in water, is expelled from the oil phase to maintain charge neutrality. Because Fc is only slightly soluble in water (∼40 µM), reversing the scan to reduce Fc + in the aqueous phase generates a Fc precipitate adjacent to the three-phase boundary. This observation was confirmed by correlated optical microscopy. Increasing the voltammetric scan rate elucidated sequential versus concerted ion transfer mechanisms, which are shown to be highly dependent on the droplet size and the presence of trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl)amide in the toluene phase. Differences in voltammetric responses are supported by finite element simulations.

Direct Electrochemical Enzyme Electron Transfer on Electrodes Modified by Self-Assembled Molecular Monolayers

Self-assembled molecular monolayers (SAMs) have long been recognized as crucial “bridges” between redox enzymes and solid electrode surfaces, on which the enzymes undergo direct electron transfer (DET)—for example, in enzymatic biofuel cells (EBFCs) and biosensors. SAMs possess a wide range of terminal groups that enable productive enzyme adsorption and fine-tuning in favorable orientations on the electrode. The tunneling distance and SAM chain length, and the contacting terminal SAM groups, are the most significant controlling factors in DET-type bioelectrocatalysis. In particular, SAM-modified nanostructured electrode materials have recently been extensively explored to improve the catalytic activity and stability of redox proteins immobilized on electrochemical surfaces. In this report, we present an overview of recent investigations of electrochemical enzyme DET processes on SAMs with a focus on single-crystal and nanoporous gold electrodes. Specifically, we consider the preparation and characterization methods of SAMs, as well as SAM applications in promoting interfacial electrochemical electron transfer of redox proteins and enzymes. The strategic selection of SAMs to accord with the properties of the core redox protein/enzymes is also highlighted.

Designing of a stable and selective glucose biosensor by glucose oxidase immobilization on glassy carbon electrode sensitive to H2O2 via nanofiber interface

The integration of the enzymes on the solid electrode surfaces is an indispensable step for the construction of the bioelectrochemical electrode. In the current work, the blend nanofibers consisting of poly (vinyl alcohol) and poly(ethyleneimine) were deposited by the electrospinning method on an H2O2-sensitive modified glassy carbon electrode. Glucose oxidase was immobilized on the glutaraldehyde-activated blend nanofibers. Bioelectrochemical electrode displayed a good linear response to the glucose concentration ranges with two separate calibration curves, from 2 to 8 mmol L−1 and from 10 to 30 mmol L−1. Besides, it showed a high anti-interference performance against ascorbic and uric acids as well as long-term storage stability over 63 days. Moreover, analysis results in a diluted human serum sample showed that the prepared bioelectrochemical electrode has the ability to measure glucose in real samples.

Oxide nanolayer formation on surface of modified blast furnace sludge particles during voltammetric cycling in alkaline media

Knowledge of the properties of metallurgical waste is essential for the assessment of their recycling. In this work, the formation of iron oxide nanolayers during voltammetric cycling in 1 M NaOH on the particle surface of blast furnace sludge after acid leaching (BFSL) was studied. Most importantly, the effect of hydrogen on these processes was of particular interest. For these purposes, the study combines electrochemical methods, cyclic voltammetry on solid and carbon paste electrodes, with analytical optical methods (TEM). On the solid iron electrode surface as a model system, nanostructured magnetite (Fe3O4) was identified as the main oxidation product, and, to a lesser extent, also maghemite (γ-Fe203). It was found that the charges corresponding to Fe3O4 formation and its reduction together with the hydrogen evolution reaction (HER) occurring at E = − 1500 mV depend on the number of cycles and have a similar course. Additionally, in the first phase of the cycling, the accumulation of maghemite on the solid Fe-electrode surface during cycling affects the growth of the oxide layer and catalytically increases the yield of the HER. Concerning the measurement with BFSL-modified CPE, on the BFSL surface, haematite is transformed into magnetite during cycling, resulting in the same Fe3O4 nanolayer as on the solid iron electrode. In this layer, the same redox processes take place, including the influence of hydrogen in the initial stage of cycling.

High frequency electric discharge between jet and solid electrodes

The types and forms of combustion of electric discharges of high-frequency (HF) current with liquid and solid electrodes at atmospheric pressure are investigated. The discharge emission spectrum, plasma composition, electron concentration, and temperature of the heavy component are studied. Thermograms on the surface of liquid and solid electrodes during the combustion of the discharge are investigated.

Cultivating electroactive microbes—from field to bench

Electromicrobiology is an emerging field investigating and exploiting the interaction of microorganisms with insoluble electron donors or acceptors. Some of the most recently categorized electroactive microorganisms became of interest to sustainable bioengineering practices. However, laboratories worldwide typically maintain electroactive microorganisms on soluble substrates, which often leads to a decrease or loss of the ability to effectively exchange electrons with solid electrode surfaces. In order to develop future sustainable technologies, we cannot rely solely on existing lab-isolates. Therefore, we must develop isolation strategies for environmental strains with electroactive properties superior to strains in culture collections. In this article, we provide an overview of the studies that isolated or enriched electroactive microorganisms from the environment using an anode as the sole electron acceptor (electricity-generating microorganisms) or a cathode as the sole electron donor (electricity-consuming microorganisms). Next, we recommend a selective strategy for the isolation of electroactive microorganisms. Furthermore, we provide a practical guide for setting up electrochemical reactors and highlight crucial electrochemical techniques to determine electroactivity and the mode of electron transfer in novel organisms.

Formation and characteristics of mixed lipid/polymer membranes on a crystalline surface-layer protein lattice.

The implementation of self-assembled biomolecules on solid materials, in particular, sensor and electrode surfaces, gains increasing importance for the design of stable functional platforms, bioinspired materials, and biosensors. The present study reports on the formation of a planar hybrid lipid/polymer membrane on a crystalline surface layer protein (SLP) lattice. The latter acts as a connecting layer linking the biomolecules to the inorganic base plate. In this approach, chemically bound lipids provided hydrophobic anchoring moieties for the hybrid lipid/polymer membrane on the recrystallized SLP lattice. The rapid solvent exchange technique was the method of choice to generate the planar hybrid lipid/polymer membrane on the SLP lattice. The formation process and completeness of the latter were investigated by quartz crystal microbalance with dissipation monitoring and by an enzymatic assay using the protease subtilisin A, respectively. The present data provide evidence for the formation of a hybrid lipid/polymer membrane on an S-layer lattice with a diblock copolymer content of 30%. The hybrid lipid/polymer showed a higher stiffness compared to the pure lipid bilayer. Most interestingly, both the pure and hybrid membrane prevented the proteolytic degradation of the underlying S-layer protein by the action of subtilisin A. Hence, these results provide evidence for the formation of defect-free membranes anchored to the S-layer lattice.

Surface modification of cerasomes with AuNPs@poly(ionic liquid)s for an enhanced stereo biomimetic membrane electrochemical platform

A novel liposomal nanocomposite, Au@PIL-cerasome, with biocompatibility and conductivity was fabricated via the self-assembly of cerasomes and gold nanoparticles (AuNPs) stabilized by poly(ionic liquid)s (PILs). The surface charge, morphology and chemical composition of the nanocomposites were characterized by the zeta potential, UV–vis, TEM, SEM and EDS. The nanocomposites exhibited structural stability directly on the surface of solid electrodes, without fusion. Electrochemical impedance experiments demonstrated that the nanocomposites had an enhanced conductivity compared with unmodified cerasomes. Horseradish peroxidase (HRP), as a reporter, was immobilized on the nanocomposites without denaturation or inactivation. The direct electron transfer of HRP was achieved, and the HRP/Au@PIL-cerasome/GCE exhibited an amplified current and improved electrocatalytic activity. Activity towards H2O2 displayed a linear range over 10–70 μM and a detection limit of 3.3 μM. Activity towards NO2− displayed linear ranges over 1–5 mM and 5–1280 mM, and the limit of detection was 0.11 mM. In addition, the electrode was stable and reproducible, with 6% RSD. Such multi-component liposomal nanocomposites with an enhanced electrical performance pave a better way for building novel and straightforward 3D stereo biomimetic electrochemical platforms and even molecular communication systems to investigate information transduction between cells.

The bismuth bulk annular band electrode — a new voltammetric sensor for Al(III) traces determination

This work presents for the first time an indirect, voltammetric determination of Al(III) traces as Al-Alizarin S complex, using the environmental friendly bismuth bulk annular band electrode (BiABE). These researches were aimed at replacing the typically used sensors, based on highly toxic mercury. The differential pulse stripping voltammetric measurements were realized in relatively simple electrolyte i.e. 0.075M ammonia buffer of restrictively controlled pH equal to 9.2. It was found, that the electrode process is irreversible and controlled by both, diffusion and adsorption phenomena. The calibration graph was linear from 4 to 40μgL−1 with sensitivity of 0.20μA/μgL−1, and repeatability below 2.1%. In the Al concentration range from 0.2 to 2μgL−1 sensitivity increased to 0.54μA/μgL−1 with limit of detection 0.015μgL−1 and repeatability below 3.1%. The optimal preconcentration time was 20s. It was also demonstrated that conditioning of the solid electrode surface leads to considerable improvement of analytical parameters. The proposed method accuracy was verified using two certified reference materials of complex composition, i.e. tea leaves and surface water, in which Al(III) was determined with recoveries 99.72% and 101.86%, respectively. Additionally, due to relatively low reduction potential equal to −790mV, this sensor offers wide application capabilities regarding quantitative determination of Al(III) traces.

Bioelectrochemistry for sensing amino acids, peptides, proteins and DNA interactions

Abstract Oxidative damage to peptides, proteins and DNA is considered to be one of the major causes of cancer and age-related diseases. The interaction of biomolecules, peptides, proteins, nucleic acids and pharmaceuticals with solid electrode surfaces is not only a fundamental phenomenon but also a key to important and novel analytical sensing applications in biosensors, biotechnology, medical devices and drug-delivery schemes. Electrochemical methods can provide insight into the redox mechanisms and the electron-transfer reactions of a variety of fundamental biological processes.

Direct oxygen isotope effect identifies the rate-determining step of electrocatalytic OER at an oxidic surface

Understanding the mechanism of water oxidation to dioxygen represents the bottleneck towards the design of efficient energy storage schemes based on water splitting. The investigation of kinetic isotope effects has long been established for mechanistic studies of various such reactions. However, so far natural isotope abundance determination of O2 produced at solid electrode surfaces has not been applied. Here, we demonstrate that such measurements are possible. Moreover, they are experimentally simple and sufficiently accurate to observe significant effects. Our measured kinetic isotope effects depend strongly on the electrode material and on the applied electrode potential. They suggest that in the case of iron oxide as the electrode material, the oxygen evolution reaction occurs via a rate-determining O−O bond formation via nucleophilic water attack on a ferryl unit.

Superwetting Electrodes for Gas-Involving Electrocatalysis.

Gas-involving electrochemical reactions, including gas evolution reactions and gas consumption reactions, are essential components of the energy conversion processes and gathering elevating attention from researchers. Besides the development of highly active catalysts, gas management during gas-involving electrochemical reactions is equally critical for industrial applications to achieve high reaction rates (hundreds of milliamperes per square centimeter) under practical operation voltages. Biomimetic surfaces, which generally show regular micro/nanostructures, offer new insights to address this issue because of their special wetting capabilities. Although a series of nanoarray-based structured electrodes have been constructed and demonstrated with excellent performances for gas-involving electrochemical reactions, understanding of bubble wetting behavior remains elusive. In this Account, our recent works including understanding the way to achieve the superwetting properties of solid electrode surfaces, and our advanced design and fabrication of superwetting electrodes for different types of electrochemical gas-involving electrochemical reactions are summarized. To begin, we first put forward several criteria of superwetting surfaces, including superaerophobic surfaces and superaerophilic surfaces. Then, we discuss how the nanoarray-based surface engineering technology can achieve the superwetting properties, in which high roughness of the nanoarray architecture is discovered to be a critical factor for constructing superaerophobic and superaerophilic surfaces. Finally, the feasibility of superwetting electrodes for enhancing the performances of gas-involving electrochemical reactions is also analyzed. Based on theoretical guidance, a series of superaerophobic and superaerophilic electrodes with various methods, such as hydrothermal reactions, electrodeposition technology and high-temperature vapor phase growth, have been built for practice. By comparing with the traditional planar electrodes fabricated by drop-casting method, the superaerophobic electrodes afford a low adhesion force to gas products and accelerate gas bubbles evolution, resulting in fast current increase and stable current for gas evolution reactions. This phenomenon is confirmed by operating different gas evolution reactions (hydrogen evolution, oxygen evolution and hydrazine oxidation) using superaerophobic electrodes with different catalysts (e.g., MoS2, Pt and Cu). On the other side, the superaerophilic electrodes can improve the catalytic performance of gas consumption reaction (e.g., oxygen reduction reaction) by facilitating gas diffusion and electron transport. Following theoretical analyses and experimental demonstrations, we assemble several energy conversion systems (e.g., electrochemical water splitting and direct hydrazine fuel cells) based on superwetting electrodes and test their performances. By virtue of the structural advantages of electrodes, these energy conversion systems show much higher energy efficiencies than their counterparts. In the last section, we put forward several future fields which are worthy for further exploration as rational extensions of the superwetting electrodes.