Mesh Electrode Research Articles

From Waste to Power: Developing Structural Supercapacitors with Red Mud and Jute Stick.

Developing effective, cost-efficient, and eco-friendly energy storage solutions is crucial for sustainable building structures. Red mud, a waste material, was used as the electrolyte and separator in supercapacitors, alongside activated carbon derived from jute sticks coated on steel mesh electrodes. Tests on RM-enhanced supercapacitors showed that 20% by weight of RM was the best amount. This increased the modulus of elasticity by 33%, the tensile strength by 3%, and the compressive strength by 10%. Durability was largely unaffected, with minimal additional water absorption and slight shrinkage variation. The supercapacitor cell had an extended cell potential of 1.5 V and a maximum specific capacitance of 62.3 F g-1 at 0.4 A g-1, as shown by electrochemical tests. This improved energy density to 19.5 Wh kg-1, with a power density of 301.8 W kg-1 at 0.4 A g-1 and a maximum power density of 605.8 W kg-1 at 0.8 A g-1. The cell retained 77% of its initial capacitance after 450 continuous GCD cycles, demonstrating notable stability. This stability is due to the solid electrolyte and the synergy between JC and RM, indicating promising advancements for future energy storage devices.

Development of Micro-Nano Structured Electrodes for Enhanced Reactivity: Improving Efficiency Through Nano-Bubble Generation

This study focuses on developing high-performance electrodes by applying micro/nano structures to aluminum mesh electrodes and evaluating their electrochemical performance through the electroflotation process. First, the most suitable electrode material for electroflotation was selected, followed by the application of micro-nano structures to analyze bubble generation and size distribution in comparison to conventional electrodes. The bubble generation rate and size were used to predict electroflotation efficiency, which was then validated through experiments. The developed electrodes demonstrated a ninefold reduction in purification time compared to traditional electrodes and achieved higher wastewater treatment efficiency than spontaneous flotation. This research highlights the potential of micro-nano structured electrodes to enhance electroflotation processes and offers valuable insights for industrial applications.

PID controller design for manipulating electrorheological valves with mesh electrodes using in 2D matrix display

Abstract The electrorheological (ER) valve with parallel electrodes structure has an inherent characteristic. The electrodes gap is the same as its flow channel gap, which causes a strong coupling relationship between the applied voltages and the flow rates of the ER valve. If flow rates of ER valves in the condition of turn on operational mode were increased, their applied voltages were increased necessarily for keeping their shutdown operational mode, which brings a bunch of problems of product costs and dimensions, especially when multiple ER valves with different operational modes work together, such as application of ER valves matrix used in 2D matrix displays. The mesh electrodes structure can decouple the relationship between the electrodes gap and the flow channel gap of parallel electrodes structure. However, due to the complexity of mesh electrodes structure, a mathematic model is difficult to be established theoretically. And, a mathematic model of ER valve with mesh electrodes plays a vital role in designing its controller. By analyzing the composition elements of an ER valve with mesh electrodes, a semi experimental model was established using the parametric identification toolbox of MATLAB. The consistency between the output of recognition model and the output of validation data reaches 93.46%. Subsequently the PID controller for ER valves with mesh electrodes was designed to meet the operational demands of a 2D matrix display using Simulink. The constrain of simulation was that the pressures of flow channel inlets of ER valves, the dynamic responses of ER valves with mesh electrodes kept stable and within its operational range. The results will be helpful for applications of ER valves with mesh electrodes.

Hydrodynamics and mass transport in an anodic oxidation reactor: Influence of gas evolution and flow path through mesh electrodes

Removal of organic compounds by anodic oxidation requires a sufficiently high rate of mass transport of target compounds to the electrode surface. Since anodic oxidation is often accelerated by the formation of hydroxyl radicals from water oxidation at high anodic potential, the role of oxygen/hydrogen evolution reactions was investigated. Residence time distributions showed that formation of bubbles in zones where fluid velocity was minimal, allowed for strongly improving global hydrodynamics in the reactor. The role of bubbles was also discussed by comparing mass transport coefficients obtained from the limiting current technique to values obtained from kinetics of COD removal during treatment of a model pollutant (phenol). The use of mesh electrodes (with liquid flowing through the electrode) further promoted convection and mass transport of organic compounds compared to plates. However, large bubbles generated at plate electrodes also allowed for convection enhancement in the vicinity of surface of plate electrodes. In both cases, an adverse effect from bubble adhesion was observed because of the decrease in the active surface of electrodes. The mass transport coefficient obtained with the limiting current technique using mesh electrodes was 0.69 10−3 cm/s at 10.8 L/h with a mean velocity of electrolyte past the mesh surface (u¯mesh) of 0.37 cm/s. It decreased to 0.58 10−3 cm/s during the treatment of phenol at the same flow and reached 0.75 10−3 cm/s when increasing the flow to 32.4 L/h. By taking into consideration gas evolution at the surface of electrodes, this study allowed for accurate calibration of an advective – dispersive model with reaction that could be used for sizing such reactors according to the intended application.Abbreviations: Ae, the volumetric surface area (ratio between the geometric volume and the active surface area of the mesh electrodes) (cm−1); CA, aeration by a floor diffuser of fine bubbles and no current at the electrodes; CEP, polarization of the electrodes with a current intensity and no aeration; CW, no electrode polarization and no aeration; COD, chemical oxygen demand (mgO2 L−1);Di, diffusion coefficient of specie i (m2/s); D, dispersion coefficient (cm2 min−1); E(θ), residence time distribution function; EC, electrical energy consumption (kWh gCOD−1);F, Faraday constant (96485C mol−1); HER, hydrogen evolution reaction; IOA, index of agreement;km, mass transport coefficient (m/s); MCE, mineralization current efficiency; ME, model efficiency; OER, oxygen evolution reaction; OH, hydroxyl radical;Ql, liquid flow rate (L/h); rAO: anodic oxidation rate (mol/m−3 s−1); RTD: residence time distribution; ts¯: mean residence time or first moment order; u¯: mean flow velocity (m/s); VT: total volume (L); σ2: variance or second moment order; γ: skewness factor or third moment order; τ: residence time; μ: order moment.

Ultra-Transparent and Multifunctional IZVO Mesh Electrodes for Next-Generation Flexible Optoelectronics

HighlightsUltra-transparent vanadium-doped indium zinc oxide mesh (mIZVO) electrodes are fabricated using a self-cracking template.Fabricated electrodes are employed to realize flexible organic solar cell (OSC), organic light-emitting diode (OLED), and memristor devices. OSC exhibits 14.38% power conversion efficiency and OLED achieves 18.06% external quantum efficiency with mIZVO electrode.Flexible-transparent memristor based on mIZVO mimics various synaptic functions.

Proposing an Affordable Plasma Device for Polymer Surface Modification and Microbial Inactivation.

This study proposes an affordable plasma device that utilizes a parallel-plate dielectric barrier discharge geometry with a metallic mesh electrode, featuring a straightforward 3D-printed design. Powered by a high-voltage supply adapted from a cosmetic plasma device, it operates on atmospheric air, eliminating the need for gas flux. Surface modification of polyethylene treated with this device was characterized and showed that the elemental composition after 15 min of plasma treatment decreased the amount of C to ~80 at% due to the insertion of O (~15 at%). Tested against Candida albicans and Staphylococcus aureus, the device achieved a reduction of over 99% in microbial load with exposure times ranging from 1 to 10 min. Simultaneously, the Vero cell viability remained consistently high, namely between 91% and 96% across exposure times. These results highlight this device's potential for the surface modification of materials and various infection-related applications, boasting affordability and facilitating effective antimicrobial interventions.

Comparison of the effect of different external electrodes on discharge plasma-assisted diffusion flame stabilization

To optimize the design of plasma injectors, the influence of different external electrodes on plasma-assisted flame stabilization was assessed by using a nonequilibrium plasma injector flame control setup. The electrical characteristics of the injector, flame structure parameters, flame intensity, discharge power, and cost-to-effectiveness ratio under different external electrodes (four mesh electrodes and one copper foil electrode) were analyzed using electrical and optical methods. The results show that reducing the mesh size of the external electrode leads to a decrease in breakdown voltage. Compared with a ceramic dielectric barrier-based injector, an injector with a quartz dielectric barrier produces a higher breakdown voltage under the same conditions. For the same actuation voltage, the discharge current increases as the mesh size of the external electrode decreases, and combustion is enhanced by the discharge plasma; therefore, it is better to adopt a smaller mesh hole size to realize good flame stabilization under a lower actuation voltage. However, under the studied working conditions, reducing the mesh hole size of the external electrode increases the cost-to-effectiveness ratio of plasma injector-based flame stabilization. Thus, considering the cost-to-effectiveness ratio and the weight of the injector, an external electrode with a larger mesh hole size should be chosen, which contradicts the above rule.

Modular multilayered PVC gel soft actuators for novel lightweight humanoid facial robot

Electroactive multilayered poly (vinyl chloride) (PVC) gel actuators (MPGAs) have attracted increasing interest in the field of soft robotics. However, they still face problems such as relatively low contraction strain, poor durability, and robustness. Herein, we report a new modular multilayered PVC gel actuator (M-MPGA) based on stainless steel meshed electrodes. The output characteristics of the actuator were notably improved by adjusting the plasticizer content in the gel and optimizing the structural parameters of the meshed anode electrodes. The effect of the number of stacked layers on the performance of the actuator was investigated and a dynamic model was derived for the actuator modular design. Actuator modules with multidirectional degrees of actuation were established and applied to a humanoid facial robot for the first time. The developed actuator with a meshed electrode size of #60 was found to exhibit a high contraction strain of over 20 %, which is almost twice that of the traditional MPGAs with an electrode size of #100. In addition, the fabricated actuator module had a low loss rate (1.152 %), high operating bandwidth (9.7 Hz), fast response (∼45 ms), and exceptional stability (95.24 % retention at 10,000 s actuation) without any distortion of the actuation performance. Furthermore, the developed prototype humanoid facial robot demonstrated the advantages of ultralight weight (754 g), smooth facial expression, and ease of control.

(Invited) Graphene Oxide As an Additive for Ni-Fe Electrodeposition

In contrast to graphene, graphene oxide (GO) is readily disperse in aqueous electrolytes and can be reduced along with nickel and iron metal ions. While others had incorporated graphene in Ni-Fe deposits, no previous studies have addressed the role of GO particles on metal deposition. Ni-Fe is characterized by the anomalous codeposition behavior where there is a tendency of more Fe to be deposited than Ni even though there is an excess of Ni ions in the electrolyte. This behavior has been modeled assuming adsorbed intermediates. Here, the influence of GO on the deposit composition, structure and anomalous codeposition effect is investigated. The deposits were galvanostatically electrodeposited from a boric acid-sulfamate electrolyte at pH 2 containing commercial graphene oxide platelets. Two different cell configurations were examined:1) a rotating cylinder electrode (RCE) and 2) a copper mesh. The rotating cylinder as a working electrode was used in order to investigate mass transport. The copper mesh working electrode was placed in close contact to a flat bottom pH probe in order to examine the local pH change. The addition of GO to the electrolyte had an effect on the deposit composition and the local pH change (Fig 1). The deposit composition had either more Ni or remained the same compared to an electrolyte without GO on the RCE electrode at electrode rotation rates of 372 and 1000 rpm (Fig 1 (a) and (b)). The larger Ni content in the deposit was due to an enhanced Ni partial current density in the presence of GO. The local pH during the deposition on the mesh electrode with vigorous electrolyte stirring increased the local pH (Fig 1(c)). The composition behavior is similar to the results from the RCEs, with higher Ni content in the presence of GO. The local pH increase when GO was present is considered a factor that drives the enhanced Ni content, that may be a consequence of changes in adsorbed hydrogen. GO was not incorporated into the deposit; however, it had a dramatic effect on the morphology. There was less micro-cracks when GO was present in the electrolyte suggesting less adsorbed hydrogen. Thus, GO influenced the adsorbed intermediates making the electrodeposition less anomalous and having less cracks. Acknowledgement: This work was supported in part by the AESF Foundation. Figure 1. The influence of GO in the electrolyte during Ni-Fe electrodeposition (a) composition on a RCE, rotating rate (a) 372, (b)1000 rpm and (c) local pH measurements on a mesh electrode under vigorous stirring, 30 mA/cm2. Figure 1

Design and Preparation at Scale of Ternary NiFe-M-Ox (M=Co, Mo) Catalysts for OER in Alkaline Media

Due to scarcity of Platinum Group Metals (PGMs) widely used in low temperature water electrolysis as cathodes (Hydrogen Evolution Reaction; HER) and anodes (Oxygen Evolution Reaction; OER) a boosting interest to their substitution to Earth abundant elements is observed. It was successfully demonstrated that elements like iron, nickel, cobalt and other (in their oxide and hydroxide forms) can be effective OER catalysts when operate at high pH ranges from 12 to 14 [1-3].This work is devoted to systematic investigation of influence of third element addition to NiFeOx system on a performance and stability of catalysts in alkaline OER. As a co-catalytic elements Mo and Co were selected, based on our previous experience [4,5]. A systematic study on an effect of NiFe-to-M ratio, concentration of precipitation agent and post-treatment temperature were evaluated in a wide range of parameters. Taking into account that mass loading of PGM-free OER catalysts is substantially higher than iridium/ruthenium once and can be up to several milligrams per cm2 all experiments were designed to be scalable. In a laboratory scale reactor, a fascinating batch size of 25g was achieved, using minimal amount of water-based solvents in order to minimize a waste stream generated. Presentation will discuss characterization of obtained materials by SEM, TEM, XPS, XRD and other methods as well as their performance, stability and durability in alkaline conditions, studying Oxygen Evolution Reaction. Acknowledgements and Statements. The authors acknowledge financial support from H2NEW and ElectroCat consortia. References. [1] X. Lyu, J. Li, J. Yang, A. Serov "Significance of Slight Ambient Temperature Variation on the Electrocatalyst Performance toward Oxygen Evolution Reaction" Journal of Environmental Chemical Engineering (2023).[2] X. lyu, A. Serov “Cutting-edge methods for amplifying the oxygen evolution reaction during seawater electrolysis: a brief synopsis” Ind. Chem. Mater., (2023).[3] X. Lyu, Y. Bai, J. Li, R. Tao, J. Yang, A. Serov "Investigation of oxygen evolution reaction with 316 and 304 stainless-steel mesh electrodes in natural seawater electrolysis" J. of Environmental Chemical Engineering 11 (2023) 109667.[4] A. Serov,N. I. Andersen, A. J. Roy, I. Matanovic, K. Artyushkova, P. Atanassov “CuCo2O4 ORR/OER Bi-Functional Catalyst: Influence of Synthetic Approach on Performance”, J. of The Electrochem. Soc. 162 (4) (2015) F449-F454.[5] N. I. Andersen, A. Serov, P. Atanassov “Metal Oxides/CNT Nano-Composite Catalysts for Oxygen Reduction/Oxygen Evolution in Alkaline Media”, Appl. Catal. B: Environmental 163 (2015) 623-627.

Electrochemical CO2 Reduction to Methane with Remarkably High Faradaic Efficiency in the Presence of a Proton Permeable Membrane

The combustion of fossil fuels is a major contributor to rising levels of anthropogenic carbon dioxide (CO2) in the atmosphere. Due to the adverse effects of climate change caused in large part by CO2, new technologies must be developed that contribute to a global renewable energy supply. Electrochemical reduction of CO2 offers a viable pathway to generating value-added products and synthetic fuels to meet our future energy demands while decreasing greenhouse gas emissions. By constructing electrocatalysts capable of modulating proton transfer, we are able to tune product selectivity. Previous studies have demonstrated that two-electron products (CO and HCOOH) can be produced with high selectivity, but multiple-electron transfer products (CH4, CH3OH, and C2+ products) typically are produced at much lower Faradaic efficiencies. In this work, we construct polymer-modified Cu electrodes that exhibit extraordinarily high CH4 production (88% Faradaic efficiency). These electrodes afford a new strategy for increasing the selectivity of CO2 reduction electrocatalysts, an attribute that is key in developing industrially-relevant CO2 conversion devices. Nafion is a widely used fluoropolymer that is often mixed with electrocatalysts to facilitate proton transport. In contrast to these Nafion-catalyst composites, this work studies electrodes covered by Nafion overlayers for the CO2 reduction reaction. By varying the thickness, substrates, and voltage, we perform a detailed study of the effect of Nafion overlayers on metal and carbon mesh electrodes for CO2 reduction. Depending on the thickness of the Nafion membrane, CO2 reduction occurs at either the polymer–electrolyte interface or electrode–polymer interface. A Nafion overlayer of 15 μm on a Cu electrode enables an extraordinarily high yield of CH4 production (88% Faradaic efficiency) at a low overpotential (540 mV) via the stabilization of metal-bound CO intermediates. To the best of our knowledge, this yield is the highest for electrocatalytic CO2 reduction to CH4 production at room temperature reported.

The plausibility and ideal design of electrochemical disinfection for drinking water in hospital susceptible to Legionella and E. coli contamination, compared to traditional methods

Legionella and Escherichia coli (E. coli), bacteria lethal to humans, are widespread in drinking water. Traditional disinfection methods using chlorine gas, temperature control, and ultraviolet are widely applied today but have several drawbacks. In contrast, the electrochemical disinfection methods could address the problems. This study reviews the literature on electrochemical disinfection and compares traditional disinfection methods with electrochemical ones under evaluation of cost, E. coli contamination efficiency, and effect. Results show that titanium meshed electrodes are the most cost-efficient compared to more effective electrodes with significantly higher production costs. The application of the proposed electrochemical disinfection device gains a financial advantage over traditional methods, suggesting a promising future for the disinfection method. Meanwhile, investigations on the electrocoagulation method aim to disinfect the water to the drinking water level. Results show that the combination of electrocoagulation and the titanium meshed electrode device proves to have a better disinfection effect than individual methods and a lower cost than traditional methods. This research provides insight into the properties of biofilms, traditional disinfection methods, and different electrochemical disinfection methods. After reviewing the literature and evaluating various factors, we offer an ideal design for Legionella and E. coli-contaminated water disinfection devices with a promising future once applied.

Tackling Challenges of Long-Term Electrode Stability in Electrochemical Treatment of 1,4-Dioxane in Groundwater.

Electrochemical advanced oxidation is an appealing point-of-use groundwater treatment option for removing pollutants such as 1,4-dioxane, which is difficult to remove by using conventional separation-based techniques. This study addresses a critical challenge in employing electrochemical cells in practical groundwater treatment─electrode stability over long-term operation. This study aims to simulate realistic environmental scenarios by significantly extending the experimental time scale, testing a flow-through cell in addition to a batch reactor, and employing an electrolyte with a conductivity equivalent to that of groundwater. We first constructed a robust titanium suboxide nanotube mesh electrode that is utilized as both anode and cathode. We then implemented a pulsed electrolysis strategy in which reactive oxygen species are generated during the anodic cycle, and the electrode is regenerated during the cathodic cycle. Under optimized conditions, single-pass treatment through the cell (effective area: 2 cm2) achieved a remarkable 65-70% removal efficiency for 1,4-dioxane in the synthetic groundwater for over 100 h continuous operation at a low current density of 5 mA cm-2 and a water flux of 6 L m-2 h-1. The electrochemical cell and pulse treatment scheme developed in this study presents a critical advancement toward practical groundwater treatment technology.

Electrode switch-an efficient induced approach for self-activation of an electrode toward water splitting.

In this paper, we provide a novel electrode switch (ES) method to improve the stability of the alkaline electrolyzer toward water splitting. The voltage of the alkaline electrolyzer consisting of commercial Ni mesh electrodes utilizing the ES mode exhibits extreme stability because highly active Ni oxide(hydroxide) with oxygen defects is in situ formed during the hydrogen evolution reaction (HER) polarization process.

Carbon Nanotube-Doped 3D-Printed Silicone Electrode for Manufacturing Multilayer Porous Plasticized Polyvinyl Chloride Gel Artificial Muscles.

Plasticized polyvinyl chloride (PVC) gel has large deformation under an applied external electrical field and high driving stability in air and is a candidate artificial muscle material for manufacturing a flexible actuator. A porous PVC gel actuator consists of a mesh positive pole, a planar negative pole, and a PVC gel core layer. The current casting method is only suitable for manufacturing simple 2D structures, and it is difficult to produce multilayer porous structures. This study investigated the feasibility of a 3D-printed carbon nanotube-doped silicone electrode for manufacturing multilayer porous PVC gel artificial muscle. Carbon nanotube-doped silicone (CNT-PDMS) composite inks were developed for printing electrode layers of PVC gel artificial muscles. The parameters for the printing plane and mesh electrodes were explored theoretically and experimentally. We produced a CNT-PDMS electrode and PVC gel via integrated printing to manufacture multilayer porous PVC artificial muscle and verified its good performance.

Characterization of Transparent Electrodes with Ag Metal-mesh using MATLAB

It is well-known that optical transparence and electric resistance have a trade-off relationship in transparent electrodes. For this reason, developing methods to predict this relation have been important in various fields of academic research as well as for industrial applications. Herein, we suggest a simple method which reveals the relationship between optical transparence and electric resistance using MATLAB, based on the geometric characteristics of a random metal network. Ag metal-mesh transparent electrodes were fabricated with various conditions using colloidal silica cracked-templates and a Radio Frequency (RF) sputtering system. MATLAB software was used to analyze structural images of the Ag mesh network, automatically quantifying the density and width of the Ag meshes. From these data, the transparency and sheet resistance values of the Ag mesh electrodes were predicted and compared with measured values. Regarding transparency, the introduction of fitting parameters revealed minimal differences between the experimental and predicted values obtained from the structure images. Although the predicted sheet resistance was slightly different than the real measured values due to atomic defects or imperfections in the crystals of the Ag-mesh network, it was possible to observe a similar trend between the measured and predicted sheet resistances with changes in the fractional coverage area of the Ag-mesh network.

Hydrothermal synthesized nickel tungstate (NiWO4) microflowers for supercapacitor and water-splitting

Herein, we have synthesized nickel tungstate microflowers (NWO MFs) using the hydrothermal route and used them as an electrode in electrochemical and electrocatalytic applications. In this article, we discuss the effects of the concentration of surfactant on the NWO MFs. Additionally, the resultant products are undergone to assess the energy storage and water-splitting phenomena. In addition, NWO-SM (steel mesh) electrode demonstrates the maximum specific capacitance (Cg) and specific capacity (Csp) of 712 F/g and 158 mAh/g at 5 mV/s with ∼95% capacitive retention over the 5000 cycles. Furthermore, the fabricated device reveals the maximum performance of the capacitance and capacity of 185 F/g and 75 mAh/g at 5 mV/s and 160 F/g and 53 mAh/g with the highest energy (Ed) and power densities (Pd) of 24 Wh/kg and 1600 W/kg at 5 mA/cm2 respectively. The hybrid device shows better capacitive properties with excellent stability (94% over 5000 cycles). The NWO-SM electrodes were tested for electrocatalytic activities using different techniques. The NWO-1 SM electrode exhibited strong electrocatalytic activity with a moderate overpotential value of 302 mV, a negligible Tafel slope (118 mV/dec), an acceptable electrochemical surface area (ECSA) value of 121 cm2, and exceptional stability over 10 hours.

Ultrafast Spectroelectrochemistry of the Catechol/o‐Quinone Redox Couple in Aqueous Buffer Solution

AbstractEumelanin is a natural pigment found in many organisms that provides photoprotection from harmful UV radiation. As a redox‐active biopolymer, the structure of eumelanin is thought to contain different redox states of quinone, including catechol subunits. To further explore the excited state properties of eumelanin, we have investigated the catechol/o‐quinone redox couple by spectroelectrochemical means, in a pH 7.4 aqueous buffered solution, and using a boron doped diamond mesh electrode. At pH 7.4, the two proton, two electron oxidation of catechol is promoted, which facilitates continuous formation of the unstable o‐quinone product in solution. Ultrafast transient absorption (femtosecond to nanosecond) measurements of o‐quinone species involve initial formation of an excited singlet state followed by triplet state formation within 24 ps. In contrast, catechol in aqueous buffer leads to formation of the semiquinone radical Δt>500 ps. Our results demonstrate the rich photochemistry of the catechol/o‐quinone redox couple and provides further insight into the excited state processes of these key building blocks of eumelanin.

Hierarchical mesh-type oxygen electrode using carbon nanotube framework for anion-exchange membrane-based unitized regenerative fuel cells

Developing three-dimensional porous oxygen electrodes (OE) is crucial for enhancing round-trip efficiency (RTE) of anion-exchange membrane-based unitized regenerative fuel cells (AEM_URFCs). Herein, a novel OE design of AEM_URFCs is presented based on a hierarchical mesh electrode (HME) with a porous carbon nanotube (CNT) framework. The HME, featuring square-shaped macropores achieved by dispersing catalyst nanoparticles on the CNT framework enhances surface area, mass transport, and electron transport. Half-cell test demonstrated superior oxygen reduction reaction and oxygen evolution reaction activity compared to conventional electrodes. Moreover, the HME maintained stable ORR and OER activity during the stability test. In single-cell tests, the AEM_URFCs with the HME exhibited higher RTE (55% at 20 mA cm−2), surpassing the conventional electrode (52%). Furthermore, RTE was maintained at a remarkable 41% under ultrahigh current density (250 mA cm−2), which is unprecedented in the literature. The AEM_URFCs featuring the HME displayed superior cyclability over 5 cycles and durable performances under both fuel cell and water electrolysis modes.

Self-Powered Autonomous Electrostatic Dust Removal for Solar Panels by an Electret Generator.

Solar panels often suffer from dust accumulation, significantly reducing their output, especially in desert regions where many of the world's largest solar plants are located. Here, an autonomous dust removal system for solar panels, powered by a wind-driven rotary electret generator is proposed. The generator applies a high voltage between one solar panel's output electrode and an upper mesh electrode to generate a strong electrostatic field. It is discovered that dust particles on the insulative glass cover of the panel can be charged under the high electrical field, assisted by adsorbed water, even in low-humidity environments. The charged particles are subsequently repelled from the solar panel with the significant Coulomb force. Two panels covered with sand dust are cleaned in only 6.6min by a 15cm diameter rotary electret generator at 1.6ms-1 wind speed. Experimental results manifest that the system can work effectively in a wide range of environmental conditions, and doesn't impact the panel performance for long-term operation. This autonomous system, with its high dust removal efficiency, simplicity, and low cost, holds great potential in practical applications.