Specific Surface Conductivity Research Articles

Enhancement in capacitive performance of Co3O4 with MnTiO3 via composite (MnTiO3/Co3O4) strategy developed by ultrasonication route

The specific surface area, conductivity and cyclic stability of nanomaterials significantly impact a pseudocapacitor electrode's performance. The Co3O4 is economically viable and widely available but has limited surface area and conductivity. However, MnTiO3 has a greater surface area and exhibits superior ion conductivity, resulting in better specific capacitance (Cs). Herein, a novel MnTiO3/Co3O4 nanocomposite is manufactured to enhance the properties of Co3O4 using an ultrasonication technique for application in supercapacitors. Several analytical methods were utilized to examine synthesized materials' textural, structural and morphological characteristics. The MnTiO3/Co3O4 nanocomposite demonstrated notable Cs of 1534.67 F/g, specific energy (SE, 64.05 Wh/kg) and specific power (SP, 274.1 W/kg) at current density (Cd) of 1 A/g in 2.0 M KOH solution, according to electrochemical experiments. Additionally, after 5000th cycles, the nanocomposite exhibits excellent cyclic stability than pristine materials. This study not only showcases the significant capabilities of the commercially accessible MnTiO3/Co3O4 nanocomposite but also presents a novel approach for developing cost-effective, high-performing composite materials with multiple potential applications in the energy field.

Carbon quantum dots modified and Y3+ doped Ni3 (NO3 )2 (OH)4 nanospheres with excellent battery-like supercapacitor performance.

Supercapacitor is an important energy storage device widely used in the automobile industry, military production, and communication equipment because of its fast charge-discharge rate, and high power density. Herein, carbon quantum dots modified and Y3+ doped Ni3 (NO3 )2 (OH)4 (NiY@CQDs) nanospheres are prepared by a solvothermal method and used as an electrode material. The electrochemical properties of NiY@CQDs were measured in a three-electrode system. An asymmetric supercapacitor (ASC) cell was assembled with activated carbon (AC) as the anode and NiY@CQDs as the cathode. The electrochemical properties of the ASC device were measured in a two-electrode system. Experimental results show the shape of NiY@CQDs is petal-shaped and the introducing carbon quantum dots and doping Y3+ significantly increases the specific surface area, conductivity, and specific capacitance of Ni3 (NO3 )2 (OH)4 . The mass-specific capacitance of NiY@CQDs reaches up to 2944 F g-1 at a current density of 1 A g-1 . The asymmetric supercapacitor of NiY@CQDs//AC has a high energy density of 138.65 Wh kg-1 at a power density of 1500 W kg-1 , displaying a wide range of application prospects in the energy storage area.

Boron, oxygen co-doped porous carbon derived from waste tires with enhanced hydrophilic interface as sustainably high-performance material for supercapacitors

The number of scrap tires has been increasing in recent years and pyrolytic carbon black (CBp) is an important product of scrap tire pyrolysis. However, due to the poor surface activity and the high contents of ash and carbonaceous deposits, the untreated CBp can only be used for low-end rubber products with poor economic efficiency. Herein, we propose a new Boron, Oxygen co-doped porous carbon (AB-CBp) through a facile KOH activation and boric acid modificating CBp. The modification of boron and oxygen heteroatoms has dramatically increased its specific surface area (SSA), hydrophilicity and conductivity, leading to the enhanced specific capacitance and rate performance. The assembled zinc-ion hybrid super-capacitor (ZIHC) devices have a maximum capacity of 83.2 mAh g−1 at 0.1 A g−1. Moreover, this device demonstrates an impressive cycling life with a high capacitance retention rate of 92.3 % at 10 A g−1 after 30,000 cycles. The work not only paves a new way for the efficient utilization of CBp from waste tires, but also demonstrates the employments of inexpensive and sustainable material for the further development of energy storage.

Stability of Ti3C2Tx MXenes in engineered environments

MXenes are a newer class of 2D materials with desirable properties, making them attractive for various environmental applications, including remediation and as membranes for water treatment.

A comprehensive study on effect of carbon nanomaterials as conductive additives in EDLCs

This study performs a comprehensive investigation to objectively analyze the effects of various carbon nanomaterials using as conductive additives (5 wt%) in activated carbon (AC) based electrodes for electrical double-layer capacitors (EDLCs). A variety of carbon nanomaterials including carbon black (CB), single-walled carbon nanotubes (SWCNT), graphene nanoplatelets (GNP), fullerenes (C60), and activated carbon nanofibers (ACNF) are considered in this work as they provide a diverse combination of intrinsic properties such as specific surface area, conductivity, micro-mesoporous structures, and geometry of nanomaterials. These additives are incorporated into freestanding carbon electrodes, and their EDLC performance in a neutral aqueous electrolyte is investigated by means of electrochemical measurements. The findings from this work provide useful insight into how the properties of various carbon nanomaterials influence EDLC performance in different aspects such as capacitive behavior, resistivity, performance at different current densities, charge propagation properties, and stability over long-term cycling. The results show that each carbon additive has its own strengths and limitations for different performance parameters considered. The unfavorable material properties of C60 cause a significant decrease in capacitance at high current density, leading to the lowest device performance incorporated with C60 as additives. While GNP and SWCNT show high crystallinity, low ID/IG ratios, the EDLCs still exhibit decreased specific capacitance and moderate energy densities due to their relatively limited specific surface area and high resistivity of the resultant composite electrodes compared to the pristine AC. The CB additives-based samples demonstrate the highest conductivity of dry electrodes and low equivalent series resistance (ESR) in EDLCs. On the other hand, a reduction in capacitance at high current densities and material degradation during long-term cycling are observed for CB samples, which could be attributed to the high dispersibility of CB causing limited interparticle voids and thus increasing diffusion resistance. In contrast, the use of ACNFs significantly reduces the diffusion resistance and improves the cyclic stability compared with CB based samples due to the advantages of larger specific surface area and superior micro-mesoporous structures of ACNFs. In particular, EDLCs with ACNFs demonstrate an increase in specific capacitance and energy density by 99 % and 76 %, respectively compared to CB based EDLCs at a current density of 20 A/g. This work elucidates the complex interplay between carbon nanomaterials using as additives and corresponding EDLC performance. These results provide important information to the community for future development of new energy conversion and storage devices.

Upcycling spent graphite in LIBs into battery-grade graphene: Managing the produced waste and environmental impacts analysis

This study focuses on connecting graphite demand to battery materials demand, providing a solution to the identified shortage of battery materials and promoting sustainable development. This research used modified Hummer's method to synthesize graphene from the recycled graphite and compared it with graphene synthesized from purified recycled graphite. The purification of recycled graphite was implemented by acid curing-leaching and calcination. The analysis showed that the reduction reaction effectively removed oxygen-containing functional groups from the graphene, resulting in enhanced quality of the produced graphene. Hummer’s waste acid was used as a leaching reagent for different LIBs’ cathode types in waste management. The waste acid was found to be a strong reagent for transition metals leaching and obtained almost full recoveries of Li, Co, Mn, and Ni from spent LIB cathodes. The synthesized graphene exhibited higher specific surface areas and conductivity values compared to battery-grade graphite. The electrochemical performance of the graphene sheets in lithium half-cells was evaluated, and it was found that the graphene synthesized from recycled graphite enabled increased lithium insertion at active sites, suggesting its potential for enhanced lithium retention. Furthermore, a life cycle assessment study was conducted to evaluate the environmental impacts of the recycling and synthesis processes. This study demonstrates the potential of recycling graphite from spent battery anodes to produce high-quality graphene with improved electrochemical properties.

Locally graphitized biomass-derived porous carbon nanosheets with encapsulated Fe3O4 nanoparticles for supercapacitor applications

Waste biomass-derived porous carbons offer significant application prospects, especially in the field of carbon-based supercapacitors, while simultaneously reducing carbon emissions. However, their relatively low conductivity and charge storage capacity have resulted in a low energy density for supercapacitor applications, thereby significantly impeding their large-scale commercial application. At present, comprehensively enhancing the performance of biomass-derived carbon-based supercapacitors (BC-SCs), including energy density, power density, cyclic stability, and rate capability, remains a challenge. To overcome this challenge, Fe3O4 nanoparticles with high conductivity are successfully encapsulated within biomass-derived carbon nanosheets. In conjunction with a localized graphitization strategy, a novel electrode material, locally graphitized biomass-derived hierarchical porous carbon nanosheets with encapsulated Fe3O4 nanoparticles, possessing high specific surface area and conductivity, is successfully prepared. Coupled with TFA electrolyte featuring a high working voltage of 1.4 V, a significant enhancement in the energy density is achieved for BC-SCs, along with ultra-long cyclic durability and excellent fast-charging capabilities. The BC-SCs assembled achieves a high energy density of 15.80 kW kg−1 at a power density of 483 W kg−1. Even at a high power density of 16.40 kW kg−1, the energy density remains at 11.4 Wh kg−1. After 100,000 cycles, the capacitance retention remains remarkably high at 99.6 %. By utilizing hydroquinone as a redox additive, the energy density can be further improved to 32.0 Wh kg−1. This work would pave the way for the large-scale commercialization of BC-SCs.

N, O, P-doped porous carbon with high surface utilization and long cycling life for supercapacitors

The development of miniaturized and lightweight supercapacitors (SCs) becomes a hot research region. Improving the surface area utilization of porous carbon materials can effectively promote the energy density and power density of SCs. This work first constructs three-dimensional porous poly(p-phenylenediamine) hydrogel through adding phytic acid. Thereafter, N, O, P-doped porous carbon (NOPPC) was obtained via simple one-step pyrolysis treatment. The unique three-dimensional porous structure of NOPPC inherited from poly(p-phenylenediamine) hydrogel provides plentiful ion storage space and ion transportation channels. Heteroatom-doped feature endows NOPPC with good wettability and more active surface area. The surface utilization of NOPPC-800 reaches up to 2.56 F m−2, which is better than many carbon materials in literatures. NOPPC-800 can still maintain 135 F g−1 at 20 A g−1. The capacity retention ratio of NOPPC-800 can reach up to 93.4 % after 10000 cycles at 10 A g−1. The quantitative analysis of energy storage mechanism of NOPPC illustrates the synergistic impact of pore structure and doped heteroatoms. These electrochemical results show that NOPPC possesses good practical application value. NOPPC-800//NOPPC-800 supercapacitor shows high energy density and excellent cycle stability. The results show that the balance of heteroatom content, specific surface area and conductivity is the key to obtain promising carbon electrode materials and can be realized via tuning carbonization temperature. This work also demonstrates that rational structure control of carbon precursor is the effective way to promote the capacity of carbon materials.

A wood pulp sponge cleaning wipe as a high-performance bioanode material in microbial electrochemical systems for its vast biomass carrying capacity, large capacitance, and small charge transfer resistance

Microbial electrochemical systems are a promising green and sustainable technology that can transform waste into electricity. Improving conversion efficiency and lowering system costs, particularly for electrodes, are the primary directions that promote practical application. Cellulose sponges made from wood pulp have been industrially mass-produced in various application scenarios due to their porosity and green sustainability. In this study, the three-dimensional (3D) porous cellulose sponges carbon (CSC) was obtained by directly carbonizing cellulose sponges at different temperatures (600, 700, 800, 900, 1000, and 1100 °C). It has been successfully used as a high-performance anode in microbial fuel cells (MFCs). The carbonization temperature significantly impacted the materials’ specific surface area, conductivity, and capacitance. The greater the anode material's carbonization temperature, the lower the charge transfer resistance and the higher the maximum power density (CSC-1100, 4.1 ± 0.1 W m–2). The CSC-700′s maximum power density (3.62 ± 0.11 W m–2) was the highest power density reported to date among lignocellulose-based anodes with relatively low energy consumption. The pleated multilayer porous surface promotes microbial adhesion and can build thicker biofilms with the highest biomass of 2661 ± 117 μg cm–2 (CSC-1100) and containing 86 % electrogenic bacteria (Geobacter). To investigate the effect of conducting polymers on the material's surface, we introduced polyaniline and polypyrrole. We found that the CSC-1000/PPy bioanodes produced a maximum power density (4.18 ± 0.05 W m–2), slightly higher than of without polypyrrole-modified (CSC-1000, 3.99 ± 0.06 W m–2), indicating that the CSCs anode surface had excellent electron transfer efficiency and could achieve the same amount of energy as the polypyrrole surface. This study introduced a promising method for fabricating high-performance anodes using low-cost, industrialized, and sustainable materials.

RecJf exonuclease-catalyzed signal amplified aptasensor for sensitive detection of atrazine using Ni6MnO8@C/Au nanorods and COF@MOF nanohybrids

Atrazine (ATZ) represents an endocrine-disrupting pesticide posing significant threats to both the environment and human well-being. In this study, a novel turn-on electrochemical aptasensor was successfully developed for highly sensitive ATZ detection. It relied on Ni6MnO8@C/Au nanorods (Ni6MnO8@C/AuNR) and covalent-metal organic framework nanohybrids (MCA@Ce-MOF) with RecJf-catalyzed target recycling amplification. Notably, this marks the first instance of utilizing this strategy for ATZ detection. The substrate material, ultrathin Ni6MnO8@C/AuNR nanosheets, enhanced the specific surface area, conductivity, and biocompatibility, thereby facilitating biomolecule attachment and improving sensitivity. The scaffolds, hierarchically porous MCA@Ce-MOF, not only elevated the loading efficiency and surface concentration of signal molecules, but also strengthened the binding firmness of biomolecules. RecJf-catalyzed target recycling was triggered in the presence of ATZ, further magnifying electrochemical signals. Leveraging these unique attributes, the developed aptasensor exhibited exceptional ATZ detection performance with a low detection limit of 4.9 fg·mL−1, a wide linear range of 4 × 10−5–4 ng·mL−1, and a satisfactory recovery of 93.3–99.6% in corn samples. With its diverse signal amplification capabilities, this aptasensor holds promise for detecting various analytes in environmental monitoring applications.

MXene-Induced Flexible, Water-Retention, Semi-Interpenetrating Network Hydrogel for Ultra-Stable Strain Sensors with Real-Time Gesture Recognition.

As water-saturated polymer networks, hydrogels are a growing family of soft materials that have recently become promising candidates for flexible electronics application. However, it remains still difficult for hydrogel-based strain sensors to achieve the organic unity of mechanical properties, electrical conductivity, and water retention. To address this challenge, based on the template, the excellent properties of MXene nanoflakes (rich surface functional groups, high specific surface area, hydrophilicity, and conductivity) are fully utilized in this study to prepare the P(AA-co-AM)/MXene@PDADMAC semi-interpenetrating network (semi-IPN) hydrogel. The proposed hydrogel continues to exhibit excellent strain response and flexibility after 30 days of storage at room temperature, and its performance do not decrease after 1100 cycles. Considering these characteristics, a hydrogel-based device for converting sign language into Chinese characters is successfully developed and optimized using machine learning. Therefore, this study provides novel insight and application directions for hydrogel families.

Optimized Graphene Hydrogels for Electrochemical Applications from High-Concentration GO/Gnp Dispersions

As the world combats climate change, energy storage solutions will be required to bridge the gap between the supply and demand of renewable energy sources. Supercapacitors have a higher power density and cyclic stability than batteries, making them more useful for selected applications. These devices utilize high surface area electrode materials, such as graphene, with enough active sites for sufficient ion adsorption to occur. Graphene hydrogels self-assemble via the hydrothermal reduction of graphene oxide (GO) dispersions. These three-dimensional structures have high specific surface areas while avoiding the use of binders. Binders usually negatively impact the conductivity of the material and require the use of conductive additives which lower specific performance data. As such, graphene hydrogels are attractive as a supercapacitor electrode material.Recently, graphene nanoplatelet (GNP) dispersions stabilized by small amounts of GO were used to form more cost-effective and better-performing hydrogels. Though GO/GNP hydrogels are a suitable alternative to those formed from dispersions of GO, the formulation of this material has yet to be optimized. In this work, we investigate the formation of GO/GNP hydrogels by assessing the influence of several input parameters on the specific surface area and mechanical stability of the hydrogel structure. A set of experiments based on a design of experiments is used. Based on the results, an optimized hydrogel is formed and characterized. Compared to typical hydrogels formed from dispersions of GO, the optimized GO/GNP hydrogel leads to significant improvements in both the specific surface area and conductivity of the material. When used in a supercapacitor, low internal resistance and high stability are observed while volumetric capacitance is increased by up to over 400%.

A novel and sensitive dual signaling ratiometric electrochemical aptasensor based on nanoporous gold for determination of Ochratoxin A

Ochratoxin A (OTA) is a toxic pollutant in foods, and its actual detection is crucial. A novel and sensitive dual signaling ratiometric electrochemical aptasensor based on nanoporous gold (NPG) was proposed to determine OTA. NPG, with high specific surface area and conductivity, improved the sensitivity by immobilizing more aptamers. Meanwhile, the dual signaling ratiometric strategy improved the detection reproducibility through self-referencing and built-in correction. NPG and ratiometric strategy multi-amplified the dual signal changes. The sensitivity of OTA was evaluated by the ratio of methylene to ferrocene current values. Under the optimal conditions, the NPG-based aptasensor demonstrated excellent sensitivity with a wide linear range of 1 pg/mL to 2 ng/mL and the limit of detection (LOD) of 0.4 pg/mL for OTA. This developed aptasensor also effectively detected OTA in spiked Cordyceps sinensis and grape juice samples, with recovery values falling in the 98.49–108.0% range.

Electrochemical Determination of Acetaminophen with a FeNi Nanoparticle Reduced Graphene Oxide (rGO) Nanocomposite and Differential Pulse Voltammetry (DPV)

Acetaminophen (AP) is one of the most commonly used antipyretics. Accurate and efficient determination of its concentration is of great significance to human health. In this work, FeNi alloy nanoparticles and reduced graphene oxide (rGO) were compounded by an ultrasonic method to obtain FeNi/rGO nanocomposites. The nanocomposites were analyzed by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), and cyclic voltammetry (CV). Due to the catalytic activity of FeNi alloy nanoparticles and the synergy between the high specific surface area and conductivity of reduced graphene oxice (rGO), a FeNi/rGO nanocomposite showed excellent electrocatalysis for acetaminophen determination. With differential pulse voltammetry (DPV) as the analytical method, the linear range for acetaminophen is from 1 to 100 and 100 to 3,000 μM with a limit of detection (LOD) equal to 0.3 μM. Moreover, the sensor also has good reproducibility and selectivity with high recoveries in practical analysis.

Conductivity of carbonized and activated leather waste

The conductivity of chromium-tanned pigskin leather waste carbonized in various manner to nitrogen-containing carbons is reported. Four protocols have been tested: (1) The simple carbonization at 800 °C in inert atmosphere, (2) the carbonization at 500 °C followed by the activation with potassium hydroxide at 800 °C, (3) direct activation with the alkali at 800 °C and (4) the similar activation with potassium hydroxide excess. The fibrous collagen morphology was preserved after the carbonization except for some shrinkage. The yield in the simple carbonization, 26.9 wt%, was reduced to 23.9 wt% for the activated products. Elemental analysis indicated reduced content of organic elements after carbonization, and X-ray fluorescence the composition of growing inorganic part. The chromium content in biochar was close to 12 wt% and the X-ray diffraction revealed also the presence of metallic chromium in addition to expected chromium(III) oxide and sulfide. FTIR and Raman spectroscopies demonstrated the typical pattern of carbonized materials. The specific surface area and pore volume increased after the activation. The resistivity of the powdered carbonized leather was determined in four-point van der Pauw setup. It decreased by more than one order of magnitude as applied pressure increased from 0.1 to 10 MPa. The sample conductivity depended only a little on the way of carbonization and was of the order of tenths to units S cm−1 at 10 MPa. The precarbonization followed by the activation provided the best result with respect to the yield, nitrogen-content, specific surface area and conductivity of the carbonized material.

Electrochemical behavior of GNP/CNT porous composite for supercapacitor

Herein, we systematically demonstrate the synergistic behavior of GNP/CNT composite as an electrode material. Uniform dispersion of CNTs effectively inhibits the restacking of GNP sheets, resulting in enhanced specific surface area, porosity, and conductivity. Moreover, CNT intercalation provides a porous and interconnected network for electrolyte ion transportation. As a result, GNP composite having 1.0 wt% multi-walled carbon nanotube (MWCNTs) shows specific capacitance up to 143 Fg−1 at 5 mVs−1, an improvement of 150% compared to pristine GNPs. The improved electrochemical performance implies that the proposed composite electrode is a promising candidate for supercapacitor application.

Investigation of electrical conductivity based on porous hollow carbon black for EDLC

The crystallinity of carbon black nanoparticles is inhomogeneous, and therefore hollow type carbon black are prepared by selectively removing amorphous cores while maintaining aligned skins. Herein, we prepare hollow carbon nanoparticles composed of mesopores with good EDLC performance from commercial carbon black through an extremely mild oxidation method. Hollow type carbon black have improved specific surface area and an ion reservoir region can be formed due to their structural characteristics, making them suitable for EDLC electrodes. Carbon blacks, however, has different physical properties such as the specific surface and electrical conductivity. Exploiting these differences, we investigated the effect of surface area and electrical conductivity on EDLC performance.

A Highly Conductive and Supercapacitive MXene/N-CNT Electrode Material Derived from a MXene-Co-Melamine Precursor

MXene is a two-dimensional nanostructured transition metal carbon/nitride and carbon nanotubes (CNTs) are a one-dimensional graphitized carbon material, which are widely exploited for their large specific surface and excellent electrical conductivity, but the easy aggregation limits their performance. In this work, a MXene-Co-melamine precursor is elaborately assembled by coordination bonds and a highly dispersed MXene/N-CNT composite material is ultimately constructed via a segmental pyrolysis of the MXene-Co-melamine precursor. This strategy synchronously relieves the self-restacking problem of MXene and N-CNTs. The optimal 0.60-MXene/N-CNT is composed of abundant and homogeneous CNTs with a high nitrogen dosage of 5.879 wt %. And it has a large BJH adsorption average pore size of 11.5 nm, a high microporous–mesoporous distribution of 1.94% micropores and 61.67% mesopores, and a well-matched hierarchical pore structure. Due to the orderly assembled porous structure of MXene and N-CNTs, the 0.60-MXene/N-CNT exhibits a high specific capacitance of 167.2 F g–1 at 0.5 A g–1. The assembled 0.60-MXene/N-CNT//AC asymmetric supercapacitor maintains a high capacitance retention of 73.2% after 10,000 cycles at 5 A g–1 current density and a high Coulomb efficiency of 97.5%. Its energy density also can reach 12.1 Wh kg–1 at a power density of 195.4 W kg–1.

Fe Powder Catalytically Synthesized C3N3 toward High-Performance Anode Materials of Lithium-Ion Batteries

Recently, carbon nitrides and their carbon-based derivatives have been widely studied as anode materials of lithium-ion batteries due to their graphite-like structure and abundant nitrogen active sites. In this paper, a layered carbon nitride material C3N3 consisting of triazine rings with an ultrahigh theoretical specific capacity was designed and synthesized by an innovative method based on Fe powder-catalyzed carbon-carbon coupling polymerization of cyanuric chloride at 260 °C, with reference to the Ullmann reaction. The structural characterizations indicated that the as-synthesized material had a C/N ratio close to 1:1 and a layered structure and only contained one type of nitrogen, suggesting the successful synthesis of C3N3. When used as a lithium-ion battery anode, the C3N3 material showed a high reversible specific capacity up to 842.39 mAh g-1 at 0.1 A g-1, good rate capability, and excellent cycling stability attributed to abundant pyridine nitrogen active sites, large specific surface area, and good structure stability. Ex situ XPS results indicated that Li+ storage relies on the reversible transformation of -C=N- and -C-N- groups as well as the formation of bridge-connected -C=C- bonds. To further optimize the performance, the reaction temperature was further increased to synthesize a series of C3N3 derivatives for the enhanced specific surface area and conductivity. The resulting derivative prepared at 550 °C showed the best electrochemical performance, with an initial specific capacity close to 900 mAh g-1 at 0.1 A g-1 and good cycling stability (94.3% capacity retention after 500 cycles at 1 A g-1). This work will undoubtedly inspire the further study of high-capacity carbon nitride-based electrode materials for energy storage.

Oxygen vacancies-rich Cu-W18O49 nanorods supported on reduced graphene oxide for electrochemical reduction of N2 to NH3

High-performance nitrogen fixation is severely limited by the efficiency and selectivity of a catalyst of electrochemical nitrogen reduction reaction (NRR) under ambient conditions. Here, the RGO/WOCu (reduced graphene oxide and Cu-doping W18O49) composite catalysts with abundant oxygen vacancies are prepared by the hydrothermal method. The obtained RGO/WOCu achieves an enhanced NRR performance (NH3 yield rate:11.4 μg h−1 mgcat-1, Faradaic efficiency: 4.4%) at −0.6 V (vs. RHE) in 0.1 mol L-1 Na2SO4 solution. Furthermore, the NRR performance of the RGO/WOCu still keeps at 95% after four cycles, demonstrating its excellent stability. The Cu+-doping increases the concentration of oxygen vacancies, which is conducive to the adsorption and activation of N2. Meanwhile, the introduction of RGO further improves the electrical conductivity and reaction kinetics of the RGO/WOCu due to the high specific surface area and conductivity. This work provides a simple and effective method for efficient electrochemical reduction ofN2.