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The quest for high-performance OER electrocatalysts has been a focal point in the field of energy conversion and storage. Despite the promise shown by nickel sulfide-based materials, the enhancement of their catalytic activity through singular strategies has been found to be inadequate for achieving the desired comprehensive performance improvements. In this context, we introduce a novel V-doped FeO/NiS nanosheet array (V-FeO/NiS/NF) synthesized through a synergistic approach involving heteroatom doping and heterostructure engineering. This advanced material exhibits structural integrity, a three-dimensional nanosheet morphology, and superior electrical conductivity, which collectively contribute to its exceptional electrochemical performance. The V-FeO/NiS/NF electrode can reach a current density of 10 mA cm−2 with an impressively low overpotential of 213 mV and sustains its activity for an extended period of 196 hours, surpassing the stability and efficiency of many electrodes. Theoretical insights reveal that vanadium doping significantly lowers the adsorption free energy of key reaction intermediates, thereby facilitating the OER process. This study not only presents a robust and efficient OER electrocatalyst but also paves the way for the design of advanced, cost-effective nickel-based sulfide catalysts through strategic heteroatom incorporation and structural optimization. [Display omitted] • Self-assembled 3D nanosheets of V-FeO/NiS were successfully prepared. • It exhibited excellent OER electrocatalytic performance with an overpotential of 213 mV at 10 mA cm-2 and also have outstanding stability for 196 h. • DFT indicate that V doping is beneficial to reduce the free energy of adsorption of oxygen-containing intermediates. [ABSTRACT FROM AUTHOR]

The high-energy-density lithium-sulfur (Li-S) batteries (2600 Wh kg−1) are seriously hampered by the slow redox reaction kinetics and obnoxious shuttle effects of sulfur cathode. Introducing a catalytic host to promote sulfur redox kinetics is a promising way to inhibit polysulfide shuttling. Previous studies mainly focus on the unidirectional catalysis conversion from S 8 to Li 2 S, and usually ignore the inverse reaction. Herein, defective vanadium nitride (VN 1−x) is designed to promote the conversion of sulfur. The catalytic analysis suggests that introducing nitrogen vacancies effectively improves the nucleation and decomposition kinetics of Li 2 S, and prefers to promote the nucleation process, leading to superior capacity. Benefit from the bidirectional enhanced sulfur redox kinetics, the VN 1−x /S composite electrode presents an impressively high capacity of 1417 mAh g−1 at 0.1 C at the first charge/discharge process, which is very close to the theoretical capacity of sulfur cathode (1675 mAh g−1). The Coulombic efficiency of the composite electrode reaches 99.89% even after 1000 cycles, showing reversible redox reactions. The pouch cell using VN 1−x /S cathode shows a high initial discharge capacity (1180.3 mAh g−1) and can stably cycle over 100 cycles. This work can support the development of bidirectional catalytic host design for high-loading Li-S batteries. [Display omitted] • VN with nitrogen vacancies is employed as the host to confine sulfur. • The enhanced bidirectional catalytic ability due to nitrogen vacancy is confirmed. • The VN 1-x /S assembled pouch cell presents a high initial capacity of 1180.3 mAh/g. [ABSTRACT FROM AUTHOR]

Abstract Carbon nanofibers (CNs) supported by Pt and Ni 2 P nanoparticles (Pt-Ni 2 P/CNs) are successfully synthesized and explored as counter electrodes for dye-sensitized solar cells (DSSCs) for the first time. Pt and Ni 2 P nanoparticles are prepared by stabilization and carbonization of electrospun nanofibers, and subsequently controllable Pt and Ni 2 P nanoparticles are grown on surface of CNs obtained through redox reaction. A series of electrochemical measurements analysis confirm that the Pt-Ni 2 P/CNs composite have simultaneously superior electrocatalytic activity and enhanced electrical conductivity compared with those of individual CNs and Pt. Accordingly, DSSCs using the composite Pt-Ni 2 P/CNs as a counter electrode exhibit an excellent photovoltaic performance (power conversion efficiency of 9.11%), which is much higher than conventional Pt/CNs counter electrode (power conversion efficiency of 8.35%), owing to the collective effect of the high electrical conductivity originated from carbon nanofibers and superior electrocatalytic activity arising from Pt/CNs nanoparticles. Highlights • Electrospun and solvothermal were used to synthesized Pt-Ni 2 P supported carbon nanofibers. • A novel composite of Pt-Ni 2 P/CN was introduced into DSSCs for counter electrode. • The DSSCs based on Pt-Ni 2 P/CN counter electrode yield a PCE of 9.11%. [ABSTRACT FROM AUTHOR]

Abstract Carbon cloth supported lamellar nickel-cobalt-molybdenum ternary phosphide (donated as NCMP) nanoarrays are prepared by a simple method including a hydrothermal and subsequent phosphorization process. The NCMP nanosheets are grown vertically on carbon cloth fibers (CC) to form a three-dimensional (3D) thin-wall cell structure with open pores (donated as NCMP@CC), which can be directly acted as working electrode without other binders or conductive additions, and achieves a specific capacitance as high as 433 F g−1 at a current density of 1 A g−1. Meanwhile, in order to match the capacitive behaviors of NCMP@CC in the two-electrode systems, hierarchically porous, nitrogen-doped, and interconnected carbon nanosheets (donated as HPN-CNS) are also prepared from agaric through a one-step method. An asymmetric supercapacitor device (ASC) is assembled successfully by employing the self-supported thin-wall cell structure NCMP@CC as positive electrode and the HPN-CNS as the negative electrodes, respectively. More importantly, the device exhibits not only high energy density of 43.83 W h kg−1 along with power density of 0.89 kW kg−1, but also an excellent cycle stability (82.4% after 10 000 cycles) under a cell voltage of 1.8 V. Graphical abstract Image 1 Highlights • 3D thin-wall cell structure Ni-Co-Mo ternary phosphide composites were prepared. • Hierarchically porous and nitrogen-doped carbon nanosheets were prepared from agaric. • NCMP@CC//HPN-CNS ASC device was assembled. • The NCMP@CC//HPN-CNS device showed high energy and power density. [ABSTRACT FROM AUTHOR]

Abstract Monodispersed spherical particles of ZrO 2 were synthesized in an aqueous medium by homogeneous precipitation without being using any capping agent. Results revealed that size and uniformity of the synthesized particles were greatly dependent upon the experimental conditions. SEM, XRD, and FT-IR were used for characterization of selected particle systems. SEM analysis showed the spherical morphology of the as-prepared particles, which remained unchanged even after calcination at 750 °C. XRD results presented poor crystalline nature of the as-prepared solid while the calcined solid was perfectly crystalline. Furthermore, Cu-ZrO 2 Nanocomposite coatings, containing variable amounts of the incorporated ZrO 2 nanoparticles were deposited on a steel substrate by the electrodeposition from a dispersion of ZrO 2 particles in aqueous solutions composed of copper sulfate, boric acid, and sulphuric acid. Effect of ZrO 2 concentration in the plating bath applied current and stirring rate of the coating mixture on the co-deposited ZrO 2 particles in the composite coatings were evaluated. It was noted that these parameters had noticeable effect on the particles content of the composite coatings. The deposited composite coatings were analyzed for their surface morphology and microhardness respectively by scanning electron microscope and microhardness tester. Similarly, wear resistance of the coated samples was determined by using Ball-On-Disc Tribometer, attached to data acquisition system for continuous monitoring of friction force at the sliding contacts. Selected batches of the coated substrates were tested for their response to corrosion tests at room temperature. It was observed that the amount of the embedded ZrO 2 particles in the composite coatings affected the cathodic polarization potential of the test samples. Conclusively, amount of the dispersed ZrO 2 particles in the copper matrix turned out to be the key parameter in controlling the properties of the composite coatings. Highlights • Monodispersed ZrO 2 was incorporated in Cu-ZrO 2 nanocomposite coating on steel by electrodeposition. • The embedded ZrO 2 in the composite was dependent upon its content in the coating mixture. • ZrO 2 particles affected the surface morphology & microstructure of composite coating. • Wear resistance & microhardness of the composite coatings turned out to higher than Cu coatings. • Cu-ZrO 2 composite coating exhibited enhanced corrosion resistance than pure Cu coating. [ABSTRACT FROM AUTHOR]

Abstract In recent years, capacitive deionization (CDI) has attracted intensive research due to its environmentally-friendly nature and low power requirement. Although the characteristics of titania (TiO 2) and zirconia (ZrO 2) are almost the same, ZrO 2 has not attracted the same attention since the characteristics of the carbonaceous material need to be modified to enhance its performance as an electrode in CDI cells. In this study, the wettability and electrochemical behavior of activated carbon (AC), as a widely used, effective, and inexpensive material, was distinctively improved by doping with zirconia nanoparticles. The introduced AC/ZrO 2 nanocomposite was fabricated using the alkaline hydrothermal method. Investigation of the surface morphology, phase and crystallinity by SEM, TEM, XPS, and XRD demonstrated the successful doping of AC by zirconia nanoparticles. Interestingly, the wettability measurement showed excellent enhancement, since the water contact angles of pristine and doped AC are 45° and 148°, respectively. The electrochemical experiments demonstrated that the synthesized composite (AC/ZrO 2) has a specific capacitance of 282.8 F g−1, which is higher than that for AC (207.5 F g−1). Due to the significant improvement in wettability and specific capacitance, the desalination performance and the salt ion electrosorption capacity were also enhanced: 40.4% and 68.5%, and 2.82 and 4.79 mg/g for AC and AC/ZrO 2 , respectively. Moreover, the introduced AC/ZrO 2 revealed 99% remaining desalination retention suggesting high stability. Overall, this study demonstrates ZrO 2 is an effective, stable, and environmentally safe material for improving the performance of carbonaceous CDI electrodes. Graphical abstract Image 1 Highlights • ZrO 2 NPs/AC is introduced as effective CDI electrode material. • The salt removal efficiency has been improved to 68.5%. • Good performance is due to improving the specific capacitance. [ABSTRACT FROM AUTHOR]

Abstract Two-dimensional porous nanodisks of NiCo 2 O 4 have been synthesized by low temperature hydrothermal method followed by calcination at 500 °C/3 h/air. X-ray diffraction pattern confirmed the phase purity of the sample. Microstructure analysis clearly exhibits a unique porous nanodisks shape of NiCo 2 O 4 sample. Brunauer–Emmett–Teller technique is also used to investigate the surface area and pore size of the sample. Electrochemical properties are evaluated via cyclic voltammetry and Galvanostatic cycling studies. NiCo 2 O 4 as an anode exhibits excellent lithium storage capacity (673.9 mAh g−1 at 0.5C after 350 cycles; 596.9 mAh g−1 at 3.0 C after 200 cycles), high initial Coulombic efficiency (75%), long cycling stability (∼80% capacity retention at 350 cycles) and better rate capability (552.5 mAh g−1at 4.0 C), which is much higher than the theoretical capacity of graphite (372 mAh g−1). This improvement can be attributed to the unique porous structure of the electrode, which allows maximum Li+ ion to react with electrode material, shortens the diffusion path length and increasing the electrode/electrolyte contact area. Highlights • Porous nanoplate of NiCo 2 O 4 was fabricated by facile hydrothermal method at 250 °C for 3 h. • Numerous pores such as mesopores and macropores were present on the nanoplate surface. • The open pores can facilitate the electrolyte diffusion and benefits in Li+ transportation. • The electrode shows excellent cycling stability and high rate capability. [ABSTRACT FROM AUTHOR]

Zr-doped BiVO 4 photoanodes modified with CoF 2 co-catalyst (Zr-CoF 2 /BiVO 4) were designed and synthesized by a simple two-step hydrothermal and calcination method. The photocurrent density of the prepared Zr-CoF 2 /BiVO 4 photoanode is as high as about 3.6 mA/cm2 at 1.23 V vs. RHE (AM 1.5 G). The excellent PEC performance benefits from the cocatalyst loading and the formation of heterojunction. The Zr-CoF 2 /BiVO 4 composite photoanode improves the transfer efficiency of photogenerated carriers and the yield of water splitting. Co2+ site in the CoF 2 co-catalyst has excellent water oxidation activity. The metal Zr doping further improves charge separation and conduction, thereby reducing the electron-hole complexation rate to affect PEC performance, enhancing photocurrent as well as oxygen release and providing an effective reference method for exploring solar water decomposition. This scheme provides an effective reference method for exploring solar water decomposition. [Display omitted] • Zr-CoF 2 modified BiVO 4 photoanodes by hydrothermal and calcination methods. • Zr-CoF 2 could effectively accelerate the interfacial kinetics of BiVO 4. • Zr-CoF 2 /BiVO 4 PEC water splitting is greatly improved. • The Faradaic efficiencies of nanocomposite electrode were both around 85%. [ABSTRACT FROM AUTHOR]

The protonated polyaniline prepared by protonated electropolymerization exhibited a higher density of states at the Fermi energy level. Then, by depositing silver on the electrode surface, high electrocatalytic activity and good stability of silver/protonated polyaniline-titanium (Ag/H-PANI-Ti) electrodes were produced. The degradation efficiency of the Ag/H-PANI-Ti electrode for doxycycline hydrochloride (DOX) reached 83.33 % in 120 min under optimal parameters and in accordance with the pseudo primary reaction kinetics. The energy consumption was only 15.84 kWh/kg. The mechanism of DOX degradation through cathodic and anodic co-catalysis was put forth, and the degradation pathway was deduced. It should be highlighted that toxicology tests and toxicological evaluation based on ecological conformational relationships (ECOSAR) revealed that the biological toxicity of DOX was greatly decreased following degradation by the Ag/H-PANI-Ti electrode. Finally, the mechanism of enhanced Ag/H-PANI-Ti performance was illustrated by DFT first-nature principle calculations. The results showed that this study provides a viable option for the electrocatalytic degradation of antibiotics. [Display omitted] • Protonic acid-doped polyaniline enhances conjugation and improves conductivity. • Ag/H-PANI-Ti electrode exhibited good reusability and low energy consumption. • The degradation pathway of DOX by Ag/H-PANI-Ti electrode was inferred. • •OH and reactive atomic H* play a role in the degradation of DOX. • The degradation products of DOX are less toxic to E. coli and aquatic organisms. [ABSTRACT FROM AUTHOR]

In this study, the partially sulfidized Ni-Co/reduced graphene oxide (NCS/NC/RGO) hybrid was developed as a supercapacitor electrode material. Because Ni-Co sulfide (NCS) possessed good pseudocapacitor property and non-sulfidized Ni-Co (NC) alloy had high conductivity, we attempted to optimize the electrochemical performance of NCS/NC/RGO hybrid by controlling the sulfidation of NC/RGO hybrid. RGO was incorporated as a substrate to help the dispersion of NCS/NC nanoparticles and contribute some capacitance. It was demonstrated that an appropriate sulfidation of NC/RGO hybrid could lead to the highest capacitance effectively. Moreover, the optimal NCS/NC/RGO hybrid also exhibited good stability. The result revealed that the strategy to optimize the capacitor performance of NCS/NC/RGO hybrid via the controlled sulfidation of NC/RGO hybrid was indeed effective. [ABSTRACT FROM AUTHOR]

Nanostructured α-Fe 2 O 3 films doped with niobium and supported with CoPi cocatalyst (Nb-α-Fe 2 O 3 @CoPi) are prepared by hydrothermal growth together with electrochemical deposition. The effect of Nb doping and CoPi cocatalyst modification on the performance of photoelectrochemical water oxidation and methylene blue degradation of α-Fe 2 O 3 is studied in detail. It shows that Nb doping and CoPi modification toward α-Fe 2 O 3 not only enhances its light absorption, but also improves its electrical properties, including conductivity, bulk charge separation efficiency and charge transfer efficiency at the electrode/electrolyte interface. When used as photoanode for photoelectrochemical water oxidation, the Nb-α-Fe 2 O 3 @CoPi photoanodes show a negative shift of 540 mV in the onset potential in comparison with the pristine α-Fe 2 O 3 films. At the same time, the photocurrent density (at 1.6 V, vs. RHE) of Nb-α-Fe 2 O 3 @CoPi is more than three times that of the pristine α-Fe 2 O 3 , reaching 1.44 mA·cm−2. In addition, the obtained Nb-α-Fe 2 O 3 @CoPi photoanodes also show excellent performance in visible light-driven photoelectrochemical degradation of methylene blue, a common pollutant in wastewater. For example, a degradation rate of 98% is achieved in 2 h by the Nb-α-Fe 2 O 3 @CoPi, which is 3.6 times that of the pristine α-Fe 2 O 3 (26%). [Display omitted] • Nb doping increases the donor density of α-Fe 2 O 3. • Nb doping enhances the light adsorption of α-Fe 2 O 3. • Nb doping improves the bulk charge transport efficiency of α-Fe 2 O 3. • CoPi modification reduces the charge transfer resistance of Nb doped α-Fe 2 O 3. • Nb doping and CoPi modification synergistically improve the PEC performance of α-Fe 2 O 3. [ABSTRACT FROM AUTHOR]

The development of electrode materials with nanostructures is of great importance in the field of supercapacitors. In the present research, the direct simultaneous deposition of Ni-Co nanosphere (Ni-Co NS) on nickel foam as a substrate has been performed by facile one-step electrodeposition method without any template to provide excellent electrical conductivity and efficiency of electrode materials. The SEM images of Ni-Co NS electrode showed a nanosphere shape. The electrochemical performance of the electrodeposited nanosphere has been investigated by cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy in 3 M KOH aqueous electrolyte. The Ni-Co NS electrode showed a good specific capacity of 564.6 C g−1 at 2 A g−1 with rate capability of 70% in the current density range of 2–20 A g−1, reasonable cyclic stability of 86% after 5000 cycles at the scan rate of 70 mV s−1, low internal resistance, and high surface area of the nanospheres. Interestingly, an asymmetric supercapacitor fabricated using Ni-Co NS and activated carbon as the positive and negative electrodes, respectively, operating at the potential window of 1.5 V delivered high energy and power densities of 34.5 Wh kg−1 and 683 W kg−1, respectively. • Ni-Co nanospheres were fabricated as positive electrode via electrodeposition method. • Ni-Co NS illustrated specific capacitance of 564.6 C g−1 at 2 A g−1. • Ni-Co NS electrode was used as high-performance asymmetric supercapacitor. • The asymmetric supercapacitor showed impressive energy density of 34.5 Wh. kg−1 and a power density of 683 W. kg−1. [ABSTRACT FROM AUTHOR]

All-solid-state Li-S batteries are fabricated with lithium silicide anodes (Li 4.4 Si), sulfide-based glass electrolyte (Li 2 S-P 2 S 5 ), and sulfur composite (sulfur + acetylene black + solid electrolyte) cathode. Various preparation methods, such as mortar mixing (MM), ball milling (BM), and secondary ball milling (SBM), are applied for the sulfur composite cathode. By changing the preparation methods from MM to SBM, the electrode morphology and the electrolyte/cathode interfacial area are significantly improved, as confirmed with BET, SEM/EDS, and GITT analyses. These effects are reflected in the charge-discharge tests, resulting in higher capacity of the SBM cell. Pyrolytic graphite sheet (PGS) is employed for the gradient structure of the sulfur composite cathode, and the cell with PGS shows higher volumetric capacity and equivalent gravimetric capacity than do cells with the conventional cathode structure. This is because the cathode thickness is reduced and the electron transport to/from the current collector is facilitated. Thus, the present work indicates that design and preparation of the electrode greatly affects the performance of solid state batteries with sulfur composite cathodes. [ABSTRACT FROM AUTHOR]

With the development of power supplies for wearable devices, electrode materials with dual functions have received extensive attention. Herein, we report a strategy of preparing stylophora coral-like Ni/Co bimetal metal organic framework (MOF) with furan-based derivatives as ligands through the simple solvothermal method, which can be utilized as a dual-function electrode material to build supercapacitors and non-enzymatic glucose sensing. It can be found that the high molecular stacking properties of the rigid furan ring skeleton combined with the unique stylophora coral-like morphology can greatly improve the charge transfer efficiency of the electrode reaction process, and the structure of the bimetallic node can effectively adjust the three-dimensional electronic structure, making high capacitive performance during charge storage. The specific capacitance of the furan-based bimetallic MOF material is as high as 531 C g−1 at a current density of 1 A g−1 with a high capacitance retention rate of 83.4% after 5000 cycles. In addition, the glucose sensing performance is analyzed and an outstanding sensitivity value of 366 µA mM−1 cm−2 is achieved with a low limit of detection (2 μM). The as-synthesized furan-based bimetallic MOF material is a promising candidate for electrochemical supercapacitors and efficient glucose detection. [Display omitted] • ·Furan with high carrier mobility and high π electron delocalization as the ligands. • ·The stylophora coral-like structure promoted the electrochemical reaction. • The Ni/Co-FAMOF electrode shows a high specific capacitance of 531 C g-1 at 1 A g-1. • ·Ni/Co-FAMOF exhibits excellent properties in supercapacitors and glucose sensing. [ABSTRACT FROM AUTHOR]

In this study, gold (Au) and poly(3-hexylthiophene) (P3HT) composite nanoparticles (Au@P3HT) are synthesized and applied to modify the photoelectrodes of dye-sensitized solar cells (DSSCs). The modification is carried out by adsorption of Au@P3HT onto the electrode surface. The experimental results show that the Au@P3HT nanoparticles demonstrate a spherical shape with a mean diameter of 6 nm. The analysis of X-ray photoelectron spectroscopy indicates that the P3HT strongly interact with Au, protecting the Au particles from the corrosion of iodide electrolytes. Scanning electron microscope analysis reveals that the Au@P3HT nanoparticles adsorb strongly and uniformly on the mesoporous TiO 2 photoelectrode. The UV–vis absorption spectrum shows that the Au@P3HT-modified photoelectrode can enhance the light absorption in the long wavelength region, attributed to the plasmon resonance effect of Au nanoparticles. It also demonstrates that the modification of Au@P3HT not only improves the incident photon to current conversion efficiency but also increases the recombination resistance at the photoelectrode/electrolyte interface. Therefore, the corresponding cell has higher current density and open-circuit voltage. By way of this method, the DSSC can achieve an energy conversion efficiency of 9.34%. The non-corrosive characteristics of the Au@P3HT-modified electrode against the iodide liquid electrolyte improve the durability of the DSSCs. [Display omitted] • Au@P3HT is synthesized and utilized to modify the photoelectrodes of DSSCs. • Au@P3HT and P3HT electrodes are prepared using the adsorption-desorption methods. • The high penetration of the Au@P3HT composite into the TiO 2 layers is observed. • The cells have high recombination resistance and a longer electron lifetime. • The cells using Au@P3HT-modified electrodes had efficiencies of 9.34%. [ABSTRACT FROM AUTHOR]

Interface modification of indium tin oxide (ITO) is a hot research topic to obtain highly efficient and stable organic light-emitting diodes (OLEDs), and the key point is to improve the hole injection efficiency between the electrode and organic layer. In this study, we demonstrate an optimization strategy based on the use of 3-aminobenzeneboronic acid (3ABBA) for modifying ITO at the anode interface. The protonation reaction of boronic acid groups with oxides and hydroxyl groups forms a self-assembled monolayer (SAM). Since the ionization potential (I P) of 3ABBA-SAM is 5.44 eV, the hole injection barrier at the interface is minimized. Compared with a control device using PEDOT:PSS, the synergistic effects of the optimized 3ABBA-SAM significantly improves the maximum power efficiency (PE max of 8.52 lm W−1) and maximum current efficiency (CE max of 10.45 cd A−1) of the device, and the turn-on voltage is reduced by 0.2 V. In addition, effective interface modification reduces the hydrophilicity of the device and provides support for the stability of the OLED in the ambient environment. Therefore, we believe that a simple 3ABBA-SAM interface modification project can promote the development of high-performance and low-cost OLEDs. • The ITO interface modified by 3-Aminobenzeneboronic acid is reported for the first time. • The self-assembled monolayer reduces the hole injection barrier and promotes. • Compared with PEDOT:PSS as hole injection layer, the device shows better performance and lower cost. [ABSTRACT FROM AUTHOR]

• Cu-doped NiO electrocatalyst was examined for urea electrocatalysis. • Microwave-assisted hydrogel method was used for preparation of metal oxides. • Electrochemical impedance spectroscopy studies were used to evaluate the charge transfer properties of urea electrooxidation. • DFT of CO adsorption was studied onto Cu-doped NiO surface. [Display omitted] In the present work, Cu-doped NiO is fabricated and synthesized using a microwave-assisted sol-gel method using different Ni and Cu precursors ratios supported on commercial graphite rod (G) and examined as an efficient electrocatalyst toward urea electrochemical oxidation (UEO). The morphology and chemical structure of the prepared electrocatalysts is confirmed by XRD, XPS, and SEM techniques. The catalytic activity of the prepared materials is measured and examined toward UEO as a function of current density and compared with different Ni-based catalysts in NaOH solution using cyclic voltammetry, chronoamperometry, and electrochemical impedance spectroscopy (EIS). The oxidation current density of G/Ni 0.9 Cu 0.1 reached 32 mA cm-2 , and its onset potential of urea oxidation peak is shifted from 0.43 V (vs. Ag/AgCl) in NiO catalyst to 0.40 V (vs. Ag/AgCl) for G/Ni 0.9 Cu 0.1. The charge transfer resistance for different modified surfaces at various conditions (e.g., urea concentration, electrolyte concentration, and oxidation potential) is measured using the electrochemical impedance spectroscopy (EIS). The CO tolerance is studied using the DFT method to prove the stability of the electrodes and the performance efficiency due to Cu atoms dopping into NiO crystal. The adsorption of CO is studied upon Cu-doped NiO and compared with pristine NiO alloy at different adsorption sites- top and hallow. [ABSTRACT FROM AUTHOR]