Pure Cobalt Research Articles

Preparation of cobalt-RuO2 nanocomposite modified electrode for highly sensitive and selective determination of hydroxylamine

Herein, we report the facile synthesis of cobalt and cobalt-RuO2 nanocomposite modified electrode using electrodeposition method and utilized as an electro catalyst for electro oxidation of hydroxylamine. The surface morphology and the chemical composition of cobalt and cobalt-RuO2 nanocomposite were examined using FESEM, TEM, EDAX and XPS analysis. FESEM images inferred that the cobalt Nano flakes are uniformly deposited on the mild steel substrate in which the ruthenium oxide nanoparticles are randomly incorporated. EDAX analysis also confirmed the presence of cobalt, ruthenium and oxides in the electrodeposits. The predominant orientation and the crystal structure were obtained from XRD patterns. The crystal growth is preferably in (100) plane corresponding to hexagonal closed packed structure of cobalt and the reflections of RuO2 particles are at 2θ=28.00. The electro oxidation of hydroxylamine at pure cobalt and cobalt-RuO2 nanocomposite electrode was investigated with cyclic voltammetry (CV). The onset potential of hydroxylamine oxidation on cobalt-RuO2 electrode starts at −0.09V which is comparatively lower than pure cobalt. In addition to that, upon increasing the hydroxylamine concentration, the anodic oxidation peak gets increased with the decrease in the catholic reduction peak suggesting that the proposed material had a good electro catalytic activity for the electro oxidation of hydroxylamine.

Cobalt oxides-sheathed cobalt nano flakes to improve surface properties of carbonaceous electrodes utilized in microbial fuel cells

A novel nanoflakes of cobalt sheathed with cobalt oxide is electrodeposited on four different carbonaceous anodes; carbon cloth (CC), carbon paper (CP) graphite (G) and activated carbon (AC), to introduce as high-performance anodes of microbial fuel cell (MFC). Interestingly, characterizations results indicated that novel metallic nanoflakes that sheathed by a thin layer of cobalt oxide were formed on the surface of the different anode materials. Moreover, using a simple and effective electrodeposition technique for fabricating of cobalt/cobalt oxide nanoflakes is introduced to overcome the hydrophobicity and the interfacial electron transfer of the anodes. The thin layer of cobalt/cobalt oxide nanoflakes significantly enhanced the microbial adhesion, the wettability of the anode surface and decrease the electron transfer resistance. Alternatively, the toxicity risk of the pure cobalt is overcome by the cobalt oxide layer. The application of the modified anodes in an air-cathode MFCs fed by industrial wastewater resulted in a significant improving in cell performance for the different anode materials. Where, the observed increasing in the power was 103, 137, 173 and 71% for the CC, CP, G and AC electrodes, respectively. This proposed treatment technique represented a high-performance, excellent microbial adhesion, easy fabrication and scale-up anodes for MFC.

Hydrothermal Synthesis of Monolithic Co3Se4 Nanowire Electrodes for Oxygen Evolution and Overall Water Splitting with High Efficiency and Extraordinary Catalytic Stability

Cobalt selenide has been proposed to be an effective low‐cost electrocatalyst toward the oxygen evolution reaction (OER) due to its well‐suited electronic configuration. However, pure cobalt selenide has by far still exhibited catalytic activity far below what is expected. Herein, this paper for the first time reports the synthesis of new monoclinic Co3Se4 thin nanowires on cobalt foam (CF) via a facile one‐pot hydrothermal process using selenourea. When used to catalyze the OER in basic solution, the conditioned monolithic self‐supported Co3Se4/CF electrode shows an exceptionally high catalytic current of 397 mA cm−2 at a low overpotential (η) of 320 mV, a small Tafel slope of 44 mV dec−1, a turnover frequency of 6.44 × 10−2 s−1 at η = 320 mV, and excellent electrocatalytic stability at various current densities. Furthermore, an electrolyzer is assembled using two symmetrical Co3Se4/CF electrodes as anode and cathode, which can deliver 10 and 20 mA cm−2 at low cell voltages of 1.59 and 1.63 V, respectively. More significantly, the electrolyzer can operate at 10 mA cm−2 over 3500 h and at 100 mA cm−2 for at least 2000 h without noticeable degradation, showing extraordinary operational stability.

Nanostructured cobalt oxide and cobalt sulfide for flexible, high performance and durable supercapacitors

Transition metal oxides and sulfides have great potential for energy storage devices due to their large theoretical energy storage capacities. A facile technique was used for the synthesis of nanostructured and phase pure cobalt oxide (Co3O4) and subsequently converting it to cobalt sulfide (Co9S8). The effect of sulfurization on energy storage capacity of the cobalt oxide was explored. Microstructural characterizations using X-ray diffraction and scanning electron microscopic reveal formation of phase pure and nanostructured Co3O4 and Co9S8. It was observed that the areal capacitance of Co3O4 (983mF/cm2) improved significantly after converting to Co9S8 (7358mF/cm2). The CV curves of the Co9S8 electrode on bending showed outstanding stability with no change in energy storage properties. New insights into the better performance of Co9S8 over Co3O4 based on electrochemical investigations are presented. The performance of the Co9S8 as an electrode material for energy storage applications was further investigated by fabricating a supercapacitor device. The supercapacitor device showed outstanding stability up to 5000 cycles of charge-discharge study. The performance of the supercapacitor was observed to be improving with temperature. The supercapacitor displayed ~100% enhancement in energy storage property on increasing temperature from 10 to 70°C. Our results suggest that hydrothermally grown Co9S8 on nickel foam can be utilized for high capacity, flexible and binder free electrode for energy storage applications.

Co−doped stannates ⁄reduced graphene composites: Effect of cobalt substitution on the electrochemical sensing of hydrogen peroxide

Co−doped stannates, Zn2-xCoxSnO4 (0.5≤x≤1.5), were produced by ceramic synthesis starting from the ZnSnO4 phase. Morphology, structure, and composition of synthesized compounds were examined using scanning electron microscopy, X-ray diffraction analysis (XRD), and X-ray photoelectron spectroscopy (XPS). Using XPS, cobalt ions are shown to have an oxidation state of 2+, and XRD patterns showed the same crystalline structure for all Zn2-xCoxSnO4 (0.5≤x≤1.5) phases, i.e., they are isostructural. The morphology of synthesized compounds shows appreciable differences in particle sizes which range from 80nm to 500nm, depending on how the ceramic was synthesized and the cobalt concentration. Co−doped stannates ⁄reduced graphene (rGO) composites were prepared and used to modify glassy carbon electrodes (GCE). The resulting electrodes were evaluated for the amperometric determination of hydrogen peroxide. The catalytic activity of composites towards the oxidation of hydrogen peroxide was highly dependent on quantity of cobalt in the ceramic compound, and also on the quantity of rGO present in the composite. The pure cobalt stannate phase with a ratio of 8:1 (ceramic:rGO) exhibited the best catalytic activity towards hydrogen peroxide oxidation at low potentials (0.400V). A linear relationship between current and hydrogen peroxide concentration was obtained with a sensitivity of 0.43μAmM−1cm−2 and a detection limit of 0.31μM.

Study on the establishment of HMLD model and the expression of KL-6/TGF-beta in rat

Objective: To establish an animal model of hard metal lung disease (HMLD) in rats, and to screen the indications for diagnosis of HMLD. Methods: The rats were randomly divided into 5 groups, each group included 8 rats: saline group, pure cobalt group, pure tungsten carbide group, silica group and hard metal (HM) group. 10 mg subjects were administered in each group by using the pulmonary endotracheal tube. After 8 week, the lung CT scan and lung tissue pathology were observed, the serum and bronchoalveolar lavage fluid (BALF) were collected for KL-6, TGF-beta1 and TGF-beta2. Results: The lung tissue structure of HM group was destroyed, a large number of nuclear giant cells and epithelial like cells appeared in the stroma, and uncommon CT scan images appeared in the lung. KL-6, TGF-beta1, TGF-beta2 expression in each group was not the same, the difference was statistically significant (P<0.05) . The expression of KL-6 and TGF-beta1 in serum was not identical in all the groups, the difference was statistically significant (P<0.05) . The expression of TGF-beta2 had no significant difference between the groups (P>0.05) . Conclusion: Rats can be successfully established HMLD model, rats in vivo lung CT scan images appear abnormal, which are provided with assistant diagnostic value for HMLD. The expression of KL-6 and TGF-beta2 in serum and BALF on HMLD rats are not highly specific, and TGF-beta1 has reference value in the rat HMLD auxiliary diagnosis.

Starch-assisted electrochemical fabrication of high surface area cobalt hydroxide nanosheets for high performance supercapacitors

High surface area β-Co(OH)2nanosheets is electro-synthesized through a simple deposition procedure, and their performance as supercapacitor electrode material is investigated. Cathodic electrodeposition of cobalt hydroxide was performed from 0.005 M CoCl2 at the direct current (DC) mode with applying current density of 10 mA cm−2 and RT conditions. The obtained green deposit was characterized through XRD, IR, SEM, BET and TEM analyses. The result indicated that the electrodeposited sample has pure beta cobalt hydroxide phase with uniform hexagonal sheets. BET analysis showed that the prepared hydroxide has high surface area of 157.2 m2 g−1 with mesoscale pores. The charge storage ability of the prepared β-Co(OH)2 nanosheets were measured by cyclic voltammetry and continuous charge–discharge techniques, which revealed that the produced nanosheets are capable to deliver specific capacitance as high as 886.8 and 734.3 Fg−1 at the current loads of 1 and 3 A g−1, respectively, and capacity retentions of 93.9 and 83.7% after 3000 continuous cycling at these current loads. These electrochemical data proved the suitability of the prepared material for use in supercapacitor.

Electronically tailoring 3D flower-like graphene via alumina doping and incorporating Co as an efficient oxygen electrode catalyst in both alkaline and acid media

3D graphene-based electrode catalysts have intrigued tremendous research in energy conversion and storage systems not only for the intrinsic properties of graphene, but also due to its high active density for the oxygen electrode reaction with efficient mass and electron transports. In this work, we try to electronically tailor 3D nitrogen-doped graphene (NG) using alumina (Al), and obtain the flower-like structure with a high Brunauer–Emmett–Teller (BET) surface area and abundant active sites, as a result, pure cobalt nanoparticles are easily confined. Physical characterizations confirm that this natural tuning of graphene by Al causes the increasing of surface defects, as a result, the physicochemical stability of Al and graphene is improved, and vice versa, consequently, the co-modification of Al and Co induce outstanding oxygen reduction reaction (ORR) performance including distinct onset potential, large diffusion limiting current density, kinetic current density and good stability, which are comparable with those of 20 wt% Pt/C in both alkaline and acidic media; in addition, the fabricated composite also delivers prior oxygen evolution reaction activity, superior to the benchmark RuO2. This hybrid herein exhibits a combined ORR and OER potential gap of 0.745 V, rivaling state-of-the-art bifunctional oxygen electrode catalysts.

Electrolytic separation of cobalt and tungsten from cemented carbide scrap and the electrochemical behavior of metal ions

Molten salt electrolysis is used to separate and recycling of elemental tungsten and cobalt from cemented carbides. WC–6wt% Co scrap and NaCl–KCl molten salt was used as a sacrificial anode and electrolyte, respectively. The range of preparation parameters and the electrochemical behavior of tungsten and cobalt ions were investigated through electrochemical techniques, such as cyclic voltammetry (CV) and square wave voltammetry (SWV). Results showed that the dissolution potential of cobalt and WC were 0V and 0.6V (vs. Ag/AgCl), and the reduction potentials of Co (II)+2e− ↔ Co (0) and W(II)+2e− ↔ W (0) were −0.2 and 0.2V (vs. Ag/AgCl), respectively. The reduction processes of Co(II) to Co and W(II) to W were both reversible reactions controlled by ion diffusion. The average diffusion coefficients of Co(II) and W(II) were determined by CP to be 5.62×10−5and 3.94×10−5cm2s−1, respectively. Furthermore, the products at cathodes Nos. 1 and 2 were characterized by scanning electron microscopy, X-ray fluorescence and X-ray diffraction analyses. Results showed that pure cobalt and WC powder with a diameter of <100nm was obtained at cathode No. 1 and cathode No. 2. And the result of XRF shows that the purity of the products both Co and WC were higher than 90%. This study reveals that cobalt and tungsten can be separated from WC–6wt% Co scrap by controlling process parameters during electrolysis.

Fretting wear of pure cobalt chromium and nickel to identify the distinct roles of HS25 alloying elements in high temperature glaze layer formation

HS25 cobalt-based superalloy was investigated between 100 and 600°C under fretting wear (small amplitude reciprocating displacements) in a cross-cylinder contact. Tribological behavior was compared to pure cobalt, chromium and nickel tested under the same conditions and analyzed in terms of friction, wear, interface morphology and chemical composition by SEM-EDX and Raman spectroscopy. On HS25, the tribological tests resulted in the formation of a “glaze layer” of ground and compacted wear debris, which was protective against severe wear and high friction above 250°C. Similar glaze layers were found for cobalt-cobalt (Co//Co) contacts, suggesting the determining role of cobalt in glaze layer formation whereas worn Cr//Cr and Ni//Ni interfaces exhibited poorly sintered debris and respectively adhesive and abrasive wear. To identify the role of alloying elements in glaze layer formation, the oxides formed in the interface were studied in terms of composition and thermal stability. As sintering appears to be a determining factor in glaze layer formation, the diffusion properties of cobalt and its oxides are emphasized. The strengthening and corrosion resistance properties of chromium and nickel in the alloy are also discussed.

Effect of the Metal Ion on the Enantioselectivity and Linkage Isomerization of Thiosemicarbazone Helicates

The effect of the metal ion and ligand design on the enantioselectivity and linkage isomerization of neutral cobalt and zinc bisthiosemicarbazone metallohelicates has been investigated in this work. The electrochemical synthesis has afforded the enantioselective formation of chirally pure cobalt helicates, and the ΛΛ isomer of a single enantiomer has been crystallized as only product for the cobalt methyl-substituted thiosemicarbazone helicate. Interestingly linkage isomers have been formed from zinc ethyl-substituted thiosemicarbazone helicate enantiomers for the first time. The co-existence of these isomers has been evaluated from the point of view of both experimental results and computational calculations.

Vacancy filled nickel‐cobalt‐titanate thin films

Single phase nickel‐cobalt‐titanate thin films with a formula A1+2xTi1−xO3, where A is Ni2+,Co2+, and −0.25 &lt; x &lt; 1, were grown by pulsed laser deposition on sapphire substrates. There is a large window in which Ni/Co ratio and x can be chosen independently, allowing a control of properties by the synthesis. In the prototype ilmenite and corundum structures one third of the octahedra are vacant. The reported structure is obtained by filling vacant octahedra (x &gt; 0) or emptying filled octahedra (x &lt; 0). Films with x = 1 have all octahedra filled. X‐ray photoelectron spectroscopy, X‐ray diffraction measurements and Raman scattering techniques were applied to address the structure as a function of x. Data collected on samples with x ≈ 1 are interpreted in terms of hexagonal P63/mmc space group. The hexagonal structure was obtained when films contained both Ni and Co: pure cobalt oxide thin films possessed the spinel structure. Two factors controlling the magnetism and crystal distortion are identified: a direct overlap between the adjacent cation d‐orbitals resulting in a bond formation and magnetic interactions, and x controlling the cation shift toward the vacant octahedron. The displacement decreases and the symmetry increases with increasing x. When x ≈ 1 the cations prefer octahedron center positions.

Low temperature synthesis of Co3O4 and (Co1−xMnx)3O4 spinels nanoparticles

The (Co1−xMnx)3O4 solid solution have been synthesized in water at 60°C by soda addition to a cationic solution. XRD patterns show that spinel oxide has been obtained except for pure cobalt composition which exhibits also the presence of hydroxide and oxy-hydroxide. Therefore, to reach this composition, a different synthesis route has been developed: the cationic solution is added to the soda and for the first time Co3O4 nanoparticles have been synthesized by a direct precipitation in aqueous solution at low temperature. For each composition, the particles are well crystallized and exhibit a size close to 50nm. Each particle is composed by several crystallographic domains of about 10nm. The cubic to tetragonal transition reported in the literature for x=0.46 is observed in between x=0.33 and x=0.50. Raman spectra show that substitution of Co by Mn, in the cubic phase, introduces a random high disorder. In the tetragonal phase, occupation of the octahedral site remains a random occupation, while the tetrahedral site seems to be preferentially occupied by Co ions. All these results show that the precipitation is a simple, fast and safe process to synthesize pure phase of (Co1−xMnx)3O4 spinel solid solution in aqueous media at low temperature.

Synthesis, Crystal Structure, and Magnetic Properties of a New Mixed Metal (Co(II), Ni(II)) Cubane.

The mixed Co(II)/Ni(II) complex, [Co2.67Ni1.33L4(CH3COO)2][BPh4]2·0.75H2O where HL = 4-(salicylaldimine)antipyrine, was isolated as an orange solid from the reaction of 4-(salicylaldimine)antipyrine, with mixed cobalt(II) acetate and nickel(II) acetate in ethanol. The complex was characterized by Frustrated Total Internal Reflection (FTIR), UltraViolet Visible spectroscopy (UV-Vis), X-ray single crystal diffraction, and by elemental analysis. The complex is composed of two symmetry independent cationic units, A and B. The two units are essentially isostructural; nevertheless, small differences exist between them. The units contain four metal atoms, arranged at the corners of a distorted cubane-like core alternately with phenoxy oxygen of the Schiff base. The overall eight corners occupied by metal ions in the asymmetric unit are shared between cobalt and nickel in a 5.33:2.67 ratio. Each metal divalent cation binds three coordinated sites from the corresponding tridentate Schiff base ligand, the fourth one is bound by the acetate oxygen, the fifth and the sixth donor sites come from the phenolate oxygens of other Schiff base ligands. Intermolecular hydrogen bonds join the complexes to the water molecules present in the crystal packing. The magnetic characterization was carried out for this new complex and for its isostructural counterpart containing only cobalt ions. The magnetic measurements for the cobalt(II)/nickel(II) mixed compound indicate either antiferromagnetic interactions among the two cubanes or an anisotropic contribution, whereas a ferromagnetic interaction is observed within the cubane, for both the complexes, as expected by geometrical considerations. A comparison between the magnetic properties of the pure cobalt(II) derivative and similar systems discussed in literature, is presented.

MOF-Derived Hollow Cage Nix Co3-x O4 and Their Synergy with Graphene for Outstanding Supercapacitors.

Highly optimized nickel cobalt mixed oxide has been derived from zeolite imidazole frameworks. While the pure cobalt oxide gives only 178.7 F g-1 as the specific capacitance at a current density of 1 A g-1 , the optimized Ni:Co 1:1 has given an extremely high and unprecedented specific capacitance of 1931 F g-1 at a current density of 1 A g-1 , with a capacitance retention of 69.5% after 5000 cycles in a three electrode test. This optimized Ni:Co 1:1 mixed oxide is further used to make a composite of nickel cobalt mixed oxide/graphene 3D hydrogel for enhancing the electrochemical performance by virtue of a continuous and porous graphene conductive network. The electrode made from GNi:Co 1:1 successfully achieves an even higher specific capacitance of 2870.8 F g-1 at 1 A g-1 and also shows a significant improvement in the cyclic stability with 81% capacitance retention after 5000 cycles. An asymmetric supercapacitor is also assembled using a pure graphene 3D hydrogel as the negative electrode and the GNi:Co 1:1 as the positive electrode. With a potential window of 1.5 V and binder free electrodes, the capacitor gives a high specific energy density of 50.2 Wh kg-1 at a high power density of 750 W kg-1 .

Temperature dependent magnetic properties of Co1+xTxFe2−2xO4 (T = Zr, Ti)

This study demonstrates the temperature dependent (carried out at 5, 150 and 300 K) magnetic properties of Zr4+ and Ti+4 substituted cobalt ferrite samples and their comparison. Polycrystalline Co1+xTxFe2−2xO4 (0 ≤ x ≤ 0.4 and T = Zr, Ti) series of compositions were prepared by conventional ceramic method. X-ray diffraction (XRD) confirmed the single phase cubic spinel structure, except for x = 0.4 composition. Coercivity (Hc) is observed to increase substantially with decrease in temperature for all Zr and Ti substituted samples. The magnetization and magnetocrystalline anisotropy constant (K1) were observed to peak at ∼150 K for both the series of samples. Field sensitivity of magnetization (dM/dH) increased with progressive Zr and Ti substitutions. Curie temperature of Co1.2Zr0.2Fe1.6O4 and Co1.2Ti0.2Fe1.6O4 samples (∼445 °C and 472 °C respectively) decreased compared to that of pure cobalt ferrite (∼517 °C).

CFO-Graphene nano composite for High Performance Electrode Material

CoFe2O4-graphene nanocomposite with different graphene content (5, 10 and 15 wt%) were synthesized by the high energy planetary Ball mill method using zirconium coated steel balls with a speed of 300 rpm for 24 hours. The structural properties and molecular vibrations or rotations of the material were studied by the XRD and Raman spectroscopy respectively. The electrical impedance (Zˈ) characterization reveals the increase in ac conductivity (σac) with the increase in graphene percentage in the composite as compared to pure cobalt ferrite. The conducting nature of graphene is also being reflected by the Nyquist plot. It is very interesting to note that the combination of CoFe2O4 nanoparticles with graphene results in a dramatic conversion of the inactive CoFe2O4 into a highly conductive composite, which is suited as electrode material in energy storage devices (supercapacitors, batteries, fuel cells and solar cells). The significant enhancement in conductivity under the applied electric field of 2 V (peak to peak) and frequency range 1 Hz to 1 MHz has been observed at room temperature due to addition of graphene in the CoFe2O4.

Recovery of valuable metals from waste cathode materials of spent lithium-ion batteries using mild phosphoric acid

Sustainable recycling of valuable metals from spent lithium-ion batteries (LIBs) may be necessary to alleviate the depletion of strategic metal resources and potential risk of environmental pollution. Herein a hydrometallurgical process was proposed to explore the possibility for the recovery of valuable metals from the cathode materials (LiCoO2) of spent LIBs using phosphoric acid as both leaching and precipitating agent under mild leaching conditions. According to the leaching results, over 99% Co can be separated and recovered as Co3(PO4)2 in a short-cut process involved merely with leaching and filtrating, under the optimized leaching conditions of 40°C (T), 60min (t), 4 vol.% H2O2, 20mLg−1 (L/S) and 0.7mol/L H3PO4. Then leaching kinetics was investigated based on the logarithmic rate kinetics model and the obtained results indicate that the leaching of Co and Li fits well with this model and the activation energies (Ea) for Co and Li are 7.3 and 10.2kJ/mol, respectively. Finally, it can be discovered from characterization results that the obtained product is 97.1% pure cobalt phosphate (Co3(PO4)2).

Controlled Synthesis, Characterization, and Photocatalytic Application of Co2TiO4 Nanoparticles

In the current study, an attempt is made to synthesize Co2TiO4 nanoparticles through the simple two-step sol–gel method with the aid of titanium(IV) isopropoxide and cobalt(II) acetate tetrahydrate as starting reagents in the presence of ethanol as a solvent. Additionally, the effects of sodium hydroxide and oxalic acid as the pH controller agents on the morphology and particle size of the products were investigated. Furthermore, effects of several natural and chemical surfactants such as starch, lactose, glucose, oleyl amine, and sodium dodecyl sulfate (SDS) on the morphology and particle size of final products were investigated. Based on the scanning electron microscopy (SEM) results, the above-mentioned parameters have a direct effect on the morphology and particle size of Co2TiO4 nanoparticles. The x-ray diffraction (XRD) results showed that pure cubic cobalt titanium oxide nanoparticles were obtained by this method after heat treatment at 600 and 900°C. Moreover, in the presence of Co2TiO4 nanoparticles as photocatalyst, the percentage of methyl orange (MO) degradation was about 100% after 40 min of irradiation of ultraviolet (UV) light.

Direct Electrochemical Preparation of Cobalt, Tungsten, and Tungsten Carbide from Cemented Carbide Scrap

A novel process of preparing cobalt, tungsten, and tungsten carbide powders from cemented carbide scrap by molten salt electrolysis has been investigated in this paper. In this experiment, WC-6Co and NaCl–KCl salt were used as sacrificial anode and electrolyte, respectively. The dissolution potential of cobalt and WC was determined by linear sweep voltammetry to be 0 and 0.6 V (vs Ag/AgCl), respectively. Furthermore, the electrochemical behavior of cobalt and tungsten ions was investigated by a variety of electrochemical techniques. Results of cyclic voltammetry (CV) and square-wave voltammetry show that the cobalt and tungsten ions existed as Co2+ and W2+ on melts, respectively. The effect of applied voltage, electrolysis current, and electrolysis times on the composition of the product was studied. Results showed that pure cobalt powder can be obtained when the electrolysis potential is lower than 0.6 V or during low current and short times. Double-cathode and two-stage electrolysis was utilized for the preparation of cobalt, tungsten carbide, and tungsten powders. Additionally, X-ray diffraction results confirm that the product collected at cathodes 1 and 2 is pure Co and WC, respectively. Pure tungsten powder was obtained after electrolysis of the second part. Scanning electron microscope results show that the diameters of tungsten, tungsten carbide, and cobalt powder are smaller than 100, 200, and 200 nm, respectively.