426results about "Cobalt oxides/hydroxides" patented technology

The invention relates to the field of gas sensors, and discloses a hydrogen sulfide gas sensor and a method for detecting the concentration of hydrogen sulfide in gas. The hydrogen sulfide gas sensor comprises a substrate and a gas sensitive material, a cavity is formed in the substrate, the gas-sensitive material is located above the cavity, and the two ends of the gas-sensitive material are connected with the gold electrodes on the substrate; the gas sensitive material comprises graphene fiber and metal oxide loaded on the graphene fiber. The metal oxide is selected from one or more than two of oxides of Zn, Cd, Cu, Ni, Pd, Pt, Co, Ir, Fe, Mn, Cr, Mo, W, V, Ti, Mg and Al; the specific surface area of the gas sensitive material is 80-150m < 2 > / g; the loading capacity of the metal oxide is 0.05 to 5 weight percent. The hydrogen sulfide gas sensor can be self-heated, has high sensitivity to hydrogen sulfide gas, and is suitable for being applied to the field of gas monitoring.

The invention relates to a NiCoW-CoP / Co3O4 (at) NF self-supporting heterostructure catalyst and a preparation method thereof. The preparation method comprises the following steps: preparing a CoP-coated NF precursor on foamed nickel through a constant potential electrodeposition method, then carrying out annealing treatment in a muffle furnace, and finally carrying out electrodeposition on NiCoW-LDH to obtain the NiCoW-CoP / Co3O4-coated NF material. According to the preparation method, the microsphere material with the surface covered with the dendritic dendrites is synthesized, and exposure of active sites is increased through the special surface structure of the microsphere material. The compounding of the trimetal hydroxide containing high-valence tungsten and the introduction of oxygen vacancies can effectively enhance the local electron density of oxygen atoms on the surface of the catalyst, thereby enhancing the catalytic performance and seawater corrosion resistance of the material. Compared with the prior art, the method disclosed by the invention is simple to operate and low in cost, and the prepared catalyst has high electrocatalytic activity, relatively low hydrogen evolution overpotential and oxygen evolution overpotential and long-time stability. And the method has important theoretical significance and potential application value for developing a bifunctional electrocatalyst suitable for electrolyzing seawater.

The invention discloses a preparation method of a metal-doped cobalt-based oxide material, which comprises the following steps: metal nitrate is dissolved in glycerol and isopropanol, a solvothermal method is adopted for reaction to obtain a reaction product, the metal in the metal nitrate comprises cobalt and at least one of nickel, copper, iron or molybdenum, the concentration of cobalt nitrate in the dissolved solution is 0.001-0.05 mM, and the concentration of cobalt nitrate in the solution is 0.01-0.05 mM; the concentration of metal nitrate except cobalt is 0.1-1 mu M; the reaction product is subjected to high-temperature calcination, the metal-doped cobalt-based oxide material with the microstructure being nanospheres with rough surfaces is obtained, the reaction temperature of the solvothermal method is 120-180 DEG C, and the reaction time is 3-6 h. The invention also discloses the metal element doped cobalt-based oxide material obtained by the preparation method and application of the metal element doped cobalt-based oxide material in electrocatalytic nitrate reduction synthesis of ammonia. The preparation method provided by the invention is simple, and the prepared metal-doped cobalt-based oxide material shows excellent electrochemical performance when applied to electrocatalytic nitrate reduction synthesis of ammonia.

The invention discloses a cobaltosic oxide catalyst doped with lanthanide metal, a preparation method of the cobaltosic oxide catalyst and application of the cobaltosic oxide catalyst to ammonia production through nitrate reduction. The method comprises the following steps: carrying out hydrothermal reaction on cobalt nitrate hexahydrate and a lanthanide metal salt precursor in a mixed system of isopropanol and glycerol, and then carrying out high-temperature calcination to prepare the lanthanide metal-doped cobaltosic oxide catalyst. The preparation method disclosed by the invention is simple to operate and low in cost, the prepared lanthanide metal-doped cobaltosic oxide catalyst shows excellent Faraday efficiency, ammonia yield and cycling stability in an electro-catalysis nitrate reduction reaction, a traditional path of preparing ammonia from nitrate is broken through, and more efficient performance is realized.

The invention relates to a coprecipitation method for preparing cobaltosic oxide, which comprises the following steps: mixing a cobalt salt solution, a precipitant solution and a complexing agent solution in a carbonate base solution in a parallel flow manner, and carrying out first coprecipitation reaction to a first particle size to obtain a seed crystal; the cobalt salt solution, the precipitant solution and the complexing agent solution are mixed in a parallel flow mode, a second coprecipitation reaction is conducted, and cobalt carbonate powder is obtained; calcining the cobalt carbonate powder to obtain cobaltosic oxide with a median particle size D50 of 18-20 [mu] m; a complexing agent in the complexing agent solution is iminodiacetic acid. According to the invention, by using the specific complexing agent, cobalt ions exist in the system in the form of complex ions and are slowly released in the reaction process, so that the first coprecipitation reaction can be carried out orderly, and the cobaltosic oxide with the median particle size D50 of 18-20 [mu] m can be obtained.

The present application belongs to the field of new energy, and discloses a waste lithium ion battery crushing, sorting, and recycling method, comprising the following steps: step 1, crushing a lithium ion battery and heating, to obtain a first solid; step 2, removing a housing, to obtain a second solid; step 3, sieving the second solid, to obtain a first undersize product and a first oversize product; step 4, performing airflow sorting on the first oversize product to remove a separator, to obtain a third solid; step 5, pyrolyzing the first undersize product and the third solid, to obtain a fourth solid; step 6, sieving the fourth solid, to obtain a second undersize product and a second oversize product; and step 7, crushing and sieving the second oversize product, to obtain a third undersize product and a third oversize product. By means of collecting black powder before and after crushing in step 7, the present method implements black powder grading, thereby facilitating targeted treatment of black powder of different grades. The black powder recovery rate and the collection efficiency of the present application are high, and a separator is efficiently removed. Furthermore, the present application also discloses a system suitable for said method.

The invention provides a sulfo-spinel composite catalyst, a preparation method thereof and an electrolyzed water catalyst. The preparation method comprises the following steps: adding a carrier into a mixed solution of cobalt salt, a morphology regulator and a precipitator, carrying out hydrothermal reaction, washing and drying to obtain a cobalt precursor; the cobalt precursor is subjected to calcination treatment, and a Co3O4 catalyst is obtained; mixing the Co3O4 catalyst with a sulfur source solution, carrying out vulcanization reaction, washing and drying; and mixing a product of the sulfuration reaction with a reducing agent, carrying out reduction treatment, washing and drying to obtain the sulfo-spinel composite catalyst. The invention also provides the sulfo-spinel composite catalyst obtained by the preparation method, and an electrolyzed water catalyst containing the sulfo-spinel composite catalyst. The catalyst has relatively high OER catalytic activity and HER catalytic activity.

The present disclosure belongs to the field of batteries, and particularly relates to cobalt hydroxide and a preparation method therefor, a positive electrode material, a battery and electrical equipment. Provided in the present disclosure is cobalt hydroxide, the particles of which are in the shape of a sheet and have an average thickness of 10-20 nm. The cobalt hydroxide of the present disclosure is nanosheets having an extremely small average thickness and a larger surface area, which can thus improve the coating effect thereof on a positive electrode material, thereby effectively inhibiting the formation of a nickel oxide rock salt-like phase in the positive electrode material, reducing the concentration of residual lithium on the surface of the positive electrode material and enabling lithium ions to be quickly deintercalated / intercalated; therefore, the electrical properties of the positive electrode material prepared therefrom can be significantly improved.

The invention provides spherical cobaltosic oxide as well as a preparation method and application thereof, the preparation method comprises the following steps: (1) injecting a cobalt salt-containing solution and a carbonate solution into a base solution in a parallel flow manner for a coprecipitation reaction to obtain a mixed-phase precursor; and (2) calcining the mixed phase precursor to obtain the spherical cobaltosic oxide, wherein the solute of the base solution in the step (1) is alkali metal hydroxide. According to the method disclosed by the invention, the precursor of the hydroxyl cobalt oxide and cobalt carbonate mixed phase can be prepared without separating kettles, the content of foreign ions in the precursor is low, and small-particle and high-purity cobaltosic oxide can be prepared by directly sintering.

The present application provides a preparation method of a cobalt-coated lithium nickel manganese oxide cathode material. By means of an in-situ coprecipitation method, a trace amount of cobalt coating layer is constructed on the surface of the precursor. The interfacial stability is improved by using the electron conduction enhancement effect of cobalt, and the cobalt-free property of the material bulk is retained, so that the material has a complete crystal structure. When applied to a lithium-ion battery, it has good discharge specific capacity and cycling performance. The first-cycle discharge capacity reaches 193.52 mAh / g, and the 250-cycle retention rate reaches 90.38%. The electrochemical stability is significantly enhanced. The present application also provides a cobalt-coated lithium nickel manganese oxide cathode material and a lithium-ion battery.

The invention discloses a Co-MOF derivative-based Ni < x > Co < 3-x > O < 4 > oxygen evolution catalyst and a preparation method thereof.The preparation method comprises the steps that 2-methylimidazole and cobalt salt are added into a methanol solution, stirring reaction is performed to obtain a nano rhombic precursor Co-MOF, then the Co-MOF is dispersed into a solution containing a nickel source, stirring reaction, centrifugal washing and drying are performed to obtain Co-Ni MOF, and finally the Co-Ni MOF is calcined in the air atmosphere to obtain the Co-MOF-based Ni < x > Co < 3-x > O < 4 > oxygen evolution catalyst. The temperature is raised to 300-375 DEG C for annealing, the Ni < x > Co < 3-x > O < 4 > oxygen evolution catalyst is obtained after cold annealing, and the Ni atom fraction in the Ni < x > Co < 3-x > O < 4 > oxygen evolution catalyst is controlled to be 4%-10%.

The application discloses a method for selectively extracting metals from waste ternary lithium batteries by using a eutectic solvent. The method uses a eutectic solvent DES synthesized by choline chloride and oxalic acid as an extraction agent, quotes dimethyl sulfoxide DMSO and water as diluents, introduces a circulation and extraction step on the basis of metal element series immersion, i.e. extracts lithium oxalate from the leaching solution with ethanol and recycles the DES by fractional distillation, and makes innovations in recycling of metal lithium and recycling of the DES. The application has the advantages of high efficiency extraction, high precision purification, innovative extraction of lithium element and innovative recovery of the reagent DES.

The invention provides high-aluminum doped cobalt carbonate and a preparation method and application thereof, and the preparation method comprises the following steps: (1) injecting a cobalt-aluminum mixed salt solution, a carbonate solution and an organic weak acid solution into a base solution in a parallel flow manner, and carrying out a co-precipitation reaction to obtain a precursor; and (2) stopping injection of the organic weak acid solution, continuing to inject the cobalt-aluminum mixed salt solution and the carbonate solution, and carrying out a co-precipitation reaction to obtain the high-aluminum doped cobalt carbonate. According to the method, through segmented coprecipitation and control of the types of precipitants used for coprecipitation of all the segments, the doping amount and uniformity of aluminum in cobalt carbonate can be improved, aluminum segregation is avoided, and meanwhile high-aluminum-doped cobalt carbonate higher in sphericity degree and better in compactness can be obtained.

The invention belongs to the technical field of electronic components, and provides a xylene gas sensor based on a Co3O4 and In2O3 heterojunction, and a preparation process and application thereof. The xylene gas sensor comprises a gas sensitive material and an alumina ceramic tube, wherein the gas sensitive material is coated on the surface of the alumina ceramic tube. The gas sensitive material is a nano composite material formed by cobaltosic oxide and indium trioxide. The method is simple in production process, and the obtained gas-sensitive material shows relatively high sensitivity and rapid response and recovery to xylene. Due to the fact that a gas sensor with related achievements is too high in lower limit of detection of to-be-detected gas, the detection performance in a low-concentration environment is not ideal enough. According to the invention, the lower detection limit of the gas sensor can be greatly reduced, and the gas sensor still has obvious response under the concentration of 0.1 ppm, so that xylene in a gas environment can be timely found and protected.

The invention relates to the technical field of electrocatalysts, in particular to a ruthenium cobalt oxide self-supporting electrode and a preparation method and application thereof. A titanium mesh is used as a substrate, a hydrochloric acid aqueous solution of ruthenium chloride and cobalt chloride grows ruthenium dioxide nanoparticles in situ on the titanium mesh through a hydrothermal method, cobalt atoms are doped into ruthenium dioxide crystal lattices, and a self-supporting electrode of cobalt doped ruthenium dioxide is formed and used as an electrocatalyst for oxygen evolution reaction and hydrogen evolution reaction. A catalytic material grows in situ on a three-dimensional porous conductive substrate, a self-supporting catalyst is prepared, a binder is not needed, the specific surface area is larger, more active sites can be exposed, the activity and stability of the material are further improved, low-electronegativity cobalt provides electrons for ruthenium through adjustment of doped elements, excessive oxidation of ruthenium is inhibited, and the performance of the catalyst is improved. The activity and stability of the catalyst are improved to a certain extent, so that the catalyst has good performance under high current density, is prepared by using a hydrothermal method, is simple and controllable in process, and can be widely applied to water electrolysis devices.

The invention discloses a modified cobaltosic oxide catalyst and a preparation method and application thereof.The catalyst comprises a carrier foamed nickel, tungsten and chlorine co-doped cobaltosic oxide nanosheets W and Cl-Co3O4, the tungsten and chlorine co-doped cobaltosic oxide nanosheets W and the Cl-Co3O4 are loaded on the carrier, cobalt chloride and tungsten salt serve as precursors of the catalyst, and the tungsten and chlorine co-doped cobaltosic oxide nanosheets W and the Cl-Co3O4 are loaded on the carrier. The preparation method comprises the following steps: firstly, carrying out a hydrothermal reaction to obtain a nickel foam loaded tungsten-doped basic cobalt chloride nanosheet W-Co2 (OH) 3Cl2, and then carrying out in-situ conversion on the Co2 (OH) 3Cl2 into a nickel foam loaded tungsten and chlorine co-doped cobaltosic oxide nanosheet W, Cl-Co3O4 through calcination. According to the invention, chlorine and tungsten are introduced into cobaltosic oxide, so that the activity and stability of electrocatalytic oxygen evolution are improved, and the cobaltosic oxide is used as an anode catalyst for electrocatalytic seawater decomposition and has excellent activity and stability of electrocatalytic oxygen evolution.

The present application provides a cathode lithium supplement material, a cathode electrode sheet containing the material, and an electrochemical device. The cathode lithium supplement material includes: a matrix of xLi₂O·yM and carbon present on the matrix; wherein x > 0, 0.4x ≤ y ≤ 2x, and M includes at least one of Mn, Fe, Co, Ni, Cu, Cr, or V. The cathode lithium supplement material has strong chemical stability and can effectively improve the particle agglomeration phenomenon during the slurry mixing process. Applying the cathode lithium supplement material in the cathode electrode sheet can achieve the supplement of active lithium and effectively improve the energy density of the electrochemical device.

Disclosed in the present invention is an application of sodium thiosulfate as an auxiliary agent for nickel-cobalt precipitation. The application comprises the following steps: (1) adding sodium thiosulfate to a solution after iron and aluminum removal, and stirring at 50-65°C to obtain a nickel-cobalt precipitation stock solution; (2) adding an alkali to the nickel-cobalt precipitation stock solution, adjusting the pH of a system to 7.0-7.4, and maintaining the pH to allow for sufficient precipitation of nickel and cobalt to obtain precipitate; and (3) washing the precipitate to obtain mixed hydroxide precipitate (MHP). In the present invention, sodium thiosulfate is used as the auxiliary agent for nickel-cobalt precipitation, and the precipitation rate of nickel and cobalt from the solution after iron and aluminum removal is promoted by means of the addition of the auxiliary agent, reducing the content of manganese in MHP product. The present invention has good economic value and is easy for industrial application.

The utility model relates to the technical field of cobalt-nickel salt extraction and separation, and discloses an efficient cobalt-nickel salt extraction and separation device which comprises a support, an extraction tank is fixedly connected to the middle of the support, a transverse plate is fixedly connected to the upper portion of the extraction tank, a motor is arranged on the rear side of the outer portion of the transverse plate, and the output end of the motor is fixedly connected with a rotating disc. And a fixed rod is fixedly connected to the outer portion of the rotary disc, the fixed rod is sleeved with a reciprocating rod, guide rings are fixedly connected to the two sides of the outer portion of the transverse plate, the reciprocating rod is slidably connected to the interiors of the two guide rings, and a connecting rod is fixedly connected to the lower portion of the reciprocating rod. According to the extraction tank disclosed by the utility model, in the extraction process, the upper and lower different areas in the extraction tank can be conveniently stirred, uniform distribution of materials in the extraction tank is ensured, contact between cobalt and nickel and a leaching agent can be accelerated, and the extraction efficiency is improved while the reaction rate is improved.

The present invention discloses a MOF-derived cobalt trioxide @ cobalt oxide @ cobalt diphosphide composite material and its preparation method and application, which belongs to the technical field of MOF-derived composite materials. It includes: the present invention synthesizes Co‑MOF‑74 by a hydrothermal method, then in-situ oxidation under an air atmosphere, and then in-situ partial phosphating under an argon atmosphere, and the obtained sample is Co3O4@CoO@Co2P composite photocatalyst. The advantage of the present invention is that the composite photocatalyst prepared with rod-shaped Co‑MOF‑74 as a template inherits the regular rod-shaped morphology and porous structure of the MOF precursor, provides more contact and reaction sites for surface charge and mass transfer in the photocatalytic reaction, and promotes the migration and separation of photogenerated carriers. The preparation process of the method of the present invention is simple, the reaction conditions are suitable, it is suitable for large-scale promotion, and has good application prospects in the fields of environment, energy, etc.

The invention relates to the field of nano materials and photonic crystal materials, in particular to nano particles, preparation of the nano particles and application of the nano particles in self-assembly of three-dimensional non-close-packed photonic crystals. The nanoparticles can be self-assembled into a three-dimensional non-close-packed photonic crystal in a concentration range of 1 wt%-60 wt%. According to the invention, the problem that the self-assembly of the three-dimensional non-close-packed colloid photonic crystal is difficult to realize at low concentration at present is solved. By adjusting the mass fraction of the particles in a solution, the three-dimensional non-close-packed colloidal photonic crystal with rich colors can be formed through self-assembly, and the three-dimensional non-close-packed colloidal photonic crystal has wide application prospects in the fields of sensing, display and the like.

Disclosed herein are lithium-cobalt-based composite oxide particles obtained by a solid-phase process and capable of reducing the weight and thickness of a positive electrode material when used as a positive electrode active material for non-aqueous lithium secondary batteries or all-solid-state batteries and a method for producing the same. The lithium-cobalt-based composite oxide particles are formed of a lithium-cobalt-based composite oxide having an average primary particle diameter of 0.50 µm or less and show a weight loss on heating at 850°C of 1.5 mass% or less.

The present invention provides a method for comprehensively recovering lithium and cobalt from the cathode material of waste lithium cobalt oxide batteries, comprising the following steps: (1) Pretreating the cathode material of waste lithium cobalt oxide batteries to obtain lithium cobalt oxide cathode active material; mixing the lithium cobalt oxide cathode active material evenly with a sulfur-based compound and a carbon source to obtain a mixed material; subjecting the mixed material to roasting in an inert atmosphere, grinding, leaching, and filtering in sequence to obtain a lithium-containing solution and a sulfur-containing filter residue; (2) Subjecting the sulfur-containing filter residue to acid leaching for impurity removal and filtering to obtain cobalt sulfide slag; (3) Roasting the cobalt sulfide slag in an oxygen atmosphere to obtain a roasted product; (4) Subjecting the roasted product to leaching and filtering to obtain a cobalt sulfate solution and cobalt tetroxide. The method of the present invention can obtain soluble sulfates and high-purity cobalt oxides, and has a short process flow, low cost, and high lithium selectivity.

This invention belongs to the field of lithium-ion battery technology, specifically relating to a composite cathode material for lithium-ion batteries and its preparation method. The composite cathode material consists of three parts: a cathode matrix material, a lithium replenishment material, and a catalyst material. The preparation method is as follows: (1) preparing a composite material of the cathode matrix material and the lithium replenishment material in situ; (2) dispersing the catalyst material on the surface of the composite material and forming a stable interface layer between the catalyst material and the lithium replenishment material. Through the method of this invention: the lithium replenishment material has both surface modification of the cathode matrix material and lithium replenishment of the negative electrode, simultaneously improving the battery's initial efficiency and cycle stability; introducing the catalyst material onto the surface of the lithium replenishment material in situ fixes the free O generated by the Li release from the lithium replenishment material, alleviating the battery swelling phenomenon and further improving the battery's cycle stability and safety; moreover, the preparation process is simple, the raw materials are cheap and readily available, the production cost is low, and it is easy to promote industrial production.

The present invention relates to the technical field of microwave heating, and particularly relates to a zinc oxide or zinc oxide-based microwave heating material, a preparation method thereof, and an application thereof in microwave treatment of carbon-containing materials. The present invention synthesizes the microwave heating material zinc oxide by a simple method, and uses a zinc oxide matrix by screening a suitable preparation method, and constructs a zinc oxide-based composite material with a micro-nano structural morphology of needles, petals and rods by using a modifier, so as to effectively improve the microwave heating efficiency of a variety of inorganic metals or non-metallic materials with poor microwave transparency or heating effect, and realize its application in the microwave treatment process of carbon-containing materials. In addition, the method of the present invention can also realize various morphologies of the microwave heating material by adjusting the ratio and synthesis method between the components. The method of the present invention has a simple process, cheap and easily available raw materials, and is more conducive to industrial production.

The invention belongs to the field of batteries, and particularly relates to sulfur-doped cobaltosic oxide as well as a preparation method and application thereof. The sulfur-doped cobaltosic oxide is micron-sized spherical particles of which the bulk phase is uniformly doped with a sulfur element, and at least part of the sulfur element is doped into an oxygen site of a cobaltosic oxide lattice. The sulfur-doped cobaltosic oxide provided by the invention can effectively improve the gram volume and cycle performance of the lithium ion / sodium ion battery, and has a wide application prospect.

Provided is a method for separating impurities and cobalt without using an electrolysis process from a cobalt chloride solution containing impurities and producing a high purity cobalt sulfate. The production method for cobalt sulfate includes: a copper removal step (S1) of adding a sulfurizing agent to a cobalt chloride solution containing one or more impurities of copper, zinc, manganese, calcium, and magnesium and generating a precipitate of sulfide of copper to separate to remove copper; a neutralization step (S2) of adding a neutralizer or a carbonation agent to a cobalt chloride solution having undergone through the copper removal step (S1) and generating cobalt hydroxide or basic cobalt carbonate to separate magnesium; a leaching step (S3) of adding sulfuric acid to the cobalt hydroxide or the basic cobalt carbonate to obtain cobalt sulfate solution; and a solvent extraction step (S4) of bringing an organic solvent containing an alkyl phosphoric acid-based extractant to the cobalt sulfate solution and extracting zinc, manganese, and calcium into the organic solvent to separate to remove zinc, manganese, and calcium. These steps are sequentially executed.

A method for preparing a two-dimensional porous oxide belongs to the technical field of porous oxide preparation. The method includes the following steps: (1) using a metal salt as a precursor, an ion-intercalated two-dimensional oxide is prepared by a molten salt method; (2) the ion-intercalated two-dimensional oxide is mixed with a lithium initiator, reacted for a predetermined time, and then the unreacted lithium initiator is removed, filtered, and washed to obtain the two-dimensional porous oxide. The two-dimensional porous oxide prepared by this method forms uniform pores with a pore size range of 2-10 nm and a specific surface area of ​​200-300 m². 2 / g.

The present invention discloses a method for preparing highly doped aluminum cobalt oxide, comprising the following steps: preparing a mixed solution A containing a cobalt salt, an aluminum salt, and a complexing agent; the complexing agent being a mixture of a soluble sulfide and a soluble phosphate; adding the mixed solution A and an alkaline solution to a bottom solution, adjusting the pH, controlling the reaction temperature, and reacting to obtain a reactant B; filtering and washing the reactant B, performing a first calcination and subsequent washing; then performing a second calcination and screening to obtain the product. The product prepared by the method of the present invention utilizes a mixture of sulfide and phosphate as a dual complexing agent instead of an ammonia complexing agent, significantly improving the environmental pollution of the production process and effectively reducing environmental treatment costs. The prepared product has a more uniform morphology, good particle consistency, a high specific surface area, and can achieve an aluminum content of up to approximately 10,000 ppm of cobalt oxide.

The disclosure relates to methods to prepare metal oxide nanoparticles (MONs) from the cathodes of lithium-ion batteries (LIBs), and related compositions and systems. The MONs can be used to improve the properties of drilling fluids, such as those used in underground drilling methods to produce oil and / or natural gas.