51 results about "Linear sweep voltammetry" patented technology

The invention relates to a preparation method of a novel nano carbon material and an electrocatalytic hydrogen production application of the novel nano carbon material. The preparation method comprises the following steps that (1), a second or multiple metal synthesized bimetal or multiple metal base ZIFs material is introduced into a monometal ZIFs skeleton structure at a special temperature; (2), the ZIFs material is carbonized in an inert atmosphere at a temperature higher than a decomposition temperature of an organic ligand of the ZIFs material to obtain a carbon material; (3), the carbon material is modified on the surface of an electrode and linear sweep voltammetry response is performed in an electrolyte solution with certain PH (potential of hydrogen) and certain concentration; (4), alternating current impedance is performed in the electrolyte solution with the certain PH and the certain concentration; (5), cyclic voltammetry response is performed in an alkaline solution and then linear sweep voltammetry response is measured. The preparation method has the benefits that a raw metal salt material is wide in range, so that the cost is saved and industrial production and preparation is facilitated; the method has important significances and wide application prospects in the aspect of the prepared nano carbon material, in an application extending the ZIFs material and in the field of electrocatalysis.

The invention provides a preparation method of a flexible electrode based on graphene. The preparation method comprises the steps of graphene oxide solution preparation, coating, chemical reduction and electrochemical reduction. In the chemical reduction step, acetic acid and hydroiodic acid are adopted as reducing agents so that the functional groups of the graphite (graphene) oxide can be well removed and the electrical conductivity of the graphene oxide can be improved; in the electrochemical reduction, pressurization is realized by virtue of linear sweep voltammetry to further reducing the oxygen-containing functional groups. The flexible thin-film electrode which is prepared by use of the preparation method of the flexible thin-film electrode and hybridized with the heat-treated graphene oxide and an electrode active material can be widely applied to the fields of batteries, touch screens, OLEDs, super capacitance materials, green and environment-friendly automobiles and the like.

The invention relates to an electrochemical reduction-oxidation graphene modified electrode and application thereof in detection of heavy metal sexivalent chromium ions in water thereof. The modifiedelectrode is prepared by directly depositing electrochemical reduction-oxidation graphene on the surface of a working electrode. The sexivalent chromium ions are detected by using chronoamperometry, linear sweep voltammetry or cyclic voltammetry, the graphene modified electrode serves as a working electrode, an Ag/AgCl electrode serves as a reference electrode, a platinum electrode serves as the counter electrode, and experimental parameter setting is detected. The graphene modified gold electrode serves as the working electrode, the electrode preparation process is simple and convenient, andthe prepared electrode has high electrochemical activity, is capable of realizing rapid detection Cr (VI), wide in detection range (5-2000ug/L) and low in lower limit of detection (0.5 ug/L), has theadvantages of resistance to interference of other metal ions, stability, short detection cycle and the like, and is expected to be applied to actual portable detection application in future.

The invention provides an electrochemical detection method for catalytic silver deposit of reducing type oxidized graphene, as well as applications thereof. The method comprises the following steps: modifying a DNA probe, which can be identified specifically by a to-be-detected object, on a gold electrode, to obtain a working electrode; reacting the working electrode, the to-be-detected object with known specific activity, and standard sample solution of substances capable of cutting the DNA probe, which can be identified specifically by a to-be-detected object, into oligonucleotides single chains, loading the reacted electrode with reducing type oxidized graphene, performing silver deposit reaction together with silver ion-containing solution, dissolving out silver monomer deposited on the working electrode, determining the dissolution volt-ampere current value by utilizing a linear sweep voltammetry, and drawing a standard cure; according to the standard cure, calculating to obtain the specific activity of the to-be-detected sample. The established electrochemical detection method has the advantages of being labeling-free, safe for detection process, simple to operate, easy to miniature, wide to apply and the like.

A method of using a graphite electrode to measure a concentration of glucose or methionine from a biological sample is described. A mechanical pencil lead may be used, as the graphite electrode, and the biological sample may come from a patient's serum. The glucose or methionine may produce a peak current response within a range of 0.4-0.8 V when the sample is subjected to linear scan voltammetry.

The invention relates to a preparation method and the application method of noble metal loaded nitrogen-doped bacterial cellulose. The method comprises the following steps: soaking bacterial celluloseinto a hydrochloric acid solution, adding aniline while stirring and performing reaction for several hours; gradually adding hydrochloric acid, in which ammonium persulfate is dissolved, into a beaker dropwise, and stirring; washing the bacterial cellulose after the reaction, and performing freeze drying; calcining the bacterial cellulose into nitrogen for several hours to obtain nitrogen doped bacterial cellulose; dispersing the nitrogen doped bacterial cellulose into a mixed solution of deionized water, ethanol and perfluorosulfonic acid, performing ultrasonic treatment uniformly, drippingon a glassy carbon electrode, and drying at a room temperature to obtain a nitrogen-doped bacterial cellulose modified electrode; depositing the electrode in hydrochloric acid liquid of chloroplatinicacid under constant potential to obtain a platinum nanoparticle loaded nitrogen-doped bacterial cellulose modified electrode; soaking the electrode into a sulfuric acid solution; inspecting the hydrogen evolution activity of the electrode by a linear scanning voltammetry, wherein the result proves that the composite has high electrolytic waster hydrogen evolution performance.

The invention discloses a method of preparing self-supporting photo-anode based on cadmium sulfide/ nickel sulfide/ nickelic sulfide ternary composites and is applied to photoelectrochemical decomposition of oxygen-making catalyst in water. The invention synthetizes the composite of cadmium sulfide/ nickel sulfide/ nickelic sulfide mainly by means of one-step hydrothermal method, can be used directly as a photo-anode after ethanol cleaning and nitrogen drying. The invention is mainly applied to photoelectrochemical water decomposition. A linear sweep voltammetry (polarization curve) is adopted to test the degree of catalytic activity of the composite of cadmium sulfide/ nickel sulfide/ nickelic sulfide. A current and voltage curve is used to test the stability of the composite of cadmium sulfide/ nickel sulfide/ nickelic sulfide in the light. According to the invention, the synergistic effect of a cadmium sulfide, two sulfides of nickel in cadmium sulfide / nickel sulfide / nickel trioxide is fully utilized and the stability of cadmium sulfide in photoelectrochemical decomposition water is improved, and the invention facilitates the continuous decomposition of water by the catalyst after a long period of time.

The invention discloses a method for electrochemical detection of total urushiol content of raw lacquer. The method is characterized in that a carbon paste electrode is used as a working electrode; the carbon paste electrode, a saturated calomel electrode and a platinum wire electrode compose a three-electrode system; and total urushiol content of raw lacquer is detected by a cyclic voltammetry or a linear sweep voltammetry. Urushiol is a derivative of catechol and produces a pair of oxidation and deoxidization peaks in a NaOH solution having a pH value of 12.0 on the carbon paste electrode, and oxidation peak current values are proportional to urushiol concentrations in a certain range. The method can be used for direct detection of total urushiol content of raw lacquer and has the advantages of high sensitivity, good selectivity, fast analysis rate and low instrument price.

The invention relates to a preparation method of Ni-W-P graded alloy. The preparation method is characterized in that an electrolyte of the Ni-W-P alloy comprises the following components according to concentrations: 20-100 g/L of nickel salt, 10-60 g/L of tungstate, 30-60 g/L of conducting salt, 15-40g/L of a dispersing agent, 10-30 g/L of citric acid, 5-40 g/L of phosphorous acid and 10-30 g/L of boric acid; the preparation method comprises the following steps: immersing workpieces after pretreatment in the electrolyte of 45-75 DEG C, adopting the linear sweep voltammetry or cyclic linear sweep voltammetry for scanning at the speed of 0.1-100 mV/s within the range from minus 1.3 V to minus 0.5 V, and adjusting the sedimentary dynamic states of different ions by adjusting the deposition potential, so as to obtain the Ni-W-P graded alloy. According to the preparation method of the Ni-W-P graded alloy, the Ni-W-P graded alloy coating prepared by adopting the preparation method has a single-layer or multi-layer graded structure and contains amorphous phases, the microhardness can reach 500-1150 Hv, the corrosion resistance and wear resistance of the coating are obviously improved, and the preparation method has a potential application prospect.

The invention provides a method for measuring the antioxidant content in a lubricating oil by use of linear sweep voltammetry, and belongs to the technical field of electrochemical detection. The method comprises the following steps: adding an ethanol solution of which the antioxidant concentration is known to an electrolyte, measuring by use of the linear sweep voltammetry to obtain the characteristic voltage-current curve of the electrolyte, calculating the characteristic peak area of the curve, establishing a working curve of the antioxidant concentration and the characteristic peak area, extracting new lubricating oil with the known antioxidant content and lubricating oil with unknown antioxidant content by using ethanol, adding the supernatant liquid to the electrolyte, measuring by use of the linear sweep voltammetry to obtain the characteristic voltage-current curve of the electrolyte, calculating the characteristic peak area of the curve, and substituting the characteristic peak area of the known antioxidant into the working curve to obtain the correction coefficient of the lubricating oil of the antioxidant to obtain the unknown antioxidant content. The method is simple, convenient and quick to operate, and high in sensitivity, and can be widely applied to the measurement of the antioxidant content in synthetic oil or mineral oil lubricating oil and the rapid evaluation of the oxidative stability of the lubricating oil.

The invention relates to a constant temperature reaction-based method for detecting microRNA in a solution to be detected. The method comprises that an electrode is immersed in a first DNA fragment molecular solution, undergoes a reaction at a temperature of 37 DEG C for 6h, then is immersed in a mercapto hexanol solution, undergoes a reaction for 1h, then is immersed in a silver nanoparticle solution, undergoes a reaction for 1h, then is immersed in a second DNA fragment molecular solution and undergoes a reaction for 0.5h, a microRNA standard liquid is prepared, the electrode is immersed in the microRNA standard liquid, a third DNA fragment molecule, a Klenow fragment and dNTPs are added into the microRNA standard liquid, the electrode undergoes a reaction in the mixed liquid at a temperature of 37 DEG C for 1h, then is immersed in a Nt. BbvCI solution and undergoes a reaction for 1h, wherein in the detection, a linear scanning voltammetry method is used, a standard curve graph is drawn, an electrical signal of the liquid to be detected is acquired by the above processes, and the electrical signal and the standard curve graph are compared so that a microRNA concentration of the liquid to be detected is obtained. The constant temperature reaction-based method has the advantages of simple processes, high sensitivity, good specificity, low background signal and wide application range.

The invention provides an NiO/Ni catalyst and a preparation method and application thereof. Oxidized NiO and reduced Ni of foam Ni adhere to foam Ni through a linear sweep voltammetry and a linear cyclic voltammetry, the NiO/Ni catalyst is formed, and the NiO/Ni catalyst has good electrical conductivity in a three-electrode system and an alkaline solution condition and can effectively catalyze methane. According to the NiO/Ni catalyst and the preparation method and application thereof, under a constant potential, the NiO/Ni catalyst can be utilized to effectively electrocatalyse methane, catalytic oxidation products of methane are carbon monoxide, methyl alcohol and ethyl alcohol, and particularly, forming of ethyl alcohol has important economic value for utilization of methane.

The invention discloses an electrochemical immunosensor electric signal marker for prostate specific antigen detection. The electric signal marker is protease, and a catalytic substrate of the protease is polypeptide with the sequence characteristic that the third amino acid from a cleavage site to a carbon end is histidine H. A detection method for prostate specific antigen detection adopts the electrochemical immunosensor electric signal marker for prostate specific antigen detection. The method comprises the steps as follows: A, preparing a secondary antibody/carbon nanotube/protease compound; B, preparing a working electrode; C, soaking the working electrode in a PBS solution containing copper ions and the polypeptide substrate for 2 h, and conducting an electrochemical test with linear sweep voltammetry. The electrical signal marker has obvious electrical signals, can meet the requirement of detection of concentration of prostate specific antigens in human serum and is harmless toworkers and environments due to the fact that no biphenyl substances are used in the catalytic substrate.

The invention discloses a method for assisted determination for an unknown arsenic form in wastewater based on an electrochemistry system. The method comprises the following steps: (1) establishing a three-electrode system: taking a gold electrode or a platinum electrode as a working electrode, taking a glassy carbon electrode as a counter electrode, and taking a saturated calomel electrode as a reference electrode; (2) preparing an experiment solution : using a sodium sulphate solution or a sulfuric acid solution as a supporting electrolyte to prepare the experiment solution, and using sodium arsenite, sodium arsenate, sodium carbonate and ferric sulfate to prepare an As (III)-CO32-(HCO3-) solution, an As (III)-Fe (III) solution and an As (V)-Fe (III) solution; (3) carrying out linear scanning detection. Based on the oxidation-reduction reaction and electrochemical principle of arsenic, the method adopts the linear scanning voltammetry of the three-electrode system to capture the change of a corresponding oxidation reduction potential when the arsenic form is changed, thereby predicting the unknown arsenic form in the wastewater containing arsenic. The method implements regulation and controlling for grasping the existing form of arsenic in the wastewater and provides methodology support for realization of deep purification.

The invention discloses an electrochemical gaging method for the content of metal vanadium in crude oil. According to the electrochemical gaging method, a carbon nano tube (CNT) paste electrode is adopted as a working electrode, H2SO4 (sulfuric acid) with pH value being 2.70 and containing 4-(2-pyridine azo)-resorcinol (PAR) and potassium bromate (KBrO3) is adopted as a base solution, a cyclic voltammetry or a linear sweep voltammetry is adopted to measure the content of vanadium in the crude oil and a crude oil sample is prepared into a sample solution after being oxidized and burned at high temperature; due to the strong adsorptive capacity of CNT, the sample does not need to be conducted for preenrichment while electrochemically gaging; according to the electrochemical gaging method, a complex is generated by the ions of the metal vanadium (V) and PAR at first, the catalytic reduction waves are produced on a surface of the CNT paste electrode by the complex in the presence of KBrO3, so that the measuring sensibility is improved; and the method has the advantages of high sensibility, good selectivity, fast analysis speed and cheap price of instruments and equipments.

The invention discloses a preparation method for a dual-signal electrochemical sensor for rapidly and selectively detecting sunset yellow, which belongs to the field of electrochemical sensors. The method comprises steps of (1) preparation of a PEI-GAs@AuNPs/SH-beta-CD composite, (2) preparation of a PEI-GAs@AuNPs/SH-beta-CD composite electrode and (3) detection by using linear sweep voltammetry.The interference of a false positive or negative result of the single signal electrochemical sensor and background current interference signals can be overcome, the food additive sunset yellow can also be detected efficiently and sensitively, and the sensitivity and the accuracy are improved.

The invention relates to a redox catalyst, in particular to a Pt/WO3-CNTs (carbon nanotubes) catalyst prepared with a hydro-thermal synthesis method. WO3-CNTs are prepared with a water bath method and the hydro-thermal synthesis method, then the supported Pt/WO3-CNTs catalyst is prepared with a microwave-assisted polyol method, and the redox performance of the catalyst is studied. Meanwhile, the influence of different WO3 contents prepared with the hydro-thermal synthesis method on the electro-catalytic property of the Pt/WO3-CNTs catalyst is studied. The study is focused on the catalytic performance of the redox of the catalyst with CV (cyclic voltammetry), LSV (linear sweep voltammetry) and other methods. Excellent physicochemical properties and electrochemical activities indicate that the novel Pt/WO3-CNTs catalyst is a most promising catalyst for advanced fuel cells.

The invention discloses a method for representing and calibrating electroplating solution exchange current density i0 and cathode transfer coefficient alpha c. By adopting linear sweep voltammetry measurement, the invention also provides a method for representing and calibrating TSV electroplating additive diffusion coefficient; by adopting chronoamperometry testing, the simple testing method is designed by using an electrochemical workstation, so that electroplating solution exchange current density, cathode transfer coefficient and additive diffusion coefficient are obtained conveniently andeffectively.