High selectivity water-soluble ammonia-nitrogen special detection sensor probe
By using a highly selective water-soluble ammonia nitrogen detection sensor probe based on catalytic reaction, and utilizing an ammonium ion selectively permeable membrane to isolate it from the environment, combined with a three-electrode system, the problems of traditional ammonia nitrogen sensors being susceptible to environmental interference and having low sensitivity are solved, thus achieving highly sensitive ammonia nitrogen detection.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- JILIN UNIVERSITY
- Filing Date
- 2025-06-11
- Publication Date
- 2026-06-19
AI Technical Summary
Traditional ammonia nitrogen sensors are susceptible to environmental factors, have low sensitivity, and are difficult to accurately monitor low concentrations of ammonia nitrogen.
A highly selective water-soluble ammonia nitrogen detector probe based on catalytic reaction is used. It is isolated from the environment by an ammonium ion selectively permeable membrane and combined with a three-electrode system to improve detection sensitivity and resist interference.
It achieves high-sensitivity ammonia nitrogen detection in complex environments, improves anti-interference capabilities, and is suitable for real-time monitoring in complex environments.
Smart Images
Figure CN224383196U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of environmental monitoring technology, specifically relating to a highly selective water-soluble ammonia nitrogen detection sensor probe. Background Technology
[0002] Ammonia nitrogen is a common water pollutant that is physiologically toxic to aquatic organisms, leading to chronic poisoning and ultimately widespread biological mortality. Because ammonia nitrogen concentration is difficult to directly represent using physical quantities such as color and turbidity, and traditional spectrophotometric detection methods are complex and costly, their widespread application is limited. Electrochemical methods, utilizing sensitive probes to directly detect ammonia nitrogen concentration in water, offer advantages such as speed, simplicity, low cost, and portability, making them highly promising for future applications.
[0003] Traditional ammonia nitrogen sensitive probes use potentiometric detection, which is susceptible to false alarms due to various environmental factors. Furthermore, their low sensitivity makes them unsuitable for monitoring low concentrations of ammonia nitrogen. In contrast, ammonia nitrogen detection probes based on specific catalytic reactions, coupled with effective probe protection measures, can effectively resist external environmental interference and provide higher sensitivity, enabling real-time and accurate monitoring of ammonia nitrogen concentrations in water environments. Utility Model Content
[0004] The purpose of this invention is to provide a highly selective water-soluble ammonia nitrogen detection sensor probe. Based on a catalytic reaction, this probe uses a selectively permeable membrane to isolate the buffer solution from the environment, avoiding the influence of other ions in the detection environment. This approach not only significantly improves the sensitivity of ammonia nitrogen detection but also enhances the probe's anti-interference capabilities, enabling it to detect ammonia nitrogen in complex environments.
[0005] The present invention discloses a high-selectivity water-soluble ammonia nitrogen detection sensor probe, which is based on a three-electrode system and consists of a protective cover 30, a main body 10, an ammonium ion selective permeable membrane assembly 20, and a handle 40. The main body 10 consists of an electrolytic cell shell 11, a working electrode 12, a reference electrode 13, a counter electrode 14, and electrode leads 15. The working electrode 12, the reference electrode 13, and the counter electrode 14 form a three-electrode system.
[0006] The electrolytic cell shell 11 has a cylindrical structure, and an electrolytic cell 16 for holding electrolyte is provided on its upper part. The electrolytic cell 16 has a concave structure of cuboid or cylinder. A working electrode 12 and a reference electrode 13 are fixed on one side wall inside the electrolytic cell, and a counter electrode 14 is fixed on the opposite side wall. The working electrode 12, the reference electrode 13, and the counter electrode 14 are led out from the lower part of the electrolytic cell shell 11 through mutually insulated electrode leads 15. The lower part of the electrolytic cell shell 11 is sealed and insulated and waterproof.
[0007] The ammonium ion selective permeation membrane assembly 20 consists of an ammonium ion selective permeation membrane 21 and a ring-shaped support structure 22. The ammonium ion selective permeation membrane 21 is disposed on the upper surface of the ring-shaped support structure 22. The ammonium ion selective permeation membrane 21 allows ammonium ions in water to pass through and filters out most interfering molecules and ions. The selective ion permeation membrane is usually a cation exchange membrane manufactured by Nafion.
[0008] The protective cover 30 can be installed on the outside of the annular support structure 22 by snap-fit or thread to prevent dust and collision friction when the probe is not in operation.
[0009] The ammonium ion selective permeable membrane assembly 20 is installed on the outer side of the upper part of the electrolytic cell shell 11 by snap-fit or thread, forming a waterproof and sealed structure with the electrolytic cell 16; the electrolytic cell 16 is filled with an alkaline electrolyte with pH=12 to 14; the electrolyte can usually be a potassium hydroxide or sodium hydroxide solution.
[0010] The electrolytic cell housing 11 is connected to the handle 40 by threads, and the electrode lead 15 is sealed inside the handle 40 and leads out from the tail of the handle 40; the handle 40 is sealed and insulated and waterproof.
[0011] The protective cover 30, the electrolytic cell housing 11, the support structure 22, and the handle 40 have the same outer diameter, which is convenient for the user to hold.
[0012] In the prior art, ammonium ion selective electrodes detect ammonium ions by utilizing the potential change caused by the adsorption of ammonium ions by the electrode, which has poor selectivity for similar cations. However, this invention adopts a catalytic mechanism, which is not affected by the interference of anions and cations, thus solving the problems of poor anti-interference and low detection sensitivity of existing water-soluble ammonia nitrogen sensor probes. In addition, this invention encapsulates the three-electrode system, improving the problem of its direct exposure to the outside and easy collision and friction with external objects. Attached Figure Description
[0013] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0014] Figure 1 This is a schematic diagram of the overall structure of the device before assembly.
[0015] Figure 2 This is a schematic diagram of the structure of the ammonium ion selectively permeable membrane in the device described in this utility model;
[0016] Figure 3a and Figure 3b This is a schematic diagram of the main body of the device described in this utility model;
[0017] Figure 4 This is a schematic diagram of the combined structure of the main body and the ammonium ion selectively permeable membrane in the device described in this utility model;
[0018] Figure 5 This is a schematic diagram of the overall structure of the device after assembly.
[0019] Figure 6(a) shows the differential pulse voltammetry (DPV) curves of Pt-Zn nanoalloy modified carbon cloth electrode in 1 mol / L KOH solution for 1 μM to 1000 μM NH4Cl. Figure 6(b) shows the linear fitting relationship between the peak current of the DPV curve relative to the reversible hydrogen electrode, i.e., near 0.53 V of RHE, and the concentration of NH4Cl.
[0020] The names of each part are: main body 10, electrolytic cell shell 11, electrode lead 15, working electrode 12, reference electrode 13, counter electrode 14, electrolytic cell 16, ammonium ion selective permeable membrane assembly 20, selective ion permeable membrane 21, support structure 22, protective cover 30 and handle 40. Detailed Implementation
[0021] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.
[0022] Obviously, the described embodiments are only a part of the implementation of this utility model, and not all of the embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
[0023] Example 1
[0024] like Figures 1-5 As shown, the high-selectivity water-soluble ammonia nitrogen detection sensor probe of this utility model is based on a three-electrode system, consisting of a protective cover 30, a main body 10, an ammonium ion selective permeable membrane assembly 20, and a handle 40; the main body 10 consists of an electrolytic cell shell 11, a working electrode 12, a reference electrode 13, a counter electrode 14, and electrode leads 15; the working electrode 12, the reference electrode 13, and the counter electrode 14 form a three-electrode system.
[0025] The electrolytic cell shell 11 has a cylindrical structure, and an electrolytic cell 16 for holding electrolyte is provided on its upper part. The electrolytic cell 16 has a concave structure of cuboid or cylinder. A working electrode 12 and a reference electrode 13 are fixed on one side wall inside the electrolytic cell, and a counter electrode 14 is fixed on the opposite side wall. The working electrode 12, the reference electrode 13, and the counter electrode 14 are led out from the lower part of the electrolytic cell shell 11 through mutually insulated electrode leads 15. The lower part of the electrolytic cell shell 11 is sealed and insulated and waterproof.
[0026] The ammonium ion selective permeation membrane assembly 20 consists of an ammonium ion selective permeation membrane 21 and a ring-shaped support structure 22. The selective ion permeation membrane 21 is disposed on the upper surface of the ring-shaped support structure 22. The ammonium ion selective permeation membrane 21 allows ammonium ions in water to pass through and filters out most interfering molecules and ions. The selective ion permeation membrane is usually a cation exchange membrane manufactured by Nafion.
[0027] The protective cover 30 can be installed on the outside of the annular support structure 2 by snap-fit or thread to prevent dust and collision friction when the probe is not in operation.
[0028] The ammonium ion selective permeable membrane assembly 20 is installed on the outer side of the upper part of the electrolytic cell housing 11 by snap-fit or thread, forming a waterproof and sealed structure with the electrolytic cell 16; the electrolytic cell 16 is filled with an alkaline electrolyte with pH=12-14, which can usually be a potassium hydroxide or sodium hydroxide solution; the electrolytic cell housing 11 is connected to the handle 40 by thread, and the electrode lead 15 is sealed inside the handle 40 and leads out from the tail of the handle 40; the handle 40 is sealed and insulated and waterproof.
[0029] The protective cover 30, the electrolytic cell housing 11, the support structure 22, and the handle 40 have the same outer diameter.
[0030] The electrolytic cell shell 11 is made of polytetrafluoroethylene. The upper electrolytic cell 16 has a rectangular concave structure with dimensions of 1.5cm × 1.5cm × 1.2cm. The working electrode 12 is a Pt-Zn nano-alloy modified carbon cloth electrode prepared by electrodeposition (Wang, G.;Zhou, G.;Zhang, Q.;He, D.;Zhao, C.;Suo, H.Sensitive Electrochemical Detection of Ammonia Nitrogen via aPlatinum–Zinc AlloyNanoflower-Modified Carbon Cloth Electrode.Sensors 2024, 24, 915.https: / / doi.org / 10.3390 / s24030915), with dimensions of 1cm × 1cm, and is fixed to the side wall of the electrolytic cell 16 with waterproof adhesive.
[0031] The reference electrode 13 is a high-purity zinc rod, which is fixed to the side wall of the electrolytic cell 16 on the same side as the working electrode 12 with waterproof adhesive.
[0032] The counter electrode 14 is a platinum-plated high-purity copper sheet, measuring 1cm × 1cm, and is fixed to the side wall of the electrolytic cell 16 opposite the working electrode 12 with waterproof adhesive.
[0033] The support structure 22 of the ammonium ion selective permeable membrane assembly 20 is made of polytetrafluoroethylene and is installed on the outer side of the upper part of the electrolytic cell housing 11 by snap-fit or thread, and forms a waterproof seal structure between the membrane assembly and the electrolytic cell 16 by waterproof adhesive.
[0034] The electrolytic cell 16 is filled with a 1 mol / L KOH solution with a pH of 14.
[0035] Working principle: Remove the protective cover 30, place the ammonium ion selective permeation membrane assembly 20 of the special detection sensor probe into the aqueous solution of ammonia nitrogen to be detected. The ammonium ions in the aqueous solution pass through the selective ion permeation membrane 21 into the KOH solution of the electrolytic cell 16, and react with OH-. - Ions combine to form NH3·H2O. Since NH3 is adsorbed on the electrode surface in an anionic manner, and the main interfering substances are organic molecules or organic anions such as hydrazine hydrate, urea, and glucose, and the cation exchange membrane only allows cations such as ammonium to pass through, this membrane can effectively filter out interfering ions and molecules, ensuring detection selectivity.
[0036] When a voltage is applied, NH3 oxidizes on the surface of the carbon cloth electrode, generating a corresponding current that can be used as a sensor signal input. The three electrodes are connected via leads to an electrochemical workstation or an integrated circuit with potentiostat and signal generator functions, enabling cyclic voltammetry (CV) scans (typically 0-1V vs RHE.) or differential pulse voltammetry (DPV) tests (typically 0.4V-0.8V).
[0037] DPV tests were performed using NH4Cl standard solutions of different concentrations (10 μM, 20 μM, 30 μM, 40 μM, 50 μM, 60 μM, 70 μM, 80 μM, 90 μM, 100 μM, 200 μM, 300 μM, 400 μM, 500 μM, 1000 μM), and the current peak response near 0.53 V (vs. RHE) was read to calibrate the concentration-current curve relationship. Figure 6(a) shows the response curve of the working electrode to 1 μM–1000 μM NH4Cl in potassium hydroxide solution at pH 14, and Figure 6(b) shows the linear fitting relationship between concentration and current. This can then be used to detect the ammonia nitrogen concentration in actual samples; the corresponding concentration value can be calculated by substituting the measured current response into the concentration-current curve.
[0038] For example, the linear relationship of the DPV curve measured in the range of 10μM to 100μM is y = 0.00665x + 2.040 (mA / cm). 2 If the measured current density in the solution is 2.50 mA / cm², then... 2 At that time, the NH4 in the solution + The concentration was 69.17 μM.
[0039] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0040] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above description is only a specific embodiment of this utility model and is not intended to limit this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.
Claims
1. A highly selective water-soluble ammonia nitrogen detection sensor probe, characterized in that: It consists of a protective cover (30), a main body (10), an ammonium ion selective permeable membrane assembly (20), and a handle (40); The main body (10) consists of an electrolytic cell shell (11), a working electrode (12), a reference electrode (13), a counter electrode (14), and electrode leads (15). The working electrode (12), the reference electrode (13), and the counter electrode (14) form a three-electrode system. The electrolytic cell shell (11) is a cylindrical structure with an electrolytic cell (16) for holding electrolyte on its upper part. The electrolytic cell (16) is a cuboid or cylindrical concave structure. The working electrode (12) and the reference electrode (13) are fixed on one side wall of the electrolytic cell, and the counter electrode (14) is fixed on the opposite side wall. The working electrode (12), the reference electrode (13), and the counter electrode (14) are led out from the lower part of the electrolytic cell shell (11) through mutually insulated electrode leads (15). The lower part of the electrolytic cell shell (11) is sealed and insulated from water. The ammonium ion selective permeable membrane assembly (20) consists of an ammonium ion selective permeable membrane (21) and a ring support structure (22), with the ammonium ion selective permeable membrane (21) disposed on the upper surface of the ring support structure (22). The protective cover (30) is installed on the outside of the annular support structure (22) by a snap or thread; The ammonium ion selective permeable membrane assembly (20) is installed on the outer side of the upper part of the electrolytic cell shell (11) by snap-fit or thread to form a waterproof seal between it and the electrolytic cell (16); the electrolytic cell (16) is filled with an alkaline electrolyte with pH = 12 to 14; The electrolytic cell shell (11) is connected to the handle (40) by threads, and the electrode lead (15) is sealed inside the handle (40) and leads out from the tail of the handle (40); the handle (40) is sealed and insulated and waterproof.
2. The highly selective water-soluble ammonia nitrogen detection sensor probe as described in claim 1, characterized in that: The protective cover (30), the electrolytic cell housing (11), the support structure (22) and the handle (40) have the same outer diameter, making them easy for users to hold.
3. The highly selective water-soluble ammonia nitrogen detection sensor probe as described in claim 1, characterized in that: The ammonium ion selective ion permeation membrane (21) is a cation exchange membrane manufactured by Nafion.
4. The highly selective water-soluble ammonia nitrogen detection sensor probe as described in claim 1, characterized in that: The electrolyte is a potassium hydroxide or sodium hydroxide solution.