阅读说明：本技术 一种电化学氨气传感器芯片及其使用方法 (Electrochemical ammonia gas sensor chip and use method thereof ) 是由 苗伟峰 徐斌 张文振 孔德方 王梦寻 于 2020-11-19 设计创作，主要内容包括：本发明公开一种电化学氨气传感器芯片,其整体为片状包括第一固体电解质层、第二固体电解质层、第三固体电解质层、第四固体电解质层和第五固体电解质层,第一固体电解质层上有开口一处和扩散障一,第二固体电解质层上有气体室一、气体室二、气体室三、第一辅助电极、第二辅助电极、测量电极、扩散障二和扩散障三,第四固体电解质层侧面有参比气体通道和参比电极,该芯片使用方法为：气体通过开口一处扩散障一流入,将气体中氨气氧化为氮氧化物,转化为电势施加到测量电极上,通过检测第二辅助电极和测量电极之间泵电流,确定氨气浓度。本发明解决了普通氨气传感器芯片寿命短,不能在高温条件下使用的问题,灵敏度高,响应速度快,可靠性强。(The invention discloses an electrochemical ammonia gas sensor chip, which is integrally flaky and comprises a first solid electrolyte layer, a second solid electrolyte layer, a third solid electrolyte layer, a fourth solid electrolyte layer and a fifth solid electrolyte layer, wherein the first solid electrolyte layer is provided with a first opening and a first diffusion barrier, the second solid electrolyte layer is provided with a first gas chamber, a second gas chamber, a third gas chamber, a first auxiliary electrode, a second auxiliary electrode, a measuring electrode, a second diffusion barrier and a third diffusion barrier, and the side surface of the fourth solid electrolyte layer is provided with a reference gas channel and a reference electrode, and the using method of the chip is as follows: and the gas flows in through the diffusion barrier at the opening, ammonia in the gas is oxidized into nitrogen oxides, the nitrogen oxides are converted into electric potential and applied to the measuring electrode, and the concentration of the ammonia gas is determined by detecting the pump current between the second auxiliary electrode and the measuring electrode. The invention solves the problems that the common ammonia gas sensor chip has short service life and can not be used under the high-temperature condition, and has high sensitivity, high response speed and strong reliability.)

1. An electrochemical ammonia gas sensor chip is characterized in that the ammonia gas sensor chip is a sheet-shaped ammonia gas sensor chip integrally, the ammonia gas sensor chip sequentially comprises a first solid electrolyte layer, a second solid electrolyte layer, a third solid electrolyte layer, a fourth solid electrolyte layer and a fifth solid electrolyte layer from top to bottom, an opening first position is arranged on the first solid electrolyte layer, a diffusion barrier first is embedded in the opening first position, the second solid electrolyte layer is integrally positioned between the first solid electrolyte layer and the third solid electrolyte layer, a gas chamber first, a gas chamber second and a gas chamber third are arranged on the second solid electrolyte layer, a diffusion barrier second is arranged between the gas chamber first and the gas chamber second, a diffusion barrier third is arranged between the gas chamber second and the gas chamber third, a first auxiliary electrode is arranged on the upper top surface and the lower bottom surface in the gas chamber first, and a second auxiliary electrode is arranged on the upper top surface and the lower bottom surface in the gas chamber second, and measuring electrodes are arranged on the upper top surface and the lower bottom surface in the gas chamber III, the whole fourth solid electrolyte layer is positioned between the third solid electrolyte layer and the fifth solid electrolyte layer, a reference gas channel is arranged on the side surface of the fourth solid electrolyte layer, and a reference electrode is arranged on the upper top surface in the reference gas channel.

2. An electrochemical gas sensor chip according to claim 1, wherein the ammonia gas sensor chip comprises, in order from top to bottom, a first solid electrolyte layer, a second solid electrolyte layer, a third solid electrolyte layer, a fourth solid electrolyte layer, and a fifth solid electrolyte layer, wherein the first solid electrolyte layer, the second solid electrolyte layer, the third solid electrolyte layer, the fourth solid electrolyte layer, and the fifth solid electrolyte layer are all made of yttrium-containing stabilized zirconia nanopowder;

the first solid electrolyte layer, the second solid electrolyte layer, the third solid electrolyte layer, the fourth solid electrolyte layer and the fifth solid electrolyte layer are prepared by mixing Shenggobain 5Y-ZrO2 powder, PVB binder and solvent butanone, ball milling for 96 hours, defoaming and tape casting to prepare a first solid electrolyte layer, a second solid electrolyte layer, a third solid electrolyte layer, a fourth solid electrolyte layer and a fifth solid electrolyte layer of a green body, and after the first solid electrolyte layer, the second solid electrolyte layer, the third solid electrolyte layer and the fourth solid electrolyte layer which are subjected to screen printing are sequentially laminated and bonded from top to bottom through screen printing of corresponding first auxiliary electrodes, second auxiliary electrodes, measuring electrodes and reference electrodes on corresponding positions of the first solid electrolyte layer, the second solid electrolyte layer and the third solid electrolyte layer of the green body, the ceramic material is prepared by sequentially laminating, bonding and sintering from top to bottom, wherein the sintering temperature is 1520 +/-10 ℃.

3. The electrochemical gas sensor chip according to claim 1, wherein the first diffusion barrier, the second diffusion barrier and the third diffusion barrier are all composed of alumina powder and saint gobain 5Y-ZrO2 powder, and the first diffusion barrier, the second diffusion barrier and the third diffusion barrier are all microporous diffusion barriers.

4. An electrochemical gas sensor chip according to claim 1, characterized in that the first auxiliary electrode, the second auxiliary electrode and the measuring electrode are made of a catalytically active material rhodium or platinum rhodium alloy.

5. An electrochemical gas sensor chip according to claim 1, characterized in that said reference electrode is made of the catalytically active material platinum.

6. An electrochemical gas sensor chip according to any one of claims 1 to 5, wherein said diffusion barrier is integrally fitted in an opening portion of the upper surface of the first solid electrolyte layer, and the diffusion barrier is positioned above the first auxiliary electrode on an upper surface of the gas cell.

7. The electrochemical gas sensor chip according to claim 2 or 3, wherein the saint-goban 5Y-ZrO2 powder is produced by saint-goban France, the PVB binder is produced by Luoyangshun chemical products, Inc., the solvent butanone is produced by Jiangsu Jiasong chemical products, Inc., and the alumina powder is produced by Jiu Peng Xin New materials, Inc., Zhejiang.

8. The method for using the electrochemical gas sensor chip as claimed in claim 1, wherein the method for using the ammonia gas sensor chip comprises the following steps: a first auxiliary electrode and a second auxiliary electrode are respectively arranged on the left side of the measuring electrode in the gas chamber III and in the gas chamber I and the gas chamber II, the gas mixture flowing in through the diffusion barrier one at the opening one on the first solid electrolyte layer, the nitrogen oxides and the oxygen in the gas mixture are reduced and removed by a first auxiliary electrode in a first gas chamber, the ammonia gas in the gas mixture is oxidized into nitrogen oxide by the second auxiliary electrode in the gas chamber II, the nitrogen oxide generated by the oxidation of the second auxiliary electrode in the gas chamber II flows into the gas chamber III and is reduced by the measuring electrode in the gas chamber III, the nitrogen oxide formed by the oxidation of the ammonia gas in the process is converted into reduced potential to be applied to the measuring electrode in the gas chamber III, by detecting the pump current flowing between the second auxiliary electrode and the measuring electrode and using it for determining the concentration of ammonia present in the gas mixture.

9. The method for using the electrochemical gas sensor chip according to claim 8, wherein the ammonia gas sensor chip comprises a first solid electrolyte layer, a second solid electrolyte layer, a third solid electrolyte layer, a fourth solid electrolyte layer and a fifth solid electrolyte layer, the side surface of the fourth solid electrolyte layer is provided with a reference gas channel, the left side of the reference gas channel is provided with a gas inlet, the gas inlet of the reference gas channel can be contacted with air, the second solid electrolyte layer is internally provided with a gas chamber I, a gas chamber II and a gas chamber III, a diffusion barrier II is arranged between the gas chamber I and the gas chamber II, a diffusion barrier III is arranged between the gas chamber II and the gas chamber III, the first opening on the first solid electrolyte layer can be contacted with a gas mixture to be detected, the gas chamber I is provided with a first auxiliary electrode, and the gas chamber II is provided with a second auxiliary electrode, a reference electrode is arranged in the reference gas channel, the first auxiliary electrode and the reference electrode form a first pump cell, the second auxiliary electrode and the reference electrode form a second pump cell, the first pump cell can form oxygen constant pressure in a gas chamber I, the diffusion barrier I is arranged in the diffusion direction of the gas mixture, the diffusion barrier I is integrally positioned above the first auxiliary electrode, the first pump cell and the second pump cell can respectively operate in different limit current ranges, the measuring electrode in the gas chamber III is integrally positioned at the downstream of the first auxiliary electrode and the second auxiliary electrode, the measuring electrode and the reference electrode form a third pump cell, when a potential is applied to the first auxiliary electrode, the potential can reduce and remove oxygen and nitrogen oxides flowing into the gas mixture in the gas chamber I from the diffusion barrier, and the potential can not decompose ammonia in the gas mixture, ammonia enters the second gas chamber through the second diffusion barrier, and the potential applied to the first auxiliary electrode is in a range of-400 mV to-800 mV relative to the potential of the reference electrode;

the ammonia enters the gas chamber II through the diffusion barrier II, potential is applied to a second auxiliary electrode in the gas chamber II, the potential can quantitatively oxidize the ammonia in a gas mixture entering the gas chamber II into nitric oxide, the nitric oxide enters the gas chamber III through the diffusion barrier III to be detected, and the potential applied to the second auxiliary electrode is in a range of 100 mV-700 mV relative to the potential of a reference electrode;

the first diffusion barrier, the second diffusion barrier and the third diffusion barrier can limit the flow speed and the flow of different gases;

the nitric oxide enters the gas chamber III through the diffusion barrier III, a potential is applied to the measuring electrode in the gas chamber III, the potential can quantitatively reduce the nitric oxide in the gas mixture entering the gas chamber III, a pump current flowing to a third pump cell between the measuring electrode and a reference electrode is detected, the pump current is used for measuring the concentration of ammonia contained in the gas mixture flowing from the position of the opening on the first solid electrolyte layer, and the potential applied to the measuring electrode relative to the potential of the reference electrode is in a range of-100 mV to-500 mV.

Technical Field

The invention relates to the field of electrochemical ammonia gas sensor chips and use methods thereof, and particularly belongs to an electrochemical ammonia gas sensor chip and a use method thereof.

Background

The engines of motor vehicles being operated by burning fuel in the interior of the machineBurning and directly converting the heat energy released by the burning into power. At present, lean combustion mixture is preferably used as fuel for saving fuel, but harmful nitrogen oxide N0x as pollution gas is generated in the process, and the emission of N0x is reduced, so that the requirement of reaching the standard emission of engine exhaust gas is met. SCR systems that employ urea as a selective catalytic reductant are widely used in the aftertreatment of engine exhaust. The principle is that urea is injected into a tail gas pipe and is heated and decomposed into NH₃Reaction with N0x to harmless N₂And H₂0. For precise control of NH₃Content, NH needs to be installed in the exhaust pipe₃The sensor monitors the concentration of NH3 on line and feeds back an electric signal to the control system.

With the continuous change of the domestic requirement on the standard emission of the environmental gas, the research on the ammonia NH3 sensor is gradually increased. Such as: the patent document with application number 202010321909.2 describes that the sensitive material is Mg (1-x) CuxO (0< x <0.67), which can selectively adsorb NH3 to a three-phase interface to generate electrochemical catalytic oxidation, and thus the sensor using the sensitive material has extremely high sensitivity to NH 3. The ammonia gas sensor manufactured by the patent has the defect of short service life;

the patent document with the application number of 201921310062.7 discloses an electrochemistry ammonia sensor, which comprises a shell, a cover is arranged on an opening of the shell, a gas diffusion air inlet hole is formed in the cover, a polytetrafluoroethylene supporting pore plate is arranged in the shell, a built-in cavity is arranged between the polytetrafluoroethylene supporting pore plate and the bottom of the shell, electrolyte is filled in the built-in cavity, a working electrode, a reference electrode and a counter electrode are sequentially stacked and arranged in the shell from the cover to the direction of the polytetrafluoroethylene supporting pore plate, the working electrode, the reference electrode and the counter electrode are porous electrodes, a first separation layer is arranged between the working electrode and the reference electrode, a second separation layer is arranged between the reference electrode and the counter electrode, and electrode pins connected with the working electrode, the reference electrode and the counter electrode. The electrochemical ammonia gas sensor greatly improves the sensitivity and response speed to ammonia gas. However, the embodiment of the electrochemical ammonia gas sensor manufactured by the patent can only be used under normal temperature conditions, is not suitable and cannot be used under high temperature conditions.

Therefore, in order to meet the requirement of an ammonia gas sensor chip which is used in high-temperature automobile tail gas for a long time and has strong reliability and high sensitivity on the market, the invention provides an electrochemical ammonia gas sensor chip and a using method thereof. The method is suitable for popularization and use in the production and manufacture of ammonia sensors in automobile engines and supporting industries.

Disclosure of Invention

The invention provides an electrochemical ammonia gas sensor chip, which solves the problems mentioned in the background technology through the overall research and development design of a first solid electrolyte layer, a second solid electrolyte layer, a third solid electrolyte layer, a fourth solid electrolyte layer and a fifth solid electrolyte layer, wherein the first solid electrolyte layer is provided with a first opening and a first diffusion barrier, the second solid electrolyte layer is provided with a first gas chamber, a second gas chamber, a third gas chamber, a first auxiliary electrode, a second auxiliary electrode, a measuring electrode, a second diffusion barrier and a third diffusion barrier, and a reference gas channel and a reference electrode on the side surface of the fourth solid electrolyte layer. Meanwhile, the sensor chip can measure the concentration of ammonia contained in a gas mixture, can be used as a sensor chip for measuring the concentration of ammonia in high-temperature tail gas of an automobile for a long time, solves the problems that the common ammonia sensor chip is short in service life and cannot be used under a high-temperature condition, and is high in sensitivity, high in response speed, good in using effect and strong in reliability. The method is suitable for popularization and use in the production and manufacture of ammonia sensors in automobile engines and supporting industries.

The technical scheme adopted by the invention for realizing the aim is as follows:

an electrochemical ammonia gas sensor chip is characterized in that the ammonia gas sensor chip is a sheet-shaped ammonia gas sensor chip integrally, the ammonia gas sensor chip sequentially comprises a first solid electrolyte layer, a second solid electrolyte layer, a third solid electrolyte layer, a fourth solid electrolyte layer and a fifth solid electrolyte layer from top to bottom, an opening first position is arranged on the first solid electrolyte layer, a diffusion barrier first is embedded in the opening first position, the second solid electrolyte layer is integrally positioned between the first solid electrolyte layer and the third solid electrolyte layer, a gas chamber first, a gas chamber second and a gas chamber third are arranged on the second solid electrolyte layer, a diffusion barrier second is arranged between the gas chamber first and the gas chamber second, a diffusion barrier third is arranged between the gas chamber second and the gas chamber third, a first auxiliary electrode is arranged on the upper top surface and the lower bottom surface in the gas chamber first, and a second auxiliary electrode is arranged on the upper top surface and the lower bottom surface in the gas chamber second, and measuring electrodes are arranged on the upper top surface and the lower bottom surface in the gas chamber III, the whole fourth solid electrolyte layer is positioned between the third solid electrolyte layer and the fifth solid electrolyte layer, a reference gas channel is arranged on the side surface of the fourth solid electrolyte layer, and a reference electrode is arranged on the upper top surface in the reference gas channel.

Further, the ammonia gas sensor chip comprises a first solid electrolyte layer, a second solid electrolyte layer, a third solid electrolyte layer, a fourth solid electrolyte layer and a fifth solid electrolyte layer from top to bottom in sequence, wherein the first solid electrolyte layer, the second solid electrolyte layer, the third solid electrolyte layer, the fourth solid electrolyte layer and the fifth solid electrolyte layer are all made of yttrium-containing stable zirconia nano-powder;

the first solid electrolyte layer, the second solid electrolyte layer, the third solid electrolyte layer, the fourth solid electrolyte layer and the fifth solid electrolyte layer are prepared by mixing Shenggobain 5Y-ZrO2 powder, PVB binder and solvent butanone, ball milling for 96 hours, defoaming and tape casting to prepare a first solid electrolyte layer, a second solid electrolyte layer, a third solid electrolyte layer, a fourth solid electrolyte layer and a fifth solid electrolyte layer of a green body, and after the first solid electrolyte layer, the second solid electrolyte layer, the third solid electrolyte layer and the fourth solid electrolyte layer which are subjected to screen printing are sequentially laminated and bonded from top to bottom through screen printing of corresponding first auxiliary electrodes, second auxiliary electrodes, measuring electrodes and reference electrodes on corresponding positions of the first solid electrolyte layer, the second solid electrolyte layer and the third solid electrolyte layer of the green body, sintering, wherein the sintering temperature is 1520 +/-10 ℃.

Further, the first diffusion barrier, the second diffusion barrier and the third diffusion barrier are all composed of alumina powder and saint gobain 5Y-ZrO2 powder, and the first diffusion barrier, the second diffusion barrier and the third diffusion barrier are microporous diffusion barriers.

Further, the first auxiliary electrode, the second auxiliary electrode and the measuring electrode are all made of a catalytically active material rhodium or a platinum rhodium alloy.

Further, the reference electrode is made of a catalytically active material platinum.

Furthermore, the diffusion barrier is integrally embedded in the opening on the first solid electrolyte layer, and the diffusion barrier is positioned on the first auxiliary electrode on the upper top surface of the gas chamber.

Further, the saint-goban 5Y-ZrO2 powder is produced by saint-goban france, the PVB binder is produced by luoyang rich chemical products ltd, the solvent butanone is produced by jia pine chemical ltd, and the alumina powder is produced by jiu peng new materials ltd.

The use method for measuring the ammonia concentration by adopting the electrochemical ammonia sensor chip comprises the following steps: a first auxiliary electrode and a second auxiliary electrode are respectively arranged on the left side of the measuring electrode in the gas chamber III and in the gas chamber I and the gas chamber II, the gas mixture flowing in through the diffusion barrier one at the opening one on the first solid electrolyte layer, the nitrogen oxides and the oxygen in the gas mixture are reduced and removed by a first auxiliary electrode in a first gas chamber, the ammonia gas in the gas mixture is oxidized into nitrogen oxide by the second auxiliary electrode in the gas chamber II, the nitrogen oxide generated by the oxidation of the second auxiliary electrode in the gas chamber II flows into the gas chamber III and is reduced by the measuring electrode in the gas chamber III, the nitrogen oxide formed by the oxidation of the ammonia gas in the process is converted into reduced potential to be applied to the measuring electrode in the gas chamber III, by detecting the pump current flowing between the second auxiliary electrode and the measuring electrode and using it for determining the concentration of ammonia present in the gas mixture.

Further, the ammonia gas sensor chip comprises a first solid electrolyte layer, a second solid electrolyte layer, a third solid electrolyte layer, a fourth solid electrolyte layer and a fifth solid electrolyte layer, wherein a reference gas channel is arranged on the side surface of the fourth solid electrolyte layer, a gas inlet is arranged on the left side of the reference gas channel, the gas inlet of the reference gas channel can be in contact with air, a first gas chamber, a second gas chamber and a third gas chamber are arranged in the second solid electrolyte layer, a second diffusion barrier is arranged between the first gas chamber and the second gas chamber, a third diffusion barrier is arranged between the second gas chamber and the third gas chamber, a first opening on the first solid electrolyte layer can be in contact with a gas mixture to be detected, a first auxiliary electrode is arranged in the first gas chamber, a second auxiliary electrode is arranged in the second gas chamber, a reference electrode is arranged in the reference gas channel, and the first auxiliary electrode and the reference electrode form a first pump cell, the second auxiliary electrode and the reference electrode form a second pump cell, the first pump cell is capable of creating a constant pressure of oxygen within the gas chamber one, the diffusion barrier I is in the diffusion direction of the gas mixture, the diffusion barrier I is entirely located above the first auxiliary electrode, the first pump cell and the second pump cell can be operated in different limiting current ranges, the measuring electrode in gas chamber three is located entirely downstream of the first auxiliary electrode and the second auxiliary electrode, the measuring electrode and the reference electrode forming a third pump cell, the potential is capable of reducing oxygen and nitrogen oxides from a gas mixture flowing from the diffusion barrier into the gas chamber, the potential is such that ammonia gas in the gas mixture cannot be decomposed, the ammonia gas entering the second gas chamber through the second diffusion barrier, the potential relative to the reference electrode, the potential applied to the first auxiliary electrode is in the range of-400 mV to-800 mV;

the ammonia enters the gas chamber II through the diffusion barrier II, potential is applied to a second auxiliary electrode in the gas chamber II, the potential can quantitatively oxidize the ammonia in a gas mixture entering the gas chamber II into nitric oxide, the nitric oxide enters the gas chamber III through the diffusion barrier III to be detected, and the potential applied to the second auxiliary electrode is in a range of 100 mV-700 mV relative to the potential of a reference electrode;

the first diffusion barrier, the second diffusion barrier and the third diffusion barrier can limit the flow speed and the flow of different gases;

the nitric oxide enters the gas chamber III through the diffusion barrier III, a potential is applied to the measuring electrode in the gas chamber III, the potential can quantitatively reduce the nitric oxide in the gas mixture entering the gas chamber III, a pump current flowing to a third pump cell between the measuring electrode and a reference electrode is detected, the pump current is used for measuring the concentration of ammonia contained in the gas mixture flowing from the position of the opening on the first solid electrolyte layer, and the potential applied to the measuring electrode relative to the potential of the reference electrode is in a range of-100 mV to-500 mV.

Compared with the prior art, the invention has the following beneficial effects:

an electrochemical ammonia gas sensor chip is manufactured by the whole development and design combination of the whole of the sheet-shaped ammonia gas sensor chip and a first solid electrolyte layer, a second solid electrolyte layer, a third solid electrolyte layer, a fourth solid electrolyte layer and a fifth solid electrolyte layer, wherein the first solid electrolyte layer is provided with a first opening and a first diffusion barrier, the second solid electrolyte layer is provided with a first gas chamber, a second gas chamber, a third gas chamber, a first auxiliary electrode, a second auxiliary electrode, a measuring electrode, a second diffusion barrier and a third diffusion barrier, and a reference gas channel and a reference electrode are arranged on the side surface of the fourth solid electrolyte layer, the electrochemical ammonia gas sensor chip is used for measuring the ammonia gas concentration by reducing and removing nitrogen oxides and oxygen in the gas mixture through the first diffusion barrier arranged at the first opening of the first solid electrolyte layer by the first auxiliary electrode in the first gas chamber, the ammonia gas in the gas mixture is oxidized to nitrogen oxides by the second auxiliary electrode in the second gas chamber, the nitrogen oxides produced by the oxidation of the ammonia gas by the second auxiliary electrode in the second gas chamber flow into the third gas chamber and are reduced by the measuring electrode in the third gas chamber, the nitrogen oxides formed by the oxidation of the ammonia gas in the process are converted into reduced potentials which are applied to the measuring electrode located in the third gas chamber, and the reduced potentials are used for determining the concentration of the ammonia gas present in the gas mixture by detecting the pump current flowing between the second auxiliary electrode and the measuring electrode.

The invention can measure the concentration of ammonia contained in the gas mixture, can be used as a sensor chip for measuring the concentration of ammonia in high-temperature tail gas of an automobile for a long time, solves the problems that the common ammonia sensor chip has short service life and can not be used under the high-temperature condition, and has high sensitivity, high response speed, good use effect and strong reliability.

Drawings

FIG. 1 is a schematic view of the overall structure of the present invention;

FIG. 2 is a longitudinal sectional view of the entire first solid electrolyte layer of the present invention taken perpendicular to the horizontal plane of the first internal diffusion barrier at the opening.

Remarks explanation: 1 is a first solid electrolyte layer; 11 is a first opening; 2 is a second solid electrolyte layer; 3 is a third solid electrolyte layer; 4 is a fourth solid electrolyte layer; 5 is a fifth solid electrolyte layer; c is a gas chamber I; c2 is gas chamber II; c3 is gas chamber III; c4 is a reference gas channel; r is a first diffusion barrier; r2 is a second diffusion barrier; r3 is diffusion barrier III; d is a first auxiliary electrode; d2 is a second auxiliary electrode; d3 is a measuring electrode; d4 is a reference electrode.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The present invention will be described in further detail with reference to examples and specific embodiments.

Referring to the drawings: an electrochemical ammonia gas sensor chip is characterized in that the ammonia gas sensor chip is a sheet-shaped ammonia gas sensor chip integrally, the ammonia gas sensor chip sequentially comprises a first solid electrolyte layer 1, a second solid electrolyte layer 2, a third solid electrolyte layer 3, a fourth solid electrolyte layer 4 and a fifth solid electrolyte layer 5 from top to bottom, an opening position 11 is arranged on the first solid electrolyte layer 1, a diffusion barrier R is embedded in the opening position 11, the second solid electrolyte layer 2 is integrally positioned between the first solid electrolyte layer 1 and the third solid electrolyte layer 3, a gas chamber C, a gas chamber II C2 and a gas chamber III C3 are arranged on the second solid electrolyte layer 2, a diffusion barrier II R2 is arranged between the gas chamber I C and the gas chamber II C2, a diffusion barrier III R3 is arranged between the gas chamber II C2 and the gas chamber III C3, a first auxiliary electrode D is arranged on the top surface and the bottom surface in the gas chamber I C, the second auxiliary electrode D2 is provided at both the upper top surface and the lower bottom surface in the second gas chamber C2, the measuring electrode D3 is provided at both the upper top surface and the lower bottom surface in the third gas chamber C3, the whole of the fourth solid electrolyte layer 4 is located between the third solid electrolyte layer 3 and the fifth solid electrolyte layer 5, the reference gas channel C4 is provided on the side surface of the fourth solid electrolyte layer 4, and the reference electrode D4 is provided at the upper top surface in the reference gas channel C4.

Further, the ammonia gas sensor chip comprises a first solid electrolyte layer 1, a second solid electrolyte layer 2, a third solid electrolyte layer 3, a fourth solid electrolyte layer 4 and a fifth solid electrolyte layer 5 from top to bottom in sequence, wherein the first solid electrolyte layer 1, the second solid electrolyte layer 2, the third solid electrolyte layer 3, the fourth solid electrolyte layer 4 and the fifth solid electrolyte layer 5 are all made of yttrium-containing stable zirconia nano powder;

the first solid electrolyte layer 1, the second solid electrolyte layer 2, the third solid electrolyte layer 3, the fourth solid electrolyte layer 4 and the fifth solid electrolyte layer 5 are all prepared by mixing Shenggobain 5Y-ZrO2 powder, PVB binder and solvent butanone, ball milling is carried out for 96 hours, then defoaming and tape casting are carried out to prepare a green first solid electrolyte layer 1, a green second solid electrolyte layer 2, a green third solid electrolyte layer 3, a green fourth solid electrolyte layer 4 and a green fifth solid electrolyte layer 5, corresponding positions of the green first solid electrolyte layer 1, the green second solid electrolyte layer 2 and the green third solid electrolyte layer 3 are respectively screen-printed with a corresponding first auxiliary electrode D, a corresponding second auxiliary electrode D2, a corresponding measuring electrode D3 and a corresponding reference electrode D4, and the screen-printed first solid electrolyte layer 1, the green second solid electrolyte layer 2 and the green third solid electrolyte layer 3 are respectively, and the fourth solid electrolyte layer 4 and the fifth solid electrolyte layer 5 are laminated, bonded and sintered from top to bottom, wherein the sintering temperature is 1520 +/-10 ℃.

Further, the first diffusion barrier R, the second diffusion barrier R2 and the third diffusion barrier R3 are all composed of alumina powder and saint gobain 5Y-ZrO2 powder, and the first diffusion barrier R, the second diffusion barrier R2 and the third diffusion barrier R3 are microporous diffusion barriers.

Further, the first auxiliary electrode D, the second auxiliary electrode D2 and the measuring electrode D3 are all made of a catalytically active material rhodium or a platinum-rhodium alloy.

Further, the reference electrode D4 was made of the catalytically active material platinum.

Further, the diffusion barrier one R is integrally fitted inside the opening one place 11 on the first solid electrolyte layer 1, the diffusion barrier one R being located on the top surface of the gas chamber one C above the first auxiliary electrode D.

Further, the saint-goban 5Y-ZrO2 powder is produced by saint-goban france, the PVB binder is produced by luoyang rich chemical products ltd, the solvent butanone is produced by jia pine chemical ltd, and the alumina powder is produced by jiu peng new materials ltd.

The use method for measuring the ammonia concentration by adopting the electrochemical ammonia sensor chip comprises the following steps: on the left side of the measuring electrode D3 in the gas chamber three C3, the first auxiliary electrode D and the second auxiliary electrode D2 are respectively arranged in the gas chamber one C and the gas chamber two C2, the diffusion barrier one R at one opening 11 on the first solid electrolyte layer 1 is passed through, the inflowing gas mixture, the nitrogen oxide and the oxygen in the gas mixture are reduced and removed by the first auxiliary electrode D in the gas chamber one C, the ammonia gas in the gas mixture is oxidized into the nitrogen oxide by the second auxiliary electrode D2 in the gas chamber two C2, the nitrogen oxide oxidized by the second auxiliary electrode D2 in the gas chamber two C2 flows into the gas chamber three C3 and is reduced by the measuring electrode D3 in the gas chamber three C3, the nitrogen oxide oxidized by the ammonia gas in the process is converted into the reduced potential and is applied to the measuring electrode D3 in the gas chamber three C3, and the pumping current flowing between the second auxiliary electrode D2 and the measuring electrode D3 is detected, and is used to determine the concentration of ammonia gas present in the gas mixture.

Further, the ammonia gas sensor chip comprises a first solid electrolyte layer 1, a second solid electrolyte layer 2, a third solid electrolyte layer 3, a fourth solid electrolyte layer 4 and a fifth solid electrolyte layer 5, wherein a reference gas channel C4 is arranged on the side surface of the fourth solid electrolyte layer 4, a gas inlet is arranged on the left side of the reference gas channel C4, the gas inlet of the reference gas channel C4 can be contacted with air, a gas chamber I C, a gas chamber II C2 and a gas chamber III C3 are arranged in the second solid electrolyte layer 2, a diffusion barrier II R2 is arranged between the gas chamber I C and the gas chamber II C2, a diffusion barrier III R3 is arranged between the gas chamber II C2 and the gas chamber III C3, a position 11 on the upper surface of the first solid electrolyte layer 1 can be contacted with a gas mixture to be detected, a first auxiliary electrode D is arranged in the gas chamber I C, a second auxiliary electrode D2 is arranged in the gas chamber II C2, reference gas channel C4 has reference electrode D4, which first auxiliary electrode D forms with reference electrode D4 a first pump cell, which second auxiliary electrode D2 forms with reference electrode D4 a second pump cell, which first pump cell is capable of forming an oxygen constant pressure in gas chamber C, which diffusion barrier R is in the direction of diffusion of the gas mixture, which diffusion barrier R is situated overall above first auxiliary electrode D, which first pump cell and second pump cell are capable of operating in different limiting current ranges, respectively, which measuring electrode D3 in gas chamber C3 is situated overall downstream of first auxiliary electrode D2, which measuring electrode D3 forms with reference electrode D4 a third pump cell, which potential, when a potential is applied to first auxiliary electrode D, is capable of removing oxygen and reducing nitrogen oxides from the gas mixture flowing from diffusion barrier R into gas chamber C, this potential does not decompose the ammonia in the gas mixture, which enters the gas chamber di C2 through the diffusion barrier di R2, said potential applied to the first auxiliary electrode D being in the range-400 mV to-800 mV relative to the potential of the reference electrode D4;

the ammonia enters a gas chamber II C2 through a diffusion barrier II R2, a potential is applied to a second auxiliary electrode D2 in a gas chamber II C2, the potential can enable the ammonia entering a gas mixture in the gas chamber II C2 to be quantitatively oxidized into nitric oxide, the nitric oxide enters a gas chamber III C3 through a diffusion barrier III R3 to be tested, and the potential applied to the second auxiliary electrode D2 relative to the potential of a reference electrode D4 ranges from 100mV to 700 mV;

the first diffusion barrier R, the second diffusion barrier R2 and the third diffusion barrier R3 can limit the flow speed and the flow of different gases;

said nitric oxide enters the gas chamber tri C3 through the diffusion barrier tri R3, a potential is applied across the measuring electrode D3 in the gas chamber tri C3, which potential is capable of quantitatively reducing the nitric oxide in the gas mixture entering the gas chamber tri C3, while a pump current is detected which flows to the third pump cell between the measuring electrode D3 and the reference electrode D4, the ammonia concentration contained in the gas mixture flowing in from the opening 11 in the first solid electrolyte layer 1 being measured as said pump current, said potential applied across the measuring electrode D3 being in the range from-100 mV to-500 mV relative to the potential of the reference electrode D4.

The invention integrally develops and designs the combination of the whole of the sheet-shaped ammonia gas sensor chip and the first solid electrolyte layer 1, the second solid electrolyte layer 2, the third solid electrolyte layer 3, the fourth solid electrolyte layer 4 and the fifth solid electrolyte layer 5, wherein the first solid electrolyte layer 1 is provided with the opening 11 and the diffusion barrier R, the second solid electrolyte layer 2 is provided with the gas chamber C, the gas chamber C2, the gas chamber C3, the first auxiliary electrode D, the second auxiliary electrode D2, the measuring electrode D3, the diffusion barrier R2 and the diffusion barrier R3, and the whole of the reference gas channel C4 and the reference electrode D4 on the side surface of the fourth solid electrolyte layer 4, so as to manufacture the electrochemical ammonia gas sensor chip, the using method of the electrochemical ammonia gas sensor chip for measuring the ammonia gas concentration is that the diffusion barrier R at the opening 11 on the first solid electrolyte layer 1, the nitrogen oxides and oxygen in the gas mixture flowing in are reduced and removed by the first auxiliary electrode D in the gas chamber I C, the ammonia gas in the gas mixture is oxidized into nitrogen oxides by the second auxiliary electrode D2 in the gas chamber II C2, the nitrogen oxides generated by the oxidation of the second auxiliary electrode D2 in the gas chamber II C2 flow into the gas chamber III C3 and are reduced by the measuring electrode D3 in the gas chamber III C3, the nitrogen oxides formed by the oxidation of the ammonia gas in the process are converted into reduced potential and are applied to the measuring electrode D3 in the gas chamber III C3, and the concentration of the ammonia gas existing in the gas mixture is determined by detecting the pump current flowing between the second auxiliary electrode D2 and the measuring electrode D3.

The invention can measure the concentration of ammonia contained in the gas mixture, can be used as a sensor chip for measuring the concentration of ammonia in high-temperature tail gas of an automobile for a long time, solves the problems that the common ammonia sensor chip has short service life and can not be used under the high-temperature condition, and has high sensitivity, high response speed, good use effect and strong reliability. The method is suitable for popularization and use in the production and manufacture of ammonia sensors in automobile engines and supporting industries.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various changes and modifications can be made without departing from the inventive concept of the present invention, and these changes and modifications are all within the scope of the present invention.