A micro handheld nanoparticle detection device and detection method

Abstract

The present invention relates to a miniature handheld nano-scale particle detection device and detection method. The device includes an aerosol photocharger, an aerosol precipitator, and an aerosol hybrid condensation particle counter; the aerosol photocharger includes a charging shell, a UVC light-emitting device, and a metal electron collection net; the aerosol precipitator includes a precipitator body and an electrically insulating gasket; the precipitator body includes a first metal plate, a metal disk, and a second metal plate; a first gap is left between the first metal plate and the metal disk, and the gap forms a first flow chamber with the inner wall of the electrically insulating gasket; a second gap is left between the second metal plate and the metal disk, and the gap forms a second flow chamber with the inner wall of the electrically insulating gasket; the aerosol hybrid condensation particle counter includes an aerosol growth module and a photoelectric detection module. The present invention has the characteristics of a simple measurement device structure and a small size, and can achieve direct measurement of the particle size spectrum of low-concentration ultrafine particles and large-scale point measurement.

Description

Technical Field

[0001] The present invention relates to the technical field of ultrafine particle exposure detection, and in particular to a miniature handheld nano-scale particle detection device and a detection method. Background Art

[0002] Nanoparticles in the atmosphere are a major contributor to air pollution problems such as smog. The State Key Laboratory of Environmental Chemistry and Ecotoxicology at the Eco-Environmental Research Center has found exogenous ultrafine particles in the blood and pleural effusions of the general population. Ultrafine particles, when inhaled through the nose, can deposit in tissues and organs such as the lungs, nose, pharynx, larynx, bronchi, trachea, alveoli, and brain. Despite numerous epidemiological and toxicological studies linking exposure to nanoparticles to adverse health effects, particle count and size distribution concentration, two key indicators of toxic aerosols, remain unregulated.

[0003] Submicron and nanometer particles are present in the exhaust gases of various combustion sources, chemical processes, and aerosol reactors. Examples include diesel and jet engine exhaust, coal-fired power plant emissions, and welding fumes. These nanoparticles are considered environmental pollutants. Furthermore, with the development of the nanotechnology and semiconductor industries, nanoparticles of various materials are synthesized in chemical reactors for use in a variety of modern industrial applications. Furthermore, nanoparticles can affect semiconductor process performance, making it particularly important to monitor the particle size distribution of nanoparticles in semiconductor production plants.

[0004] At present, commercial aerosol detection instruments mainly include laser scattering intensity detection method based on the principle of light scattering, aerodynamic particle size detection method based on kinematic properties, and electric mobility detection method based on particle electric mobility. Aerodynamic and light scattering methods are mostly suitable for measuring micron-sized particles, while instruments based on the electric mobility principle are suitable for measuring nanometer and submicron-sized particles. However, the current instruments based on the electric mobility principle are large in size and high in cost, making them unsuitable for portable measurements and large-scale point measurements. At the same time, the charging modules of instruments based on the electric mobility principle mostly use diffusion charging, corona charging, etc. This type of method easily produces ozone during the discharge process, and the tungsten needle needs to be replaced regularly; the particle collection module mostly uses a Faraday cup electrometer, which is not suitable for measurements in low-concentration environments.

[0005] Therefore, it is necessary to develop a low-detection-limit, low-cost, miniaturized nanoscale portable ultrafine particle size spectrometer. Summary of the Invention

[0006] The purpose of the present invention is to provide a miniature handheld nano-scale particle detection device and detection method, which can solve the shortcomings of the existing technology, have the characteristics of simple measurement equipment structure, small size, low detection limit, etc., and can realize direct measurement of ultrafine particle size spectrum and large-scale point measurement.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] In a first aspect of the present invention, a miniature handheld nano-scale particle detection device is disclosed.

[0009] A miniature handheld nano-scale particle detection device comprises an aerosol photocharger, an aerosol precipitator and an aerosol hybrid condensation particle counter which are arranged in sequence;

[0010] The aerosol photocharger comprises a charged shell and a UVC light emitting device and a metal electron collecting net mounted on the charged shell;

[0011] The aerosol precipitator includes a precipitator body and an electrically insulating gasket sleeved outside the precipitator body; the precipitator body includes a first metal plate, a metal disc, and a second metal plate arranged in sequence; the metal disc is provided with a plurality of through holes; a first gap is left between the first metal plate and the metal disc, and the gap and the inner wall of the electrically insulating gasket form a first flow chamber; a second gap is left between the second metal plate and the metal disc, and the gap and the inner wall of the electrically insulating gasket form a second flow chamber; the through holes are used to connect the first flow chamber with the second flow chamber;

[0012] The aerosol hybrid condensation particle counter comprises a particle growth module and a photoelectric detection module which are arranged in sequence.

[0013] Furthermore, the charging housing has a charging aerosol inlet and a charging aerosol outlet coaxially arranged;

[0014] The charged housing is provided with sealing rubber rings on both sides of the UVC light emitting device;

[0015] The lower end of the charged shell is in a 45° slope.

[0016] Furthermore, the light emitted by the UVC light emitting device is perpendicular to the flow direction of the aerosol.

[0017] Furthermore, the metal electron collecting net is fixed inside the charged shell, and is located on both sides of the aerosol airflow with the UVC light emitting device.

[0018] Furthermore, an inlet pipe is provided on the first metal plate, and the inlet pipe is connected to the interior of the charged housing;

[0019] An outlet pipe is provided on the second metal plate, and the outlet pipe is connected to the aerosol mixed condensation particle counter.

[0020] Furthermore, the metal disk is connected to high voltage electricity, and the first metal plate and the second metal plate are grounded or biased to a separate potential relative to the metal disk, thereby establishing an electric field in the first flow chamber and the second flow chamber respectively, forming a separate electric field that is not grounded with other electronic equipment of the instrument.

[0021] Furthermore, the particle growth module includes an aerosol growth chamber shell and a liquid storage tank connected to the aerosol growth chamber shell; a heating kit, a cooling kit and an insulation kit are provided on the outer wall of the aerosol growth chamber shell; a first aerosol air inlet, an aerosol air outlet and a working liquid inlet are provided on the aerosol growth chamber shell; the first aerosol air inlet is connected to the outlet of the aerosol precipitator; the working liquid inlet is connected to the liquid storage tank; the heating kit is used to heat the working liquid to turn it into steam; the cooling kit is used to reduce the temperature of the aerosol; the insulation kit is used to insulate and allow hot steam and cold aerosol to be thermally mixed; the liquid storage tank is used to store the working liquid;

[0022] The photoelectric detection module includes a photoelectric detection cavity and a photoelectric emitter and a photoelectric detector installed on the photoelectric detection cavity; a second aerosol outlet is opened on the photoelectric detection cavity.

[0023] Furthermore, the device also includes a main control module;

[0024] The main control module includes a controller, a vacuum pump, a scanning voltage module, a power supply module and a photoelectric signal processing module;

[0025] The output end of the controller is connected to the input end of the scanning voltage module and the input end of the vacuum pump respectively;

[0026] The output end of the scanning voltage module is connected to the first metal plate, the second metal plate and the metal disk respectively;

[0027] The photoelectric signal processing module is connected to the photoelectric detector;

[0028] The vacuum pump is connected to the first aerosol outlet and the second aerosol outlet respectively.

[0029] In a second aspect of the present invention, a detection method of the above detection device is disclosed.

[0030] The method includes:

[0031] (1) Aerosol sample gas enters the aerosol photocharger at a certain flow rate.

[0032] (2) The UVC light emitting device in the aerosol photocharger emits UVC light. The UVC light collides with the aerosol, causing the aerosol to lose electrons. The escaped electrons are collected by the metal electron collection net, causing the ultrafine particles in the aerosol sample to be positively charged, thus obtaining charged particles.

[0033] (3) Charged particles are introduced into the first flow chamber of the aerosol precipitator, and the charged particles move radially outward, pass through the through holes on the metal plate, enter the second flow chamber and radially converge to the outlet pipe; when a fixed electric field is established on the first flow chamber or the second flow chamber, the trajectory of the charged particles is deflected, and the charged particles that meet the set electrical mobility are deposited on the first metal plate or the second metal plate, and the remaining charged particles will partially or completely leave the aerosol precipitator and enter the aerosol hybrid condensation particle counter.

[0034] (4) The ultrafine particles entering the aerosol mixing condensation particle counter are mixed with the working fluid vapor that has been cooled by the refrigeration kit and heated by the heating kit, thereby achieving condensation growth of the ultrafine particles; the ultrafine particles after condensation and growth pass through the photoelectric detection cavity and eventually leave through the aerosol outlet. The working fluid is stored in a liquid storage tank. The working fluid is heated by the heating kit to form working fluid vapor. The ultrafine particles (aerosol) and the working fluid vapor are mixed at the T-shaped joint of the aerosol growth chamber shell. When the hot working fluid vapor mixes with the cold particles, they begin to grow. The hot vapor will wrap around the particles, thereby increasing the volume of the particles to a size that can be detected by the photoelectric detection module.

[0035] (5) When the condensed and grown ultrafine particles pass through the photoelectric detection cavity, the photoelectric detector will generate pulses. After the pulses are processed by the photoelectric signal processing module, the number of ultrafine particles of the corresponding particle size under the corresponding scanning voltage is obtained, and the concentration of ultrafine particles under the particle size is determined.

[0036] Furthermore, the method also includes: when the flow rate of the sample gas is stable, changing the scanning voltage between the metal disk and the first metal plate and the second metal plate, graded detecting the concentration of ultrafine particles at different particle sizes, and drawing a particle size spectrum according to the concentration of ultrafine particles at different particle sizes.

[0037] Compared with the prior art, the advantages of the present invention are:

[0038] (1) The micro-aerosol photocharger in the present invention uses UVC light source irradiation to charge the aerosol. Compared with traditional corona discharge, UVC light source irradiation is more efficient for charging aerosols below 20nm, operates stably, and is less likely to produce ozone. Compared with UV (~5eV) irradiation, the diffusion charging rate under soft X-ray irradiation is improved. However, the high cost and limited lifespan of soft X-ray light sources make them difficult to use.

[0039] (2) The present invention removes the sheath gas structure of the particle size detection module, which reduces the loss of particles compared to the traditional electromigration detection method and greatly improves the lower limit of ultrafine particle detection concentration. The detection device described in the present invention has a simple structure and a small size, and can realize the classification detection of ultrafine particles in the small particle size range of 10nm to 200nm. Although removing the sheath gas circulation will reduce the number of particle size classification channels, the impact is very small because it is unnecessary to have too many particle size classification channels when the concentration is low. However, removing the sheath gas circulation will greatly reduce the loss of the measured particles, thereby improving the detection sensitivity of ultrafine particles in low concentration environments.

[0040] (3) The present invention adopts a flat-plate electromigration detection method, which has a simpler structure, a lighter volume, and a higher detection effect and accuracy of the detection results than the traditional cylindrical electromigration detection method.

[0041] (4) The present invention uses a hybrid condensation particle growth method. Compared to the traditional heat conduction condensation particle growth method, this method mixes cold particles with an excess of hot, wet working fluid vapor. By making the mixing zone highly turbulent, it promotes rapid, nearly adiabatic mixing, enabling aerosols to grow rapidly in a small space with minimal diffusion losses. Turbulent mixing can quickly achieve uniform composition with minimal particle diffusion losses. Using this method, particle growth of 10 microns can be achieved in less than 100 milliseconds.

[0042] (5) The nanoparticle detection device of the present invention has the advantages of low cost and small size, and is suitable for monitoring in various locations. The present invention uses an ultrafine particle detection particle size spectrometer that integrates a photocharger, an aerosol precipitator, and an aerosol hybrid condensation particle counter. Due to the use of optical detection methods, it can measure the particle size distribution of ultrafine particles in low concentration environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a structural schematic diagram of the detection device in the present invention;

[0044] Figure 2 is a top view of the metal disk of the present invention;

[0045] Figure 3 It is a flow chart of the detection method of the present invention.

[0046] in:

[0047] 1. Aerosol photocharger, 111. Charger aerosol inlet, 112. Charger aerosol outlet, 12. Charger cover, 13. Charger housing, 14. UVC light emitting device fixing frame, 15. UV light emitting device, 16. Metal electron collection net, 2. Micro-disc aerosol precipitator, 21. First metal plate, 221. Inlet pipe, 222. Outlet pipe, 23. Electrically insulating gasket, 24. First flow chamber, 25. Porous metal disc, 26. First Second flow chamber, 27. Second metal plate, 3. Aerosol mixing condensation particle counter, 311. Aerosol growth chamber shell, 312. Photoelectric detection chamber, 32. Refrigeration kit, 33. Photoelectric detector, 34. Photoelectric emitter, 35. Heating kit, 36. Liquid storage tank, 37. Insulation kit, 38. Particle growth module, 39. Photoelectric detection module, 4. Main control module, 41. Controller, 42. Vacuum pump, 43. Scanning voltage module, 44. Power supply module. DETAILED DESCRIPTION

[0048] The present invention will be further described below with reference to the accompanying drawings:

[0049] like Figure 1 The device, shown here, is a miniature handheld nanoparticle detection device comprising a miniature aerosol photocharger 1, a miniature disc aerosol precipitator 2, an aerosol hybrid condensation particle counter 3, and a main control module 4. While maintaining high detection accuracy for nanoparticles sized 10-200 nm, the device significantly reduces the overall size and weight of the device, ensuring its miniaturization. This allows for a handheld design and modular integration into other environmental monitoring instruments.

[0050] The aerosol charger 1 is a micro aerosol photocharger, which includes a charging shell 13 and a UV light-emitting device 15. An aerosol inlet 111 is provided on the charger cover 12. The sample gas flow flows into the aerosol photocharger 1 from the aerosol inlet 111. The metal electron collection net 16 is fixed inside the charging shell 13 and is located on both sides of the aerosol airflow with the UVC light-emitting device 15. The UVC light-emitting device 15 in the aerosol photocharger 1 emits UVC light. The collision of UVC light with the aerosol causes the aerosol to lose electrons. The escaping electrons are collected by the electron collection metal net 16, so that the ultrafine particles in the sample gas are positively charged, resulting in charged particles. The lower end of the charging shell 13 is sloped at 45 degrees, which can effectively reduce the loss of particles.

[0051] The aerosol precipitator 2 is a micro-disc aerosol precipitator, which includes a first metal plate 21, a second metal plate 27, a metal disc 25 and an electrically insulating gasket 23. The porous metal disc 25 is sandwiched between the symmetrically arranged first metal plate 21 and the second metal plate 27, and the electrically insulating gasket 23 is sleeved on the outer side of the middle section of the metal structure formed by the first metal plate 21, the metal disc 25 and the second metal plate 27. There is a gap between the first metal plate 21 and the metal disc 25, and there is a gap between the second metal plate 27 and the metal disc 25. The electrically insulating gasket 23 and the two gaps respectively form two identical flow chambers: a first flow chamber 24 and a second flow chamber 26. A plurality of through holes are opened on the metal disc 25, and the through holes are used to connect the first flow chamber 24 and the second flow chamber 26. The charged aerosol sample gas is introduced into the first flow chamber 24 through an inlet pipe 221 arranged in the middle of the first metal plate 21. The outlet pipe 222 connected to the second metal plate 27 serves as an aerosol flow outlet. The voltage can be applied via high-voltage wires connected to the outer edge of the central porous metal disk 25. The first and second metal plates 21, 27 can be electrically grounded or biased to separate potentials relative to the central metal disk 25, thereby establishing independent electric fields in each flow chamber. Aerosol enters the aerosol precipitator from the inlet tube 221, moves radially outward, passes through the through-holes in the metal disks, and converges radially to the outlet tube 222. When a fixed electric field is established in either chamber, the trajectories of the charged particles are deflected, and all particles with sufficiently large electrical mobility will be deposited on the first and second metal plates 21, 27, while those with lower mobility will partially or completely escape and leave the aerosol precipitator.

[0052] The aerosol hybrid condensation particle counter 3 includes a particle growth module 38 and a photoelectric detection module 39. The particle growth module 38 comprises an aerosol growth chamber housing, a heating kit 35, a cooling kit 32, a liquid reservoir 36, and a photoelectric detection chamber 312 mounted within the aerosol growth chamber housing 311. A photoelectric emitter 34 and a photoelectric detector 33 are mounted within the photoelectric detection chamber 312. Classified particles enter the aerosol hybrid condensation particle counter 3. After being cooled by the cooling kit 32, they mix with the working fluid vapor heated by the heating kit 35, causing condensation and growth of ultrafine particles. After growth, the particles enter the photoelectric detection module 39. The photoelectric emitter 34 emits light, some of which is blocked by the growing particles, while the remaining light is received by the photoelectric detector 33. The laser detector 33 on the photoelectric detection module 39 is connected to the main control module 4, and the photoelectric signal processing module of the main control module 4 receives the photoelectric signal. The main control module 4 includes a controller 41, a power module 44, a scanning voltage module 43, and a vacuum pump 42. The output end of the controller 41 is respectively connected to the input end of the high-voltage constant current module 45, the input end of the scanning voltage module 43 and the input end of the vacuum pump 42; the output end of the power supply module 44 is connected to the UV emitter 15; the scanning voltage module 43 is connected to the perforated metal disk 25 and the first metal plate 21 and the second metal plate 27; the output end of the vacuum pump 42 is connected to the sample gas outlet.

[0053] like Figure 3 As shown, the present invention also relates to a detection method for the above-mentioned micro handheld nano-particle detection device, which comprises the following steps:

[0054] (1) The controller 41 controls the sample gas flow through the vacuum pump 42 to enter the micro aerosol photocharger 1 through the air inlet of the radial inlet pipe 111 at a certain flow rate.

[0055] (2) The power module 44 controls the UVC light emitting device 15 in the aerosol photocharger to emit UVC light. The collision of the UVC light with the aerosol causes the aerosol to lose electrons. The escaped electrons are collected by the electron collecting metal mesh 16, so that the ultrafine particles in the sample gas are positively charged, thereby obtaining charged particles.

[0056] (3) Charged Aerosol The charged aerosol sample is introduced into the first flow chamber 24 by the central tube 221 of the top plate of the micro-disc aerosol precipitator 2, and the graded voltage can be applied by a high-voltage wire connected to the outer edge of the middle metal disk 25. The first metal plate 21 and the second metal plate 27 can be electrically grounded or biased to a separate potential relative to the middle disk, thereby establishing an independent electric field in any flow chamber. Charged particles enter the device from the central inlet tube 221, move radially outward, pass through the orifice, and radially converge to the opposite central outlet tube 222. When a fixed electric field is established on either chamber, the trajectory of the charged particles will be deflected. All particles with sufficiently large electrical mobility will be deposited on the plate, while those with lower mobility will partially or completely escape and leave the micro-disc aerosol precipitator 2.

[0057] (4) The ultrafine particles entering the aerosol hybrid condensation particle counter 3 from the micro-disc aerosol precipitator 2 are cooled by the refrigeration kit 32 and then mixed with the working fluid vapor heated by the heating kit 35, causing the ultrafine particles to condense and grow. After the particles grow, they enter the photoelectric detection module. The photoelectric emitter 34 emits light, some of which is blocked by the growing particles, and the remaining light is received by the photoelectric detector 33. The laser detector 33 on the photoelectric detection module is connected to the main control module 4. The photoelectric signal processing module of the main control module 4 receives and processes the photoelectric signal.

[0058] (5) When the sample gas flow rate is stable, the controller 41 changes the scanning voltage between the perforated metal disk 25 and the first metal plate 21 and the second metal plate 27 through the scanning voltage module 43, and detects the concentration of ultrafine particles at different particle sizes in a graded manner, and draws a particle size spectrum based on the concentration of ultrafine particles at different particle sizes.

[0059] The detection device described in the present invention is composed of an aerosol photocharger, an aerosol precipitator and an aerosol hybrid condensation particle counter with a microcurrent detection module. There are no similar products on the market. The charging modules of the current mainstream particle size spectrometers mostly use soft x-ray charging, diffusion charging and corona discharge. Compared with the traditional corona discharge, the UVC irradiation method adopted by the present invention has a higher charging efficiency for aerosols below 20nm, and it is stable in operation and not easy to produce ozone. Compared with UV (~5eV) irradiation, the diffusion charging rate under soft x-ray irradiation is improved. However, the high cost and limited service life of the soft x-ray light source make it difficult to use. The classification module of the current particle size spectrometer mostly uses an electromigration analyzer with sheath gas circulation, which has low penetration efficiency and large particle loss, and cannot be applied to aerosol classification detection in low concentration environments. Current low-concentration particle size spectrometers often use thermal conduction condensation particle counters for particle detection. These instruments have slow particle growth rates, resulting in large size and impracticality for miniaturization. The present invention, however, utilizes a hybrid condensation particle counter, which boasts rapid particle growth and minimal diffusion losses. In summary, the present invention enables monitoring of aerosol particle size distribution in the small 10nm to 200nm range in low-concentration environments, while maintaining a miniaturized design.

[0060] The above-described embodiments are merely descriptions of preferred implementations of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the scope of protection determined by the claims of the present invention.

Claims

1. A miniature handheld nano-particle detection device, characterized in that: The device comprises an aerosol photocharger, an aerosol precipitator and an aerosol mixed condensation particle counter which are arranged in sequence; The aerosol photocharger comprises a charged shell and a UVC light emitting device and a metal electron collecting net mounted on the charged shell; The aerosol precipitator includes a precipitator body and an electrically insulating gasket sleeved outside the precipitator body; the precipitator body includes a first metal plate, a metal disc, and a second metal plate arranged in sequence; the metal disc is provided with a plurality of through holes; a first gap is left between the first metal plate and the metal disc, and the gap and the inner wall of the electrically insulating gasket form a first flow chamber; a second gap is left between the second metal plate and the metal disc, and the gap and the inner wall of the electrically insulating gasket form a second flow chamber; the through holes are used to connect the first flow chamber with the second flow chamber; The aerosol hybrid condensation particle counter comprises a particle growth module and a photoelectric detection module which are arranged in sequence.

2. The detection device according to claim 1, characterized in that The charging housing has a charging aerosol inlet and a charging aerosol outlet coaxially arranged; The charged housing is provided with sealing rubber rings on both sides of the UVC light emitting device; The lower end of the charged shell is in a 45° slope.

3. The detection device according to claim 1, characterized in that The light emitted by the UVC light emitting device is perpendicular to the flow direction of the aerosol.

4. The detection device according to claim 1, characterized in that The metal electron collecting net is fixed inside the charged shell, and is located on both sides of the aerosol airflow with the UVC light emitting device.

5. The detection device according to claim 1, characterized in that An inlet pipe is provided on the first metal plate, and the inlet pipe is connected to the interior of the charged housing; An outlet pipe is provided on the second metal plate, and the outlet pipe is connected to the aerosol mixed condensation particle counter.

6. The detection device according to claim 1, characterized in that The metal plate is connected to high voltage electricity; The first metal plate and the second metal plate are grounded or biased to a separate potential relative to the metal plate, establishing an electric field in the first flow chamber and the second flow chamber respectively, forming a separate electric field that is not shared with other electronic equipment of the instrument.

7. The detection device according to claim 1, characterized in that The particle growth module includes an aerosol growth chamber shell and a liquid storage tank connected to the aerosol growth chamber shell; a heating kit, a cooling kit and an insulation kit are provided on the outer wall of the aerosol growth chamber shell; an aerosol air inlet, a first aerosol air outlet and a working liquid inlet are provided on the aerosol growth chamber shell; the first aerosol air inlet is connected to the outlet of the aerosol precipitator; the working liquid inlet is connected to the liquid storage tank; the heating kit is used to heat the working liquid to turn it into steam; the cooling kit is used to reduce the temperature of the aerosol; the insulation kit is used to insulate and allow the hot steam and the cold aerosol to be thermally mixed; the liquid storage tank is used to store the working liquid; The photoelectric detection module includes a photoelectric detection cavity and a photoelectric emitter and a photoelectric detector installed on the photoelectric detection cavity; a second aerosol outlet is opened on the photoelectric detection cavity.

8. The detection device according to claim 7, characterized in that The device also includes a main control module; The main control module includes a controller, a vacuum pump, a scanning voltage module, a power supply module and a photoelectric signal processing module; The output end of the controller is connected to the input end of the scanning voltage module and the input end of the vacuum pump respectively; The output end of the scanning voltage module is connected to the first metal plate, the second metal plate and the metal disk respectively; The photoelectric signal processing module is connected to the photoelectric detector; The vacuum pump is connected to the first aerosol outlet and the second aerosol outlet respectively.

9. The detection method of the detection device according to any one of claims 1 to 8, characterized in that: The method includes: (1) Aerosol sample gas enters the aerosol photocharger at a certain flow rate; (2) The UVC light emitting device in the aerosol photocharger emits UVC light. The UVC light collides with the aerosol, causing the aerosol to lose electrons. The escaped electrons are collected by the metal electron collection net, causing the ultrafine particles in the aerosol sample to be positively charged, thus obtaining charged particles. (3) Charged particles are introduced into the first flow chamber of the aerosol precipitator, and move radially outward, pass through the through holes on the metal plate, enter the second flow chamber, and radially converge to the outlet pipe; when a fixed electric field is established on the first flow chamber or the second flow chamber, the trajectory of the charged particles is deflected, and the charged particles that meet the set electric mobility are deposited on the first metal plate or the second metal plate, and the remaining charged particles will partially or completely leave the aerosol precipitator and enter the aerosol hybrid condensation particle counter; (4) The ultrafine particles entering the aerosol mixing condensation particle counter are mixed with the working fluid vapor cooled by the refrigeration kit and heated by the heating kit, thereby achieving condensation growth of the ultrafine particles; (5) When the condensed and grown ultrafine particles pass through the photoelectric detection cavity, the photoelectric detector will generate pulses. After the pulses are processed by the photoelectric signal processing module, the number of ultrafine particles of the corresponding particle size under the corresponding scanning voltage is obtained, and the concentration of ultrafine particles under the particle size is determined.

10. The detection method according to claim 9, characterized in that: The method further includes: When the sample gas flow rate is stable, the scanning voltage between the metal disk and the first metal plate and the second metal plate is changed to detect the concentration of ultrafine particles at different particle sizes in a graded manner, and a particle size spectrum is drawn according to the concentration of ultrafine particles at different particle sizes.

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