CN115000309A - Preparation method of tin oxide electron transport layer of perovskite solar cell - Google Patents

Abstract

The invention discloses a preparation method of a tin oxide electron transport layer of a perovskite solar cell, which comprises the following steps: loading solid pure tin metal particles into a metal molybdenum boat; opening the door of the vacuum chamber, and placing the molybdenum boat filled with pure tin metal particles into the water-cooled crucible; placing the substrate on a spin stand; closing the door of the vacuum chamber, and vacuumizing the vacuum chamber; introducing argon into the cathode tantalum tube to melt and evaporate pure tin metal particles; introducing oxygen into the vacuum chamber; the reaction produces tin oxide; opening the baffle plate, and finally depositing tin oxide on the substrate to form a metal oxide film; and carrying out ultraviolet ozone cleaning to obtain a finished product. The metal oxide film prepared by the invention has high transmittance, is uniform and has no holes, can be used as an electron transmission layer of the perovskite solar cell after being cleaned by ultraviolet ozone, does not need high-temperature annealing treatment, can realize conformal coverage of a large area or a textured substrate, and has low cost and strong repeatability.

Description

A kind of preparation method of tin oxide electron transport layer of perovskite solar cell

technical field

The invention relates to the field of optoelectronic materials, in particular to a preparation method of a tin oxide electron transport layer of a perovskite solar cell.

Background technique

A solar cell is a device that directly converts light energy into electrical energy through the photoelectric effect or photochemical reaction. In 1839, French physicist Becquerel discovered the photovoltaic effect, and in 1876, British scientist Adams and others discovered that when sunlight irradiated a selenium semiconductor, an electric current would be generated. The working principle of this photoelectric effect solar cell is that when sunlight shines on the semiconductor p-n junction region, it will excite the formation of hole-electron pairs (excitons). Under the action of the p-n junction electric field, the excitons are first separated into electrons and empty The holes are transported to the cathode and anode, respectively. Photogenerated holes flow to the p region, photogenerated electrons flow to the n region, and a current is formed when the circuit is turned on.

Perovskite solar cells are solar cells that use perovskite-type organic metal halide semiconductors as light-absorbing materials. They belong to the third generation of solar cells, also known as new concept solar cells.

In recent years, perovskite solar cells have developed rapidly, and the photoelectric conversion efficiency has increased from 3.8% in 2009 to 25.7% now. The electron transport layer is an essential part of high-efficiency perovskite solar cells, which plays the role of transporting electrons and hindering holes. In n-i-p planar perovskite solar cells, the quality of the electron transport layer also determines the growth quality of the upper perovskite layer. At present, the preparation method of tin oxide electron transport layer is mainly based on the solution method, but the solution method often requires high temperature annealing at 150 degrees Celsius and above to form a high-quality tin oxide electron transport layer, and the solution method often uses spin coating to form the film. Suitable for large area substrates and textured substrates. Therefore, it is necessary to design a preparation method for the tin oxide electron transport layer of perovskite solar cells.

SUMMARY OF THE INVENTION

In order to overcome the defects in the prior art, a preparation method of a tin oxide electron transport layer of a perovskite solar cell is provided.

The present invention is realized by the following scheme:

A preparation method of a tin oxide electron transport layer of a perovskite solar cell, the preparation method comprising the following steps:

Step 1, load the solid pure tin metal particles into the metal molybdenum boat;

Step 2. Open the door of the vacuum chamber, and place the molybdenum boat loaded with pure tin metal particles into the water-cooled crucible;

Step 3. Put the substrate on the rotating frame;

Step 4. Close the door of the vacuum chamber and evacuate the vacuum chamber;

Step 5. Pour argon gas into the cathode tantalum tube, and electrify the argon gas to ionize and ignite to generate an anion beam. The anion beam is directionally deflected and bombarded on the pure tin metal particles in the molybdenum boat under the action of the deflection magnetic field generated by the deflection coil. Melting and evaporating pure tin metal particles;

Step 6, feeding oxygen into the vacuum chamber; under the condition of electrification, part of the oxygen is ionized into active oxygen, and in the vacuum chamber, the active oxygen collides with the evaporated pure tin metal, and reacts to generate tin oxide;

Step 7, open the baffle, the tin oxide generated in the step 6 is finally deposited on the substrate to form a metal oxide film;

Step 8, taking out the metal oxide film deposited in the step 7, and cleaning with ultraviolet and ozone to obtain the finished product of the tin oxide electron transport layer of the perovskite solar cell.

In step 1, the purity of the solid pure tin metal particles is 99.99 wt %, and the solid pure tin metal particles are loaded at two-thirds of the height of the metal molybdenum boat.

In step 3, the substrate is a conductive glass or a conductive flexible substrate, and the substrate is cleaned by ultraviolet ozone for 30 minutes before being placed on the rotating rack.

In step 4, the vacuuming of the vacuum chamber is to pump the vacuum chamber to a pressure below 5×10 ⁻⁴ Pa.

In step 5, the flux of argon gas introduced into the cathode tantalum tube is 120-150 sccm.

In step 5, after the ionization and ignition of the argon gas, the flux of the argon gas in the cathode tantalum tube is 10-30 sccm.

In step 5, the energized current is 30-50A.

In step 6, the flux of the introduced oxygen is 40-60 sccm.

In step 8, the ultraviolet ozone cleaning is performed in an ultraviolet ozone cleaning machine for 10-20 minutes.

The beneficial effects of the present invention are:

The preparation method of the tin oxide electron transport layer of the perovskite solar cell of the present invention adopts pure tin metal as the target material, and the hollow anion plating method is applied, so that the evaporated tin metal reacts with oxygen more thoroughly. control the number of oxygen vacancies in the film. The prepared metal oxide film has high transmittance, uniformity and no holes, and can be used as the electron transport layer of perovskite solar cells after UV-ozone cleaning, without high-temperature annealing treatment, and can achieve conformal coverage of large-area or textured substrates , low cost and strong repeatability.

Description of drawings

FIG. 1 is a schematic diagram of a reactive hollow anion plating equipment for preparing a tin oxide film according to the present invention.

FIG. 2 is a scanning electron microscope image of the metal oxide thin film prepared by the present invention.

Detailed ways

The present invention is further described below:

As shown in Figure 1, a preparation method of a tin oxide electron transport layer of a perovskite solar cell, the preparation method comprises the following steps:

Step 1, the solid pure tin metal particles are loaded into the metal molybdenum boat (the specific structure and composition of the metal molybdenum boat are known technology, and will not be repeated here);

Step 2. Open the door of the vacuum chamber, and place the molybdenum boat loaded with pure tin metal particles into the water-cooled crucible;

Step 3. Put the substrate on the rotating frame;

Step 4. Close the door of the vacuum chamber and evacuate the vacuum chamber;

Step 5. Pour argon into the cathode tantalum tube, and electrify the argon to ionize and ignite to generate an anion beam (the specific process is: electrification to ionize the argon to generate a glow discharge, argon ions bombard the tantalum tube, and emit a large number of thermal electrons, The current increases, the voltage drops, and the glow discharge becomes arc discharge), and the anion beam is directionally deflected and bombarded on the pure tin metal particles in the molybdenum boat under the action of the deflection magnetic field generated by the deflection yoke, so that the pure tin metal particles are melted and evaporated;

Step 6, feeding oxygen into the vacuum chamber; under the condition of electrification, part of the oxygen is ionized into active oxygen, and in the vacuum chamber, the active oxygen collides with the evaporated pure tin metal, and reacts to generate tin oxide;

Step 7: Open the baffle, and the tin oxide generated in the step 6 is finally deposited on the substrate to form a metal oxide film; its microstructure is shown in FIG. 2 .

Step 8, taking out the metal oxide film deposited in the step 7, and cleaning with ultraviolet and ozone to obtain the finished product of the tin oxide electron transport layer of the perovskite solar cell.

In step 1, the purity of the solid pure tin metal particles is 99.99 wt %, and the solid pure tin metal particles are loaded at two-thirds of the height of the metal molybdenum boat.

In step 3, the substrate is a conductive glass or a conductive flexible substrate, and the substrate is cleaned by ultraviolet ozone for 30 minutes before being placed on the rotating rack.

In step 4, the vacuuming of the vacuum chamber is to pump the vacuum chamber to a pressure below 5×10 ⁻⁴ Pa.

In step 5, the flux of argon gas introduced into the cathode tantalum tube is 120-150 sccm.

In step 5, after the ionization and ignition of the argon gas, the flux of the argon gas in the cathode tantalum tube is 10-30 sccm.

In step 5, the energized current is 30-50A.

In step 6, the flux of the introduced oxygen is 40-60 sccm.

In step 8, the ultraviolet ozone cleaning is performed by using an ultraviolet ozone cleaning machine (the specific structure and principle of the ultraviolet ozone cleaning machine are well-known technologies, which will not be repeated here) for 10-20 minutes.

The preferred embodiments of the present invention are further described below:

Example 1

(1) Cleaning steps for conductive glass: ultrasonic cleaning with detergent and deionized water for 20 minutes, ultrasonic cleaning with deionized water for 20 minutes, ultrasonic cleaning with acetone for 20 minutes, alcohol ultrasonic cleaning for 20 minutes, and drying with nitrogen; for flexible linings To clean the bottom, use a dust-free cotton swab dipped in alcohol to gently wipe clean, and blow dry with nitrogen; both substrates were cleaned with an ultraviolet ozone cleaner for 20 minutes.

(2) Open the vacuum chamber door and place the substrate on the rotating frame;

(3) the solid pure tin metal particles are packed in the metal molybdenum boat;

(4) the molybdenum boat containing pure tin metal particles is placed in the water-cooled crucible;

(5) Close the door of the vacuum chamber, and pump the vacuum chamber to a pressure below 5×10 ^-4 Pa;

(6) Pour 120 sccm of argon gas into the cathode tantalum tube, and the current is 30 A to make the argon gas ionize and ignite. After stabilization, the argon gas flux is 10 sccm.

(7) Introduce 40sccm of oxygen into the vacuum chamber;

(8) Open the baffle, and the generated tin oxide is finally deposited on the substrate to form a 30nm metal oxide film;

(9) Take out the deposited sample, put it into an ultraviolet-ozone cleaning machine for 10 minutes, and obtain a tin oxide electron transport layer.

Example 2

(1) Cleaning steps for conductive glass: ultrasonic cleaning with detergent and deionized water for 20 minutes, ultrasonic cleaning with deionized water for 20 minutes, ultrasonic cleaning with acetone for 20 minutes, alcohol ultrasonic cleaning for 20 minutes, and drying with nitrogen; for flexible linings To clean the bottom, use a dust-free cotton swab dipped in alcohol to gently wipe clean, and blow dry with nitrogen; both substrates were cleaned with an ultraviolet ozone cleaner for 20 minutes.

(2) Open the vacuum chamber door and place the substrate on the rotating frame;

(3) the solid pure tin metal particles are packed in the metal molybdenum boat;

(4) the molybdenum boat containing pure tin metal particles is placed in the water-cooled crucible;

(5) Close the door of the vacuum chamber, and pump the vacuum chamber to a pressure below 5×10 ^-4 Pa;

(6) Pour 120 sccm of argon gas into the cathode tantalum tube, and the current is 40 A, so that the argon gas is ionized and ignited. After stabilization, the argon gas flux is 10 sccm.

(7) Introduce 40sccm of oxygen into the vacuum chamber;

(8) Open the baffle, and the generated tin oxide is finally deposited on the substrate to form a 30nm metal oxide film;

(9) Take out the deposited sample, put it into an ultraviolet-ozone cleaning machine for 10 minutes, and obtain a tin oxide electron transport layer.

Example 3

(1) Cleaning steps for conductive glass: ultrasonic cleaning with detergent and deionized water for 20 minutes, ultrasonic cleaning with deionized water for 20 minutes, ultrasonic cleaning with acetone for 20 minutes, alcohol ultrasonic cleaning for 20 minutes, and drying with nitrogen; for flexible linings To clean the bottom, use a dust-free cotton swab dipped in alcohol to gently wipe clean, and blow dry with nitrogen; both substrates were cleaned with an ultraviolet ozone cleaner for 20 minutes.

(2) Open the vacuum chamber door and place the substrate on the rotating frame;

(3) the solid pure tin metal particles are packed in the metal molybdenum boat;

(4) the molybdenum boat containing pure tin metal particles is placed in the water-cooled crucible;

(5) Close the door of the vacuum chamber, and pump the vacuum chamber to a pressure below 5×10 ^-4 Pa;

(6) Pour 120 sccm of argon gas into the cathode tantalum tube, and the current is 50 A to make the argon gas ionize and ignite. After stabilization, the argon gas flux is 10 sccm.

(7) Introduce 40sccm of oxygen into the vacuum chamber;

(8) Open the baffle, and the generated tin oxide is finally deposited on the substrate to form a 30nm metal oxide film;

(9) Take out the deposited sample, put it into an ultraviolet-ozone cleaning machine for 10 minutes, and obtain a tin oxide electron transport layer.

Example 4

(1) Cleaning steps for conductive glass: ultrasonic cleaning with detergent and deionized water for 20 minutes, ultrasonic cleaning with deionized water for 20 minutes, ultrasonic cleaning with acetone for 20 minutes, alcohol ultrasonic cleaning for 20 minutes, and drying with nitrogen; for flexible linings To clean the bottom, use a dust-free cotton swab dipped in alcohol to gently wipe clean, and blow dry with nitrogen; both substrates were cleaned with an ultraviolet ozone cleaner for 20 minutes.

(2) Open the vacuum chamber door and place the substrate on the rotating frame;

(3) the solid pure tin metal particles are packed in the metal molybdenum boat;

(4) the molybdenum boat containing pure tin metal particles is placed in the water-cooled crucible;

(5) Close the door of the vacuum chamber, and pump the vacuum chamber to a pressure below 5×10 ^-4 Pa;

(6) Pour 120 sccm of argon gas into the cathode tantalum tube, and the current is 40 A, so that the argon gas is ionized and ignited. After stabilization, the argon gas flux is 10 sccm.

(7) Introduce 50sccm of oxygen into the vacuum chamber;

(8) Open the baffle, and the generated tin oxide is finally deposited on the substrate to form a 30nm metal oxide film;

(9) Take out the deposited sample, put it into an ultraviolet-ozone cleaning machine for 10 minutes, and obtain a tin oxide electron transport layer.

Example 6

(1) Cleaning steps for conductive glass: ultrasonic cleaning with detergent and deionized water for 20 minutes, ultrasonic cleaning with deionized water for 20 minutes, ultrasonic cleaning with acetone for 20 minutes, alcohol ultrasonic cleaning for 20 minutes, and drying with nitrogen; for flexible linings To clean the bottom, use a dust-free cotton swab dipped in alcohol to gently wipe clean, and blow dry with nitrogen; both substrates were cleaned with an ultraviolet ozone cleaner for 20 minutes.

(2) Open the vacuum chamber door and place the substrate on the rotating frame;

(3) the solid pure tin metal particles are packed in the metal molybdenum boat;

(4) the molybdenum boat containing pure tin metal particles is placed in the water-cooled crucible;

(5) Close the vacuum chamber door, and pump the vacuum chamber to a pressure below 5×10 ^-4 ;

(6) Pour 120 sccm of argon gas into the cathode tantalum tube, and the current is 40 A, so that the argon gas is ionized and ignited. After stabilization, the argon gas flux is 10 sccm.

(7) feed 60sccm of oxygen into the vacuum chamber;

(8) Open the baffle, and the generated tin oxide is finally deposited on the substrate to form a 30nm metal oxide film;

(9) Take out the deposited sample, put it into an ultraviolet-ozone cleaning machine for 10 minutes, and obtain a tin oxide electron transport layer.

The electron transport layer described in this application is prepared by a method of reactive hollow anion plating to prepare a tin oxide thin film and is prepared by ultraviolet ozone treatment, and the thickness of the prepared thin film is about 30-40 nm. The invention provides a method for preparing a tin oxide thin film by using a method of reactive hollow anion plating, and combining with ultraviolet ozone treatment to obtain a uniform and dense tin oxide electron transport layer. The method has low temperature, little damage, and is suitable for complex substrates , low cost and so on.

Although the technical solutions of the present invention have been described and enumerated in more detail, it should be understood that, for those skilled in the art, modifications to the above-mentioned embodiments or equivalent alternative solutions are Obviously, these modifications or improvements made without departing from the spirit of the present invention belong to the scope of protection of the present invention.

Claims (9)

1. a preparation method of the tin oxide electron transport layer of perovskite solar cell, is characterized in that, this preparation method may further comprise the steps: Step 1, load the solid pure tin metal particles into the metal molybdenum boat; Step 2. Open the door of the vacuum chamber, and place the molybdenum boat loaded with pure tin metal particles into the water-cooled crucible; Step 3. Put the substrate on the rotating frame; Step 4. Close the door of the vacuum chamber and evacuate the vacuum chamber; Step 5. Pour argon gas into the cathode tantalum tube, and electrify the argon gas to ionize and ignite to generate an anion beam. The anion beam is directionally deflected and bombarded on the pure tin metal particles in the molybdenum boat under the action of the deflection magnetic field generated by the deflection coil. Melting and evaporating pure tin metal particles; Step 6, feeding oxygen into the vacuum chamber; under the condition of electrification, part of the oxygen is ionized into active oxygen, and in the vacuum chamber, the active oxygen collides with the evaporated pure tin metal, and reacts to generate tin oxide; Step 7, open the baffle, the tin oxide generated in the step 6 is finally deposited on the substrate to form a metal oxide film; Step 8, taking out the metal oxide film deposited in the step 7, and cleaning with ultraviolet and ozone to obtain the finished product of the tin oxide electron transport layer of the perovskite solar cell. 2. the preparation method of the tin oxide electron transport layer of a kind of perovskite solar cell according to claim 1, is characterized in that: in step 1, the purity of described solid pure tin metal particle is 99.99wt%, so The solid pure tin metal particles were loaded into a position two-thirds of the height of the metal molybdenum boat. 3. the preparation method of the tin oxide electron transport layer of a kind of perovskite solar cell according to claim 1, is characterized in that: in step 3, described substrate is conductive glass or conductive flexible substrate, described The substrates were subjected to UV ozone cleaning for 30 minutes before being placed on the spin rack. 4. the preparation method of the tin oxide electron transport layer of a kind of perovskite solar cell according to claim 1, is characterized in that: in step 4, described vacuum chamber is evacuated by vacuum chamber to 5 ×10 ^-4 Pa or less pressure. 5. the preparation method of the tin oxide electron transport layer of a kind of perovskite solar cell according to claim 1, is characterized in that: in step 5, in described in the cathode tantalum tube, the flux of passing argon gas It is 120～150sccm. 6. the preparation method of the tin oxide electron transport layer of a kind of perovskite solar cell according to claim 1, is characterized in that: in step 5, after described argon ionization glow, described in cathode The flux of argon gas in the tantalum tube is 10-30 sccm. 7. The preparation method of the tin oxide electron transport layer of a perovskite solar cell according to claim 1, wherein in step 5, the current size of the energization is 30-50A. 8 . The preparation method of the tin oxide electron transport layer of a perovskite solar cell according to claim 1 , wherein in step 6, the flux of the introduced oxygen is 40-60 sccm. 9 . 9. the preparation method of the tin oxide electron transport layer of a kind of perovskite solar cell according to claim 1, is characterized in that: in step 8, described ultraviolet ozone cleaning is to adopt ultraviolet ozone cleaning machine to clean 10- 20 minutes.

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