Disclosure of Invention
The invention aims to provide a flexible perovskite quantum dot film-gallium arsenide heterojunction battery and a preparation method thereof, so that the high efficiency of the battery is obtained, the application of gallium arsenide materials is reduced, and the cost is reduced.
The invention provides a flexible perovskite quantum dot film-gallium arsenide heterojunction battery, which comprises:
a substrate;
the substrate is sequentially provided with a back electrode layer, a back field layer, a P-type gallium arsenide thin film layer, a perovskite quantum dot thin film layer, an N-type transparent conductive window layer and a front electrode layer.
The flexible perovskite quantum dot thin film-gallium arsenide heterojunction battery as described above, wherein preferably, a down-conversion luminescence layer is further included between the N-type transparent conductive window layer and the front electrode layer.
The flexible perovskite quantum dot thin film-gallium arsenide heterojunction battery as described above, wherein preferably, a graphene thin film layer is further included between the P-type gallium arsenide thin film layer and the perovskite quantum dot thin film layer.
The flexible perovskite quantum dot thin film-gallium arsenide heterojunction battery as described above, wherein preferably, the down-conversion luminescent layer is a rare earth ion doped material based on fluoride, oxide or sulfide.
The flexible perovskite quantum dot thin film-gallium arsenide heterojunction battery as described above, wherein preferably the down-conversion luminescent layer is SiO with YAG: Ce3+ (Ga, Pr)2A film.
The flexible perovskite quantum dot thin film-gallium arsenide heterojunction battery as described above, wherein preferably the perovskite quantum dot thin film layer comprises organic-inorganic hybrid perovskite quantum dots or inorganic perovskite quantum dots or a combination of organic-inorganic hybrid perovskite quantum dots and inorganic perovskite quantum dots.
The flexible perovskite quantum dot thin film-gallium arsenide heterojunction battery as described above, wherein preferably the N-type transparent conductive window layer comprises TiO2、ZnO、ZnS、SnO2、In2O3、WS2One or a combination of two or more of them.
The invention also provides a preparation method of the flexible perovskite quantum dot film-gallium arsenide heterojunction battery, wherein the preparation method comprises the following steps:
preparing a sacrificial layer on a substrate;
preparing a P-type gallium arsenide film layer on the sacrificial layer;
sequentially preparing a back field layer and a back electrode layer on the P-type gallium arsenide film layer;
arranging a substrate on the back electrode layer, etching the sacrificial layer, and separating the P-type gallium arsenide film layer from the substrate;
preparing a perovskite quantum dot thin film layer on the P-type gallium arsenide thin film layer;
preparing an N-type transparent conductive window layer on the perovskite quantum dot thin film layer;
and preparing a front electrode layer on the N-type transparent conductive window layer.
The method for preparing the flexible perovskite quantum dot thin film-gallium arsenide heterojunction battery preferably further comprises, before preparing the perovskite quantum dot thin film layer on the P-type gallium arsenide thin film layer:
and preparing a graphene film on the P-type gallium arsenide film layer.
The preparation method of the flexible perovskite quantum dot thin film-gallium arsenide heterojunction battery, preferably, the preparation of the perovskite quantum dot thin film layer on the graphene thin film specifically comprises:
dissolving cesium carbonate and oleic acid in a first set amount of octadecene, and reacting at a first set temperature and under the protection of nitrogen for a first time length to obtain an oleate containing cesium ions;
maintaining the lead bromide and a second set amount of octadecene at a second set temperature for a second period of time;
adding oleylamine and oleic acid into the octadecene with the second set amount, and raising the second set temperature to a third set temperature after the lead bromide is completely dissolved;
adding said cesium ion-containing oleate to said second set amount of a mixture of octadecene, oleylamine and oleic acid and holding for a third period of time;
cooling the reacted mixture in an ice bath to obtain a mixture solution;
and spin-coating the mixture solution on the graphene film, and carrying out heat treatment at a fourth set temperature for a fourth time.
The preparation method of the flexible perovskite quantum dot thin film-gallium arsenide heterojunction battery, preferably, the preparation of the perovskite quantum dot thin film layer on the graphene thin film specifically comprises:
dissolving methyl ammonium bromide, lead bromide, octylamine and oleic acid in dimethylformamide to form a precursor solution;
adding the precursor solution into toluene to obtain a mixed solution;
and spin-coating the mixed solution on the graphene film, carrying out heat treatment at a fifth set temperature, and keeping for a fifth time.
The preparation method of the flexible perovskite quantum dot thin film-gallium arsenide heterojunction battery is described above, wherein preferably, a down-conversion luminescent layer is prepared on the N-type transparent conductive window layer;
and preparing a front electrode layer on the down-conversion luminescent layer.
The preparation method of the flexible perovskite quantum dot thin film-gallium arsenide heterojunction battery, preferably, the step of preparing the down-conversion light-emitting layer on the N-type transparent conductive window layer specifically includes:
preparing a first mixed solution consisting of deionized water and absolute ethyl alcohol, and adjusting the pH value of the first mixed solution to be acidic;
adding a set amount of YAG: Ce3+ (Ga, Pr) powder to the first mixed solution to obtain a second mixed solution;
adding a set amount of ethyl orthosilicate into the second mixed solution, and continuously stirring for a sixth time to obtain a spin-on solution;
and placing the spin-coating liquid in a drying box and keeping the spin-coating liquid at a sixth set temperature for a seventh time.
According to the flexible perovskite quantum dot film-gallium arsenide heterojunction battery and the preparation method thereof, the perovskite quantum dot film-gallium arsenide heterojunction is formed, so that the use amount of rare material gallium arsenide is reduced, the cost is reduced, and the battery efficiency is improved. Furthermore, by arranging the down-conversion light-emitting layer, the ultraviolet light is converted into the visible light, the corresponding spectrum range of the solar cell is widened, and the photoelectric performance of the cell is improved.
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative only and should not be construed as limiting the invention.
As shown in fig. 1, an embodiment of the present invention provides a flexible perovskite quantum dot thin film-gallium arsenide heterojunction battery, which includes a substrate 100, and a back electrode layer 200, a back field layer 300, a P-type gallium arsenide thin film layer 400, a perovskite quantum dot thin film layer 600, an N-type transparent conductive window layer 700, and a front electrode layer 900 are sequentially disposed on the substrate 100. Therefore, by forming the perovskite quantum dot film-gallium arsenide heterojunction, the consumption of rare material gallium arsenide is reduced, the cost is reduced, and the efficiency of the battery is improved.
Further, the heterojunction cell also includes a down-conversion light emitting layer 800 between the N-type transparent conductive window layer 700 and the front electrode layer 900. The down-conversion light-emitting layer 800 can convert the emitted photon energy to be lower than the absorbed photon energy, that is, convert the short wavelength light to the long wavelength light, so as to absorb the ultraviolet light and emit the visible light, thereby widening the corresponding spectrum range of the solar cell and improving the photoelectric performance of the cell.
Further, in order to modify the interface between the perovskite quantum dot thin film layer and the P-type gallium arsenide thin film layer to form good interface contact, a graphene thin film layer 500 may be prepared between the P-type gallium arsenide thin film layer and the perovskite quantum dot thin film layer.
The down-conversion luminescent layer 800 may be a material doped with rare earth ions and having fluoride, oxide or sulfide as a matrix. Specifically, the down-conversion luminescent layer 800 is Silica (SiO) with YAG: Ce3+ (Ga, Pr)2) A film. Ce3+ (Ga, Pr) is a fluorescent material, the absorption spectrum of the fluorescent material is 256nm, and the fluorescent material has two emission peaks of 532nm and 610nm and can be effectively utilized in the absorption spectrum range of gallium arsenide and perovskite quantum dots.
It is noted that the perovskite quantum dot thin film layer 600 may include organic-inorganic hybrid perovskite quantum dots or inorganic perovskite quantum dots or a combination of organic-inorganic hybrid perovskite quantum dots and inorganic perovskite quantum dots.
In particular, the N-type transparent conductive window layer 700 may include TiO2、ZnO、ZnS、SnO2、In2O3、WS2Preferably, the N-type transparent conductive window layer 700 includes ZnO, and in order to improve the conductivity and stability of the N-type transparent conductive window layer 700 and reduce the resistivity, the ZnO may be doped with aluminum.
Specifically, the materials of the front electrode layer 900 and the back electrode layer 200 may include one or a combination of two or more of gold, silver, platinum, aluminum, nickel, copper, titanium, chromium, and tin, and preferably, the materials of the front electrode layer 900 and the back electrode layer 200 are both copper.
As shown in fig. 2, an embodiment of the present invention further provides a method for manufacturing a flexible perovskite quantum dot thin film-gallium arsenide heterojunction battery, wherein, in a first embodiment of the manufacturing method, the method includes the following steps:
step S101, preparing a sacrificial layer on the substrate. The sacrificial layer is an aluminum arsenide (AlAs) sacrificial layer, the thickness of the sacrificial layer is 5-8 nm, and in order to improve the stripping corrosion rate of the battery epitaxial layer, the thickness of the sacrificial layer is preferably 6 nm.
And S102, preparing a P-type gallium arsenide film layer on the sacrificial layer. Wherein, the thickness of the P-type gallium arsenide film is 950-1050 nm, preferably 1000 nm.
Step S103, preparing a back field layer and a back electrode layer on the P-type gallium arsenide film layer in sequence. The back field layer is made of aluminum gallium arsenide (AlGaAs), and the thickness of the back field layer is 9-11 nm, preferably 10 nm.
It should be noted that the back electrode layer can be prepared on the back field layer by magnetron sputtering (PVD).
Wherein, when the back electrode layer is prepared by magnetron sputtering technology, the sputtering target can be a high-purity oxygen-free copper target with the purity of 99.99 percent, the gas source is high-purity argon with the purity of 99.999 percent, the argon flow is 25 sccm-40 sccm, the sputtering power is 100W-150W, the sputtering pressure is 0.1 Pa-0.5 Pa, the background vacuum degree of the vacuum chamber is 10-4Pa~10-7Pa。
And step S104, arranging a substrate on the back electrode layer, etching the sacrificial layer, and separating the P-type gallium arsenide film layer from the substrate.
The substrate is stripped through an epitaxial layer stripping technology, and a composite structure formed by the back electrode layer, the back field layer and the P-type gallium arsenide thin film layer is transferred to the substrate. Wherein, when the epitaxial layer stripping technology is utilized to strip the P-type gallium arsenide film layer, the used corrosive liquid is hydrofluoric acid. The material of the base may be PET.
It should be noted that the P-type gaas film layer, the back field layer, and the sacrificial layer can be prepared by vapor phase epitaxy. When the P-type gallium arsenide thin film layer, the back field layer and the sacrificial layer are prepared by using a vapor phase epitaxy growth technology (MOCVD), the process temperature can be 600-800 ℃, the growth speed can be 0.005-0.03 μm/min, and the ratio of the molar flow of the V-group gas source to the molar flow of the III-group gas source can be 50-80.
And S105, preparing a perovskite quantum dot thin film layer on the P-type gallium arsenide thin film layer. The thickness of the perovskite quantum dot film layer is 600-700 nm, and 650nm is preferred.
And S106, preparing an N-type transparent conductive window layer on the perovskite quantum dot thin film layer. The N-type transparent conductive window layer is made of zinc oxide (ZnO), and in order to improve the conductivity and stability of the N-type transparent conductive window layer and reduce the resistivity, aluminum can be doped in the ZnO. Wherein the thickness of the N-type transparent conductive window layer is 100-200 nm, preferably 150 nm.
Wherein, an N-type transparent conductive window layer can be prepared on the perovskite quantum dot thin film layer by a magnetron sputtering technology. When the magnetron sputtering technology is used for preparing the N-type transparent conductive window layer, the sputtering target can be ZnO to Al2O3The substrate temperature can be 90-110 ℃, the gas source is argon, the argon flow is 40-60 sccm, the reaction pressure is 0.1-0.7 Pa, and the background vacuum degree of the vacuum chamber is 10-4Pa~10-7Pa。
And S107, preparing a front electrode layer on the N-type transparent conductive window layer.
Further, in order to modify the interface between the perovskite quantum dot thin film layer and the P-type gallium arsenide thin film layer to form good interface contact, before the perovskite quantum dot thin film layer is prepared on the P-type gallium arsenide thin film layer, the method may further include the following steps:
and S10, preparing a graphene film layer on the P-type gallium arsenide film layer.
In particular, the graphene film may be disposed by a thermal lift-off tape technique. Wherein, set up the graphite alkene thin layer through hot stripping tape technique and specifically include:
step S1, growing a graphene thin film on a copper (Cu) foil by a Chemical Vapor Deposition (CVD) method.
Step S2, the adhesive tape TRT with the peeling layer removed is smoothly and closely attached to the graphene film grown on the Cu foil.
Step S3, using ammonium sulfate ((NH)4)2SO4) And corroding the copper foil by using the solution, and cleaning and airing.
And step S4, tightly attaching the TRT-graphene and the P-type gallium arsenide film, baking to a temperature higher than the thermal peeling temperature, and enabling the adhesive tape to spontaneously fall off to complete the setting of the graphene film.
As shown in fig. 3, in a second embodiment of the manufacturing method, the following steps are included:
step S201, a sacrificial layer is prepared on the substrate.
Step S202, preparing a P-type gallium arsenide thin film layer on the sacrificial layer.
Step S203, a back field layer and a back electrode layer are sequentially prepared on the P-type gallium arsenide film layer.
And S204, arranging a substrate on the back electrode layer, etching the sacrificial layer, and separating the P-type gallium arsenide film layer from the substrate.
And S205, preparing a perovskite quantum dot thin film layer on the P-type gallium arsenide thin film layer.
And S206, preparing an N-type transparent conductive window layer on the perovskite quantum dot thin film layer.
And S207, preparing a down-conversion luminescent layer on the N-type transparent conductive window layer.
Step S208, preparing a front electrode layer on the down-conversion light emitting layer. In particular, laser drilling and electrochemical processes may be used to fabricate the front electrode layer on the down-converting light-emitting layer. Wherein the down-conversion light-emitting layer and the front electrode layer are of graphical structures.
As shown in fig. 4, in an embodiment, the preparation of the perovskite quantum dot thin film layer on the graphene thin film specifically includes the following steps:
step S301, dissolving cesium carbonate and oleic acid in a first set amount of octadecene, and reacting for a first time at a first set temperature under the protection of nitrogen to obtain a solution containing cesium and oleic acidCesium ion (Cs)+) Oleate of (a). Wherein, the first set temperature can be 100-160 ℃, preferably 150 ℃, and the first time length can be 40-80 min, preferably 60 min. Wherein, the first setting amount can be determined according to the requirement in actual work.
Step S302, holding lead bromide and a second set amount of octadecene at a second set temperature for a second period of time. Wherein the second set temperature can be 100-140 ℃, preferably 120 ℃, and the second time length can be 40-80 min, preferably 60 min. Wherein the second set amount may be determined according to a demand in an actual work.
And step S303, adding oleylamine and oleic acid into a second set amount of octadecene, and raising the second set temperature to a third set temperature after completely dissolving lead bromide. The third set temperature may be 135 to 150 ℃, and is preferably 140 ℃.
Step S304, adding cesium-containing ions (Cs) to a second set amount of a mixture of octadecene, oleylamine and oleic acid+) And held for a third period of time. Wherein the third time period may be 4s to 10s, preferably 5 s.
Step S305, the reacted mixture was placed in an ice bath to be cooled, to obtain a mixture solution.
And S306, spin-coating the mixture solution on the graphene film, and performing heat treatment at a fourth set temperature for a fourth time. The fourth set temperature may be 90 to 105 ℃, preferably 100 ℃, and the fourth time may be 25 to 35min, preferably 30 min.
As shown in fig. 5, in another embodiment, the preparation of the perovskite quantum dot thin film layer on the graphene thin film specifically includes the following steps:
step S401, methyl ammonium bromide, lead bromide, octylamine and oleic acid are dissolved in dimethylformamide to form a precursor solution.
Step S402, adding the precursor solution into toluene, and intensively stirring to obtain a mixed solution.
Step S403, spin-coating the mixed solution on the graphene film, and performing heat treatment at a fifth set temperature for a fifth time. Wherein the fifth set temperature can be 90-105 ℃, preferably 100 ℃, and the fifth time can be 25-35 min, preferably 30 min.
It should be noted that the mixed solution can be observed to see if orange-yellow micron-sized CH appears at the bottom3NH3PbBr3And precipitating to judge whether the mixed solution is fully mixed and can be used, and if the precipitate appears, the mixed solution can be spin-coated on the graphene film and subsequent operation is carried out.
In yet another embodiment, as shown in fig. 6, the preparing of the down-conversion luminescent layer on the N-type transparent conductive window layer may specifically include:
step S501, preparing a first mixed solution composed of deionized water and absolute ethyl alcohol, and adjusting the pH value of the first mixed solution to be acidic.
Step S502, adding a predetermined amount of uniformly ground YAG Ce3+ (Ga, Pr) powder to the first mixed solution to obtain a second mixed solution. The amount of the YAG: Ce3+ (Ga, Pr) powder after grinding can be determined according to the requirements in actual work.
And step S503, adding a set amount of ethyl orthosilicate into the second mixed solution, and continuously stirring for a sixth time to obtain the spin-on liquid. The sixth time period can be 6-8 h, and is preferably 7 h.
And step S504, placing the spin coating liquid in a drying box, and keeping the spin coating liquid at a sixth set temperature for a seventh time. Wherein the sixth set temperature may be 120-150 ℃, preferably 130 ℃, and the seventh time period may be 5-15 min, preferably 10 min.
According to the flexible perovskite quantum dot film-gallium arsenide heterojunction battery and the preparation method thereof, the perovskite quantum dot film-gallium arsenide heterojunction is formed, so that the use amount of rare material gallium arsenide is reduced, the cost is reduced, and the battery efficiency is improved. Furthermore, by arranging the down-conversion light-emitting layer, the ultraviolet light is converted into the visible light, the corresponding spectrum range of the solar cell is widened, and the photoelectric performance of the cell is improved.
The construction, features and functions of the present invention are described in detail in the embodiments illustrated in the drawings, which are only preferred embodiments of the present invention, but the present invention is not limited by the drawings, and all equivalent embodiments modified or changed according to the idea of the present invention should fall within the protection scope of the present invention without departing from the spirit of the present invention covered by the description and the drawings.