A perovskite work function regulator, a perovskite solar cell and a preparation method and application thereof
By using thiol compounds as work function modifiers for perovskites, the problems of complex and costly work function adjustment of perovskite materials in existing technologies have been solved, achieving high-efficiency photoelectric conversion and improved open-circuit voltage in perovskite solar cells.
Patent Information
- Application Number
- CN202211525254.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-11-30
- Publication Date
- 2026-02-03
- Estimated Expiration
- 2042-11-30
AI Technical Summary
Existing methods for adjusting the work function of perovskite materials require complex structures or are costly, have small adjustment ranges, and cannot selectively adjust the work function on the electron or hole side.
Thiol compounds are used as work function modifiers for perovskites. By mixing them with perovskite antisolvents and coating them onto the surface of the electrode layer, disulfides are formed through the oxidation process of thiol groups, thereby achieving a significant adjustment of the work function of the perovskite. Furthermore, the work function of the material is changed through Pb-S interactions.
Significant adjustment of the work function of perovskite was achieved, which improved the open-circuit voltage and photoelectric conversion efficiency of the battery, reduced material costs, and enhanced hole transport capability.
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Figure CN115768228B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of solar cell technology, and in particular to a perovskite work function modifier, a perovskite solar cell, its preparation method, and its application. Background Technology
[0002] Currently, global civilian and commercial photovoltaic modules are mainly based on crystalline silicon (c-Si) solar cells. Although c-Si solar cells have high efficiency and excellent stability, their production conditions are demanding and their raw materials and preparation costs are high, which limits their use.
[0003] In recent years, perovskite solar cells have gradually attracted attention. Perovskite has excellent photoelectric properties such as long carrier diffusion length, tunable optical bandgap, high molar extinction coefficient and bipolar transport. Furthermore, perovskite solar cell (PSC) devices have the advantages of being able to be prepared by all-solution method, simple manufacturing process, wide availability of raw materials and high photoelectric conversion efficiency, which creates conditions for large-scale production.
[0004] The structure of a perovskite solar cell can be simply divided into an "electron side" and a "hole side," and the work function of the perovskite significantly affects the charge transport process on each side. On the hole side, a larger work function of the perovskite is typically required, meaning the perovskite material exhibits p-type characteristics. This facilitates energy level matching with the hole transport material, accelerating hole transport and extraction. The work function of the perovskite material in a perovskite solar cell determines its energy level matching with the charge transport layer material, thus greatly influencing the cell's photoelectric conversion efficiency.
[0005] Therefore, adjusting the work function of perovskite materials helps to control device performance. However, existing technologies typically use p-type dopants to adjust the work function, such as 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanodimethyl-p-benzoquinone (F4TCNQ) and 1,3,4,5,7,8-hexafluorotetracyanonaphthoquinone dimethane (F6TCNNQ), which are added to the perovskite precursor solution. However, these p-type dopants are not only complex in structure and expensive, but also have low solubility in the perovskite precursor solution due to their complex structure, limiting their work function adjustment effect and resulting in a small adjustment range for the perovskite work function. Furthermore, directly adding the p-type dopant to the perovskite precursor solution results in a uniform distribution of the p-type dopant within the perovskite, making it impossible to selectively adjust the work function on the "electron side" or "hole side." Summary of the Invention
[0006] The technical problem to be solved by the present invention is to provide a perovskite work function modifier, a perovskite solar cell, a method for preparing the same, and its application, so as to solve the technical problems of existing perovskite material work function modulation methods requiring complex structures or high-cost materials, and having small work function modulation range.
[0007] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:
[0008] A perovskite work function modifier containing a thiol compound; said thiol compound having a thiol functional group.
[0009] Preferably, the thiol compound is one or more of alkyl thiols, aromatic thiols, and thiol amino compounds.
[0010] Preferably, the alkyl thiol is one or more of ethanethiol and ethylene dithiol;
[0011] The aromatic thiol is one or more of thiophenol, naphthiophenol, benzyl thiol, and phenylethyl thiol;
[0012] The thiol amino compound is one or more of cysteamine, cysteamine hydrochloride, and cysteine.
[0013] Preferably, the perovskite work function modifier further includes a perovskite antisolvent.
[0014] Preferably, the perovskite antisolvent is one or more of isopropanol, toluene, chlorobenzene, chloroform, acetone, and acetonitrile.
[0015] Preferably, the concentration of the thiol compound in the perovskite antisolvent is 0.01-0.1 mol / L.
[0016] This invention provides a method for preparing the perovskite work function modifier, comprising the following steps: dissolving a thiol compound in a perovskite antisolvent to obtain the product.
[0017] This invention also provides the application of the perovskite work function modifier in the fabrication of perovskite solar cells.
[0018] Preferably, the perovskite work function modifier is applied to perovskite solar cells prepared from lead-based perovskite precursor solutions.
[0019] Preferably, the solute in the lead-based perovskite precursor solution has the following general formula: APbX3;
[0020] Wherein, A can be one or more of methylamine, formamidinium, and cesium; X can be one or more of chlorine, bromine, and iodine.
[0021] The present invention also provides a perovskite solar cell, wherein the perovskite work function modifier is added.
[0022] The present invention also provides a method for preparing a perovskite solar cell, comprising at least the following steps: coating the perovskite work function modifier onto the surface of the electrode layer of the perovskite solar cell, and then allowing the volatile components of the perovskite work function modifier to volatilize, thereby obtaining the perovskite solar cell.
[0023] The above-described solution of the present invention has at least the following beneficial effects:
[0024] (1) The perovskite work function regulator of the present invention contains a thiol compound; the thiol compound has a thiol functional group. The perovskite work function regulator of the present invention uses a thiol compound with a simple structure, which is also lower in cost than the p-type dopant in the prior art. Furthermore, the perovskite work function regulator of the present invention is a small molecule containing a thiol functional group, which has higher compatibility with the perovskite precursor solution. At the same time, the thiol group can undergo an oxidation process in the air to generate the corresponding disulfide. This process achieves a significant adjustment of the perovskite work function and brings about an increase in the open-circuit voltage of the battery.
[0025] Specifically, the oxidation process of the thiol group is as follows:
[0026] 2R-SH+1 / 2O2→RSS-R+H2O, where R is an alkyl group, aromatic ring, or other similar group.
[0027] (2) In the perovskite work function regulator of the present invention, when the perovskite precursor solution is a lead-based perovskite precursor, the lead contained therein forms a coordination bond with the sulfur in the perovskite work function regulator. Through the strong interaction between Pb and S, the work function of the perovskite material can be changed, thereby achieving the regulation of the work function.
[0028] (3) A method for preparing a perovskite solar cell includes at least the following steps: coating the perovskite work function modifier onto the surface of the electrode layer of the perovskite solar cell, and then allowing the volatile components of the perovskite work function modifier to evaporate, thus obtaining the cell. In the prior art, p-type dopants are added to the perovskite precursor solution and uniformly distributed within the perovskite. This alters the work function of the perovskite on both the electron and hole sides to the same degree, making it impossible to selectively adjust the work function on either the "electron side" or the "hole side," resulting in their effects on device performance essentially canceling each other out. However, the perovskite work function modifier of this invention is directly introduced through a simple post-processing method, which can enrich the processed material on the hole side, enhancing the hole transport capability of that interface and improving device efficiency. Attached Figure Description
[0029] Figure 1This is a graph showing the Fermi level variation of the perovskite thin film sample in Example 1. Detailed Implementation
[0030] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.
[0031] Example 1
[0032] The perovskite work function modifier of this embodiment contains a thiol compound and a perovskite antisolvent; wherein the thiol compound is an alkyl thiol, specifically ethanethiol. The perovskite antisolvent is isopropanol. The concentration of the thiol compound in the perovskite antisolvent is 0.05 mol / L.
[0033] The preparation method of the perovskite work function modifier described in this embodiment includes the following steps: dissolving a thiol compound in a perovskite antisolvent to obtain the agent.
[0034] The perovskite solar cell of this embodiment contains the perovskite work function modifier described above.
[0035] The method for preparing the perovskite solar cell described in this embodiment includes at least: coating the perovskite work function modifier onto the surface of the electrode layer of the perovskite solar cell, and then allowing the volatile components of the perovskite work function modifier to evaporate, thereby obtaining the final product.
[0036] The method of coating the perovskite work function modifier on the electrode layer surface of the perovskite solar cell includes, but is not limited to, using a pipette to transfer the agent and then drop it onto the electrode layer surface.
[0037] As a specific implementation method of this embodiment, the fabrication method of the perovskite solar cell is as follows:
[0038] A dense titanium dioxide layer is sprayed onto FTO conductive glass. A mesoporous titanium dioxide layer is prepared by screen printing. A mesoporous insulating layer ZrO2 is prepared by screen printing. A carbon electrode layer is prepared by screen printing. Then, a perovskite precursor solution MAPbI3 is drop-coated onto the surface of the carbon electrode layer. After standing for 10 minutes, it is dried at 60°C to crystallize the perovskite. The perovskite work function modifier is then coated onto the surface of the carbon electrode layer. After the volatile components of the perovskite work function modifier evaporate, the product is obtained.
[0039] In MAPbI3, MA stands for melanamine.
[0040] It should be noted that the perovskite work function modifier of the present invention is applicable to, but is not limited to, printable mesoscopic perovskite solar cells, formal mesoporous perovskite solar cells, formal planar perovskite solar cells, inverted mesoporous perovskite solar cells, and inverted planar perovskite solar cells. In this embodiment, only a printable mesoscopic perovskite solar cell is used as an example. Those skilled in the art can also apply the perovskite work function modifier to perovskite solar cells prepared using other raw materials and methods.
[0041] Example 2
[0042] The perovskite work function modifier of this embodiment contains a thiol compound and a perovskite antisolvent; wherein the thiol compound is an aromatic thiol, specifically thiophenol. The perovskite antisolvent is toluene. The concentration of the thiol compound in the perovskite antisolvent is 0.01 mol / L.
[0043] The preparation method of the perovskite work function modifier described in this embodiment includes the following steps: dissolving a thiol compound in a perovskite antisolvent to obtain the agent.
[0044] The perovskite solar cell of this embodiment contains the perovskite work function modifier described above.
[0045] The method for preparing the perovskite solar cell described in this embodiment includes at least: coating the perovskite work function modifier onto the surface of the electrode layer of the perovskite solar cell, and then allowing the volatile components of the perovskite work function modifier to evaporate, thereby obtaining the final product.
[0046] The specific steps of the fabrication method of the perovskite solar cell are the same as those in Example 1.
[0047] Example 3
[0048] The perovskite work function modifier of this embodiment contains a thiol compound and a perovskite antisolvent; wherein the thiol compound is a thiolamine compound. The thiolamine compound is cysteine. The perovskite antisolvent is chlorobenzene. The concentration of the thiol compound in the perovskite antisolvent is 0.1 mol / L.
[0049] The preparation method of the perovskite work function modifier described in this embodiment includes the following steps: dissolving a thiol compound in a perovskite antisolvent to obtain the agent.
[0050] The perovskite solar cell of this embodiment contains the perovskite work function modifier described above.
[0051] The method for preparing the perovskite solar cell described in this embodiment includes at least: coating the perovskite work function modifier onto the surface of the electrode layer of the perovskite solar cell, and then allowing the volatile components of the perovskite work function modifier to evaporate, thereby obtaining the final product.
[0052] The specific steps of the fabrication method of the perovskite solar cell are the same as those in Example 1.
[0053] Example 4
[0054] The perovskite work function modifier of this embodiment contains a thiol compound and a perovskite antisolvent; wherein the thiol compound is an alkyl thiol, specifically ethylenedithiol. The perovskite antisolvent is chloroform. The concentration of the thiol compound in the perovskite antisolvent is 0.05 mol / L.
[0055] The perovskite work function modifier in this embodiment was prepared using the same method as in Example 1.
[0056] The perovskite solar cell of this embodiment incorporates the aforementioned perovskite work function modifier. The specific steps of the fabrication method for this perovskite solar cell are the same as in Example 1.
[0057] Example 5
[0058] The perovskite work function modifier of this embodiment contains a thiol compound and a perovskite antisolvent; wherein the thiol compound is an aromatic thiol. The aromatic thiol is naphthiophenol. The perovskite antisolvent is acetone. The concentration of the thiol compound in the perovskite antisolvent is 0.05 mol / L.
[0059] The perovskite work function modifier in this embodiment was prepared using the same method as in Example 1.
[0060] The perovskite solar cell of this embodiment incorporates the aforementioned perovskite work function modifier. The specific steps of the fabrication method for this perovskite solar cell are the same as in Example 1.
[0061] Example 6
[0062] The perovskite work function modifier of this embodiment contains a thiol compound and a perovskite antisolvent; wherein the thiol compound is an aromatic thiol. The aromatic thiol is a mixture of benzyl mercaptan and phenylethyl mercaptan in a 1:1 molar ratio. The perovskite antisolvent is acetonitrile. The concentration of the thiol compound in the perovskite antisolvent is 0.05 mol / L.
[0063] The perovskite work function modifier in this embodiment was prepared using the same method as in Example 1.
[0064] The perovskite solar cell of this embodiment incorporates the aforementioned perovskite work function modifier. The specific steps of the fabrication method for this perovskite solar cell are the same as in Example 1.
[0065] Example 7
[0066] The perovskite work function modifier of this embodiment contains a thiol compound and a perovskite antisolvent; wherein the thiol compound is a thiol amino compound. The thiol amino compound is a mixture of cysteine hydrochloride and cysteine in a 1:1 molar ratio. The perovskite antisolvent is a mixture of isopropanol and toluene in a 1:3 volume ratio. The concentration of the thiol compound in the perovskite antisolvent is 0.05 mol / L.
[0067] The perovskite work function modifier in this embodiment was prepared using the same method as in Example 1.
[0068] The perovskite solar cell of this embodiment incorporates the aforementioned perovskite work function modifier. The specific steps of the fabrication method for this perovskite solar cell are the same as in Example 1.
[0069] Example 8
[0070] The perovskite work function modifier in this embodiment is the same as that in Example 1, and is prepared using the same method as in Example 1.
[0071] The perovskite solar cell of this embodiment incorporates the aforementioned perovskite work function modifier. The specific steps of the fabrication method for the perovskite solar cell are the same as in Example 1, with the only difference being:
[0072] In the method for preparing the perovskite solar cell, the perovskite precursor solution is replaced by CH4N2PbCl3 instead of MAPbI3.
[0073] Example 9
[0074] The perovskite work function modifier in this embodiment is the same as that in Example 1, and is prepared using the same method as in Example 1.
[0075] The perovskite solar cell of this embodiment incorporates the aforementioned perovskite work function modifier. The specific steps of the fabrication method for the perovskite solar cell are the same as in Example 1, with the only difference being:
[0076] In the method for preparing the perovskite solar cell, the perovskite precursor solution is replaced with MASnI3 instead of MAPbI3.
[0077] Comparative Example 1
[0078] The preparation method of the perovskite solar cell in this comparative example is the same as that in Example 1, except that the perovskite work function modifier is not added.
[0079] Comparative Example 2
[0080] The preparation method of the perovskite solar cell in this comparative example is the same as that in Example 1, except that the perovskite work function modifier is not added, but a p-type dopant 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanodimethyl-p-benzoquinone (F4TCNQ) is used instead.
[0081] Comparative Example 3
[0082] The preparation method of the perovskite solar cell in this comparative example is the same as that in Example 8, except that the perovskite work function modifier is not added.
[0083] Comparative Example 4
[0084] The preparation method of the perovskite solar cell in this comparative example is the same as that in Example 9, except that the perovskite work function modifier is not added.
[0085] Effect Comparison
[0086] To verify the technical effect of the perovskite work function modifier described in this invention, the following experiments were conducted:
[0087] The perovskite work function modifiers prepared in Examples 1-9 were coated onto thin films with a thickness of 50 nm formed from the perovskite precursor solution to form perovskite thin film samples.
[0088] Thin films with a thickness of 50 nm formed from the perovskite precursor solutions described in Comparative Examples 1 and 3-4 were used as perovskite thin film samples.
[0089] In Comparative Example 2, a p-type dopant was added to the perovskite precursor solution, and the resulting thin film with a thickness of 50 nm was used as a perovskite thin film sample.
[0090] The perovskite thin film samples from Examples 1-9 and Comparative Examples 1-4 were placed for more than 48 hours to allow for complete oxidation, and the work function of the perovskite thin film samples was measured using ultraviolet photoelectron spectroscopy (UPS).
[0091] The Fermi level of the perovskite thin film sample in Example 1 was measured, such as... Figure 1The figure shows the Fermi level variation curves of the perovskite thin film sample in Example 1. The first curve represents the Fermi level test result of a 50 nm thick film formed from the perovskite precursor solution MAPbI3. The second curve represents the Fermi level test result of the perovskite thin film sample; that is, a perovskite work function modifier is coated onto a 50 nm thick film formed from the perovskite precursor solution MAPbI3 to form a perovskite thin film sample. The third curve represents the Fermi level test result of the oxidized perovskite thin film sample; that is, a perovskite thin film sample that has been left to oxidize sufficiently for more than 48 hours. Figure 1 It can be seen that the Fermi levels of the first, second, and third curves decrease sequentially. The magnitude of the change in the Fermi level corresponds to the change in the open-circuit voltage of the corresponding perovskite solar cell. The Fermi level test results of Examples 2-9 are the same as those of Example 1, all showing the phenomenon of the Fermi level of the first, second, and third curves decreasing sequentially. It is evident that the perovskite work function modifier can improve the open-circuit voltage in the initial stage of coating, and after sufficient oxidation, it will have a further improving effect on the open-circuit voltage.
[0092] The perovskite solar cells obtained in Examples 1-9 and Comparative Examples 1-4 were used as a light source with a solar simulator to test the open-circuit voltage and photoelectric conversion efficiency.
[0093] The results of the experiment are as follows:
[0094]
[0095] A comparison of Examples 1-7 with Comparative Examples 1-2 shows that the perovskite work function modifier described in this invention can significantly improve the work function regulation of perovskite and increase the open-circuit voltage of the cell, thereby greatly improving the photoelectric conversion efficiency of the obtained perovskite solar cell. A comparison of Example 8 with Comparative Example 3, Example 9 with Comparative Example 4, and Examples 1-7 with Comparative Examples 1-2 shows that the perovskite work function modifier described in this invention has a significant regulating effect on perovskite solar cells prepared from lead-based perovskite precursor solutions.
[0096] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. Application of perovskite work function modifier in the fabrication of perovskite solar cells prepared from lead-based perovskite precursor solution, wherein the solute in the lead-based perovskite precursor solution is MAPbI3; The perovskite work function modifier contains a thiol compound and a perovskite antisolvent; the thiol compound has a thiol functional group; The thiol compounds are one or more of alkyl thiols and aromatic thiols; The perovskite antisolvent is one or more of isopropanol, toluene, chlorobenzene, chloroform, acetone, and acetonitrile; The concentration of the thiol compound in the perovskite antisolvent is 0.01-0.1 mol / L; The perovskite work function modifier is used to adjust the work function of perovskite solar cells.
2. In the application according to claim 1, the alkyl thiol is one or more of ethanethiol and ethylene dithiol; The aromatic thiol is one or more of thiophenol, naphthiophenol, benzyl thiol, and phenylethyl thiol.
3. A perovskite solar cell prepared from a lead-based perovskite precursor solution, characterized in that, The solution contains a perovskite work function modifier, and the solute in the lead-based perovskite precursor solution is MAPbI3. The perovskite work function modifier contains a thiol compound and a perovskite antisolvent; the thiol compound has a thiol functional group; The thiol compounds are one or more of alkyl thiols and aromatic thiols; The perovskite antisolvent is one or more of isopropanol, toluene, chlorobenzene, chloroform, acetone, and acetonitrile; The concentration of the thiol compound in the perovskite antisolvent is 0.01-0.1 mol / L; The perovskite work function modifier is used to adjust the work function of perovskite solar cells.
4. A method for preparing a perovskite solar cell using a lead-based perovskite precursor solution as described in claim 3, characterized in that, The process includes at least the following steps: coating a perovskite work function modifier onto the surface of the electrode layer of a perovskite solar cell, and then allowing the volatile components of the perovskite work function modifier to evaporate, thus obtaining the desired product.