Preparation of organic photovoltaic heterojunction nanoparticles and application of organic photovoltaic heterojunction nanoparticles in photocatalytic ammonia production
By preparing organic photovoltaic heterojunction nanoparticles, the problem of insufficient near-infrared light response of graphitic carbon nitride and perovskite in photocatalytic nitrate reduction reaction was solved, realizing efficient photocatalytic nitrate reduction to ammonia synthesis and improving photocatalytic efficiency and stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-18
- Publication Date
- 2026-03-24
AI Technical Summary
Existing graphitic carbon nitride (g-C3N4) and perovskite exhibit weak spectral response in the near-infrared region during photocatalytic nitrate reduction, leading to a waste of near-infrared photons in the solar spectrum and limiting the improvement of photocatalytic efficiency.
Organic photovoltaic heterojunction nanoparticles were prepared by using PM6 and Y6 or compound I as donors and acceptors, combined with Pt loading, to optimize exciton diffusion length and photogenerated charge generation and transport. Nanoparticles were formed using microemulsion method and photodeposition technology to enhance near-infrared light response and exciton lifetime.
It significantly improves the efficiency of photocatalytic reduction of nitrate to ammonia, achieving efficient photon-charge conversion and catalytic performance, and enhancing catalytic activity and stability.
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Figure CN121715215A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application relates to the field of photocatalysis, in particular to a preparation method of an organic photovoltaic heterojunction nanoparticle and application of the organic photovoltaic heterojunction nanoparticle in photocatalytic ammonia synthesis. BACKGROUND
[0002] As an important chemical raw material and a zero-carbon energy carrier with great potential, ammonia is still highly dependent on the high-energy-consumption Haber-Bosch method in existing industrial synthesis, which consumes a large amount of energy and is accompanied by a large amount of carbon dioxide emission. In this context, the photocatalytic nitrate reduction synthesis of ammonia technology emerges as a double-function strategy.
[0003] At present, graphite phase carbon nitride (g-C3N4) and perovskite developed through element doping, heterojunction construction, morphology regulation, surface modification and other strategies exhibit good potential in the photocatalytic nitrate reduction reaction, but the inherent material properties still significantly restrict the performance improvement: the spectral response to the near-infrared region is generally weak, causing a serious waste of photons in the near-infrared part of the solar spectrum, which becomes one of the key bottlenecks restricting the overall photocatalytic efficiency improvement. SUMMARY
[0004] The application provides a preparation method of an organic photovoltaic heterojunction nanoparticle and application of the organic photovoltaic heterojunction nanoparticle in photocatalytic ammonia synthesis.
[0005] The application provides an organic photovoltaic heterojunction nanoparticle, which comprises a carrier and Pt loaded on the carrier. The raw material of the organic photovoltaic heterojunction nanoparticle comprises a donor and an acceptor. The donor comprises PM6, and the acceptor comprises Y6 and / or a compound with the structure shown in Formula I. Formula I.
[0006] Preferably, the preparation method of the compound with the structure shown in Formula I comprises the following steps: The compound with the structure shown in Formula 1, 2-(5,6-dichloro-2,3-dihydro-3-oxo-1H-inden-1-ylidene) malononitrile, pyridine and an organic solvent are mixed to perform a condensation reaction, so that the compound with the structure shown in Formula I is obtained.
[0007] Preferably, the molar ratio of the compound with the structure shown in Formula 1 to 2-(5,6-dichloro-2,3-dihydro-3-oxo-1H-inden-1-ylidene) malononitrile is 7:19.
[0008] Preferably, the use amount ratio of the compound with the structure shown in Formula 1 to the organic solvent is 7 mol:3 L; and the organic solvent comprises chloroform. The volume ratio of the pyridine and the organic solvent is 1:60.
[0009] Preferably, the temperature of the condensation reaction is 55-70℃, and the time is 9-12h.
[0010] Preferably, the mass ratio of the donor and the acceptor is 0-10:10-0.
[0011] Preferably, the mass of the platinum is 5-25% of the mass of the organic photovoltaic heterojunction nanoparticle.
[0012] The application also provides a preparation method of the organic photovoltaic heterojunction nanoparticle. The organic solution of the donor, the organic solution of the acceptor and the aqueous solution of the surfactant are mixed to form a microemulsion; After the organic solvent in the microemulsion is removed, the aqueous solution of chloroplatinic acid is mixed to perform photodeposition, so as to obtain the organic photovoltaic heterojunction nanoparticle.
[0013] Preferably, the surfactant includes sodium dodecyl sulfate. The concentration of the surfactant in the solution of the surfactant is 0.5wt%. The concentration of the donor in the organic solution of the donor is 0.5 mg / mL. The concentration of the acceptor in the organic solution of the acceptor is 0.5 mg / mL. The volume ratio of the aqueous solution of the surfactant to the total volume of the organic solution of the donor and the organic solution of the acceptor is 1:1. The light intensity of the photodeposition is 100 mW·cm -2 , and the time is 6-8h.
[0014] The application also provides an application of the organic photovoltaic heterojunction nanoparticle as a catalyst in photocatalytic reduction of nitrate to synthesize ammonia.
[0015] The organic photovoltaic heterojunction nanoparticle formed after the donor and the acceptor react can improve the exciton diffusion length, realize efficient dissociation of photo-generated excitons, effectively promote the generation and transmission of photo-generated charges, and improve the photon-charge conversion efficiency and catalytic performance.
[0016] In addition, the application obtains a 1Br4Cl acceptor material (a compound of the structure shown in Formula I) by two-dimensionally conjugated extension of Y6 and fine modification in combination with peripheral halogen atoms, which is significantly improved in near-infrared light response, exciton lifetime, intermolecular stacking strength and crystalline order, and the above characteristics collectively optimize the photo-induced charge generation and separation efficiency of the nanoparticles, thereby showing significantly stronger catalytic activity in the reaction of photocatalytic reduction of nitrate to synthesize ammonia. BRIEF DESCRIPTION OF DRAWINGS
[0017] Figure 1 NMR spectra of 1Br4Cl; Figure 2 High-resolution transmission electron microscopy images of PM6: Y6 nanoparticles, PM6: 1Br4Cl nanoparticles and Pt-loaded PM6: 1Br4Cl nanoparticles; Figure 3 UV-visible absorption spectra of PM6: Y6 nanoparticles and PM6: 1Br4Cl nanoparticles prepared in Examples 1-2; Figure 4 Photocatalytic experimental results. DETAILED DESCRIPTION
[0018] The application provides an organic photovoltaic heterojunction nanoparticle, which comprises a carrier and Pt loaded on the carrier. The raw material of the organic photovoltaic heterojunction nanoparticle comprises a donor and an acceptor. The donor comprises PM6, and the acceptor comprises Y6 and / or a compound of the structure shown in Formula I. Formula I.
[0019] In the application, the mass ratio of the donor and the acceptor is preferably 0-10:10-0, and in specific embodiments of the application, the mass ratio can be 0:10, 1:9, 2:8, 3:7, 4:6, 5:5, 6:4, 7:3, 8:2, 9:1 or 10:0.
[0020] In the application, the preparation method of the compound of the structure shown in Formula I preferably comprises the following steps: The compound of the structure shown in Formula 1, 2-(5,6-dichloro-2,3-dihydro-3-oxo-1H-inden-1-ylidene)malononitrile, pyridine and an organic solvent are mixed to perform a condensation reaction, so as to obtain the compound of the structure shown in Formula I.
[0021] In the application, the molar ratio of the compound of the structure shown in Formula 1 and 2-(5,6-dichloro-2,3-dihydro-3-oxo-1H-inden-1-ylidene)malononitrile is preferably 7:19.
[0022] In the present application, the ratio of the compound of the structure shown in formula 1 to the organic solvent is preferably 7 mol:3 L; the organic solvent preferably includes chloroform.
[0023] In the present application, the volume ratio of the pyridine to the organic solvent is preferably 1:60.
[0024] In the present application, the temperature of the condensation reaction is preferably 55-70℃, and the time is preferably 9-12h; in specific embodiments of the present application, the temperature of the condensation reaction can be 60℃ or 65℃, and the time can be 10h or 11h; the condensation reaction is preferably carried out under a protective atmosphere.
[0025] After the condensation reaction, the present application preferably further comprises: mixing the product obtained by the condensation reaction with methanol for precipitation, and then eluting the obtained precipitate after column chromatography.
[0026] In the present application, the mass of platinum is preferably 5-25% of the mass of the organic photovoltaic heterojunction nanoparticles, and in specific embodiments of the present application, it can be 8%, 10%, 12%, 15%, 18%, 20% or 24%.
[0027] The present application also provides a preparation method of the organic photovoltaic heterojunction nanoparticles of the above technical solution, comprising the following steps: Mixing the organic solution of the donor and / or the organic solution of the acceptor and the aqueous solution of the surfactant to obtain a microemulsion; After removing the organic solvent in the microemulsion, mixing the aqueous solution of chloroplatinic acid to perform photodeposition to obtain the organic photovoltaic heterojunction nanoparticles.
[0028] The present application mixes the organic solution of the donor and / or the organic solution of the acceptor and the aqueous solution of the surfactant to obtain a microemulsion.
[0029] In the present application, the volume ratio of the aqueous solution of the surfactant to the total volume of the organic solution of the donor and the organic solution of the acceptor is preferably 1:1; the concentration of the donor in the organic solution of the donor is preferably 0.5 mg / mL; the concentration of the acceptor in the organic solution of the acceptor is preferably 0.5 mg / mL; the organic solvent in the organic solution of the donor and the organic solution of the acceptor preferably includes chloroform; the concentration of the surfactant in the solution of the surfactant is preferably 0.5wt%, and the surfactant preferably includes sodium dodecyl sulfate.
[0030] In the present application, the emulsification is preferably carried out under the condition of ice bath; the emulsification is preferably carried out under the condition of ultrasonic, and the power of the ultrasonic is preferably 300W and the time is preferably 7min.
[0031] After obtaining the microemulsion, the present invention removes the organic solvent from the microemulsion and mixes it with an aqueous solution of chloroplatinic acid for photodeposition to obtain the organic photovoltaic heterojunction nanoparticles.
[0032] In this invention, the removal method preferably includes rotary evaporation.
[0033] In this invention, the step of removing the solution and mixing it with the aqueous solution of chloroplatinic acid preferably further includes filtering the solution obtained after removal.
[0034] The present invention does not have any special limitations on the filtration, as long as large aggregates are removed and a well-dispersed nanoparticle dispersion is obtained.
[0035] In this invention, the volume ratio of the microemulsion to the chloroplatinic acid solution is preferably 800:1, and the concentration of the chloroplatinic acid solution is preferably 3 mg / mL. -1 .
[0036] In this invention, the light intensity of the photodeposition is 100 mW·cm. -2 The time is 6-8 hours.
[0037] The present invention also provides the application of the organic photovoltaic heterojunction nanoparticles described in the above technical solution or the organic photovoltaic heterojunction nanoparticles prepared by the preparation method described in the above technical solution in the photocatalytic reduction of nitrate to synthesize ammonia.
[0038] In this invention, the photocatalytic reduction of nitrate to ammonia preferably includes the following steps: Organic photovoltaic heterojunction nanoparticles, nitrates, hole sacrificial agents, and water are mixed and then subjected to a photocatalytic reaction.
[0039] In this invention, the mass of the organic photovoltaic heterojunction nanoparticles is preferably 25% of the mass of the nitrate, and the nitrate preferably includes potassium nitrate.
[0040] In this invention, the mass ratio of the hole sacrificial agent to nitrate is preferably 6300:1011, and the hole sacrificial agent preferably includes glycerol.
[0041] In this invention, the concentration of nitrate in the mixture obtained after mixing is preferably 0.1M.
[0042] The photocatalytic reaction is preferably carried out in a protective atmosphere, and the temperature of the photocatalytic reaction is preferably 6°C, and the time is preferably 4 hours.
[0043] The following detailed description, in conjunction with embodiments, illustrates the preparation of the organic photovoltaic heterojunction nanoparticles provided by the present invention and their application in photocatalytic ammonia production. However, these descriptions should not be construed as limiting the scope of protection of the present invention.
[0044] Example 1 The steps for preparing PM6:Y6 organic photovoltaic heterojunction nanoparticles using the microemulsion method are as follows: (1) Dissolve PM6 and Y6 in chloroform respectively, and heat at 45°C for 12 hours to obtain PM6 solution (0.5 mg / mL). -1 ) and Y6 solution (0.5 mg mL) -1 ); The PM6 solution and Y6 solution were mixed in a volume ratio of 4:6 to obtain the precursor solution.
[0045] (2) Add 1 mL of 0.5 wt.% sodium dodecyl sulfate aqueous solution to 1 mL of precursor solution, and then sonicate for 7 min using an ultrasonic processor (FS-100T) to obtain microemulsion.
[0046] (3) Excess chloroform in the microemulsion was removed by rotary evaporation to obtain a stable nanoparticle dispersion. Finally, the dispersion was filtered through 0.45 μm mixed cellulose to remove any large aggregates, yielding an aqueous solution of PM6:Y6 nanoparticles.
[0047] Pt-loaded PM6:Y6 organic photovoltaic heterojunction nanoparticles were prepared using the following steps: H2PtCl6 aqueous solution (3 mg / mL) -1 H₂PtCl₆ was added to an aqueous solution of nanoparticles (H₂PtCl₆ mass was 15% of the mass of PM₆:Y₆ nanoparticles, the volume of the aqueous solution of nanoparticles was 20 mL, and the volume of the chloroplatinic acid solution was 2.5 μL), and the solution was heated under a xenon lamp (AM 1.5 G, 100 mW cm⁻¹). -2 After irradiation for 8 hours, Pt was successfully loaded onto nanoparticles, resulting in Pt-loaded PM6:1Br4Cl nanoparticles.
[0048] Example 2
[0049] 1. Under argon protection, compound 1 (221 mg, 0.07 mmol), 0.19 mmol of 2-(5,6-dichloro-2,3-dihydro-3-oxo-1H-inden-1-yl)malononitrile (49 mg, 0.19 mmol), and 30 mL of dry chloroform were added to a two-necked round-bottom flask, followed by the addition of 0.5 mL of pyridine. The resulting reaction mixture was stirred at 70 °C for 12 h. After cooling to room temperature, the reaction mixture was precipitated in 70 mL of methanol. The precipitate was purified by column chromatography on silica gel using petroleum ether / chloroform (v / v = 4 / 5) as the eluent to give the black compound 1Br4Cl.
[0050] Figure 1The NMR spectra of 1Br4Cl are shown in both 1H and 1C NMR spectra.
[0051] The only difference from Example 1 is that Y6 is replaced with 1Br4Cl.
[0052] Figure 2 High-resolution transmission electron microscopy images of PM6:Y6 nanoparticles, PM6:1Br4Cl nanoparticles, and Pt-loaded PM6:1Br4Cl nanoparticles.
[0053] Depend on Figure 2 It can be seen that the Pt-loaded PM6:1Br4Cl nanoparticles exhibit a blended spherical morphology, and the Pt nanoparticles are relatively uniformly distributed.
[0054] The PM6:Y6 nanoparticle aqueous solutions and PM6:1Br4Cl nanoparticle aqueous solutions prepared in Examples 1 and 2 were used to prepare thin films by spin coating. The UV-Vis absorption spectra of the solutions and thin films are shown in the figure. Figure 3 .
[0055] Figure 3 The UV-Vis absorption spectra of PM6:Y6 nanoparticles and PM6:1Br4Cl nanoparticles prepared in Examples 1-2 are shown.
[0056] Depend on Figure 3 It can be seen that all nanoparticles exhibit significant light absorption capabilities in the visible to near-infrared region.
[0057] Application Example 1 The photocatalytic reaction was carried out in an atmosphere containing 0.1 M KNO3, 5.0 wt% glycerol, and 2.5 μg·mL⁻¹ -1 Pt-loaded PM6:1Br4Cl nanoparticles or 2.5 μg·mL -1 The reaction was carried out in an aqueous solution (20 mL) of Pt-loaded PM6:1Br4Cl nanoparticles. The mixed reaction solution was added to the reactor, which was maintained at 6°C using a cooling water circulator. A simulated solar light source (300 W Xe lamp, AM 1.5G filter, 100 mW·cm⁻¹) was used. -2 The ammonia yield was evaluated, and the results are as follows: Figure 4 As shown.
[0058] Figure 4 These are the results of a photocatalysis experiment.
[0059] Depend on Figure 4 It can be seen that Pt-loaded PM6:1Br4Cl NPs achieved a high concentration of 6.79 mmol g after 4 h of illumination. -1 h -1 ammonia production rate ( Figure 4(a) was significantly superior to Y6-based NPs (1.71 mmol g). -1 h -1 ).
[0060] To further investigate the long-term stability of the catalytic system, a continuous irradiation test was conducted for 40 hours. Figure 4 In (b) and (c) the NH3 concentration increased steadily over time while remaining stable at 6 mmol g. -1 h -1 It exhibits excellent photocatalytic stability.
[0061] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. An organic photovoltaic heterojunction nanoparticle, characterized in that, Includes a carrier and Pt loaded on the carrier; The raw materials for the organic photovoltaic heterojunction nanoparticles include donors and / or acceptors; The donor includes PM6, and the acceptor includes Y6 and / or a compound with the structure shown in Formula I; Equation I.
2. The organic photovoltaic heterojunction nanoparticles according to claim 1, characterized in that, The method for preparing the compound with the structure shown in Formula I includes the following steps: The compound with the structure shown in Formula 1, 2-(5,6-dichloro-2,3-dihydro-3-oxo-1H-inden-1-ylidene)malonitrile, pyridine, and an organic solvent were mixed and subjected to a condensation reaction to obtain the compound with the structure shown in Formula 1.
3. The organic photovoltaic heterojunction nanoparticles according to claim 2, characterized in that, The molar ratio of the compound with the structure shown in Formula 1 to 2-(5,6-dichloro-2,3-dihydro-3-oxo-1H-inden-1-ylidene)malononitrile is 7:
19.
4. The organic photovoltaic heterojunction nanoparticles according to claim 2, characterized in that, The ratio of the compound with the structure shown in Formula 1 to the organic solvent is 7 mol: 3 L; the organic solvent includes chloroform. The volume ratio of pyridine to organic solvent is 1:
60.
5. The organic photovoltaic heterojunction nanoparticles according to claim 2, characterized in that, The condensation reaction is carried out at a temperature of 55-70°C for 9-12 hours.
6. The organic photovoltaic heterojunction nanoparticles according to claim 1, characterized in that, The mass ratio of the donor to the recipient is 0~10:10~0.
7. The organic photovoltaic heterojunction nanoparticles according to claim 1, characterized in that, The mass of the platinum is 5-25% of the mass of the organic photovoltaic heterojunction nanoparticles.
8. The method for preparing organic photovoltaic heterojunction nanoparticles according to any one of claims 1 to 7, characterized in that, Includes the following steps: The organic solution of the donor and / or the organic solution of the recipient, and the aqueous solution of the surfactant are mixed and emulsified to obtain a microemulsion; After removing the organic solvent from the microemulsion, it is mixed with an aqueous solution of chloroplatinic acid and photodeposited to obtain the organic photovoltaic heterojunction nanoparticles.
9. The preparation method according to claim 8, characterized in that, The surfactant includes sodium dodecyl sulfate; The concentration of the surfactant in the solution is 0.5 wt%. The concentration of the donor in the organic solution is 0.5 mg / mL; The concentration of the receptor in the organic solution is 0.5 mg / mL; The volume ratio of the aqueous solution of the surfactant to the total volume of the organic solution of the donor and the organic solution of the acceptor is 1:
1. The light intensity of the photodeposition was 100 mW·cm. -2 The time is 6-8 hours.
10. The application of the organic photovoltaic heterojunction nanoparticles according to any one of claims 1 to 7 or the organic photovoltaic heterojunction nanoparticles prepared by the preparation method according to any one of claims 8 to 9 as a catalyst in the photocatalytic reduction of nitrate to ammonia.