1. Introduction
Solar energy has emerged as a crucial renewable energy source in the pursuit of sustainable development. Solar panels play a central role in converting solar energy into electricity. However, the efficiency of photovoltaic conversion in solar panels has been a subject of extensive research due to various limitations. This article focuses on a study related to the preparation of new batteries for high-efficiency conversion of solar panels and an intelligent acquisition system.
1.1 Background of Solar Panels
Solar panels, also known as photovoltaic (PV) panels, are devices that convert sunlight into electricity. The basic principle involves the photovoltaic effect, where photons from sunlight excite electrons in a semiconductor material, creating an electric current. The efficiency of this conversion process is of utmost importance as it determines the amount of electricity that can be generated from a given area of solar panels.
1.2 Importance of High-Efficiency Conversion
High-efficiency conversion in solar panels is essential for several reasons. Firstly, it allows for more electricity to be generated from a limited area, making solar power more viable in areas with limited space. Secondly, it improves the economic viability of solar energy projects by reducing the cost per unit of electricity generated. Thirdly, it contributes to a more sustainable energy future by maximizing the utilization of solar energy resources.
1.3 Overview of the Study
This study aims to develop a new type of solar panel battery with high power conversion efficiency and an intelligent acquisition system. The research involves the preparation of a broadband-gap material using 1,3 – dibromo – 5,5 – dimethylhydantoin (DBH) and diketone isoindole as donor materials and non – fullerene Y6 – BO and PTIC as receptor materials. The properties of the prepared materials and batteries are then tested and analyzed to determine their suitability for use in solar panels.
2. Materials and Methods
2.1 Materials Used
- Chemicals: A wide range of chemicals were used in this study, including n – hexane, dichloromethane, trichloromethane, toluene, ether, N,N – dimethylformamide, trimethyltin chloride, n – butyl lithium, tetrahydrofuran, tetrakis(triphenylphosphine)palladium, 1,3 – dibromo – 5,5 – dimethylhydantoin.
- Receptor Materials: Non – fullerene Y6 – BO and PTIC were used as receptor materials.
The following table summarizes the materials used:
| Material Type | Materials |
|---|---|
| Chemicals | n – hexane, dichloromethane, trichloromethane, toluene, ether, N,N – dimethylformamide, trimethyltin chloride, n – butyl lithium, tetrahydrofuran, tetrakis(triphenylphosphine)palladium, 1,3 – dibromo – 5,5 – dimethylhydantoin |
| Receptor Materials | Y6 – BO, PTIC |
2.2 Equipment Employed
The experimental equipment included a Shimadzu UV – 1800 ultraviolet – visible absorption spectrometer, a D – 120 step profiler, a CHI620D cyclic voltammetry analyzer, Schlenk tubes, flasks, and an evaporation coating instrument.
2.3 Preparation of Donor Material
The donor material was prepared through a series of complex chemical reactions. The steps involved adding various chemicals to Schlenk tubes and flasks, followed by reactions at specific temperatures and times. The reactions included evaporation, filtration, and extraction processes to obtain the final product A6. The detailed steps are as follows:
- First Step: Add 2.313 g of mono – fluoro – mono – alkoxy, 8.988 g of tributyl(3 – thiophenyl)tin, 0.4973 g of tetrakis(triphenylphosphine)palladium, and 45 mL of anhydrous dichloromethane (DMF) to a Schlenk tube and let it stand at 130 °C for 12 h before evaporation treatment. The remaining substance was then processed with dichloromethane to obtain product A1.
- Second Step: Add 1 g of A1, 4.713 g of anhydrous ferric chloride, and 200 mL of anhydrous DCM to a flask and react at 26 °C for 5 h. Then add silica powder. After 3 min, take the filtrate and evaporate it. The obtained substance was then processed with n – hexane to obtain product A2.
- Third Step: Pour 23 mL of trichloromethane into a flask, add 230 mg of A2, 320 ng of NBS, and 0.7 mL of concentrated sulfuric acid while stirring. React at 26 °C for 30 min. Then add 76 mg of N – bromo – succinimide (NBS) and 0.2 mL of concentrated sulfuric acid again. After 30 min, pour a mixture of 20 mL of methanol and 1 mL of water into it and filter to obtain product A3.
- Fourth Step: Add 300 mg of A3, 944 mg of tributyl(4 – (2 – butyl – octyl)thiophene – 2 – yl)tinane, 82 mg of tetrakis(triphenylphosphine)palladium, 10 mL of toluene, and 2 mL of DMF to a Schlenk tube and react at 112 °C for 12 h. When the reactant cools to 26 °C, add water and PE solution for extraction. Then, after evaporation, use a polyethylene (PE) to DCM solution with a volume ratio of 1:2 for separation to obtain product A4.
- Fifth Step: Pour 25 mL of trichloromethane into a flask, add 220 mg of A4, and 106.2 mg of NBS. After 2 h, add 25 mL of methanol, filter the solution, and add a 1:2 mixture of PE and DCM to obtain product A5.
- Sixth Step: Add 80 mg of A5, 80.7 mg of 2 – ethyl – hexyl – oxybenzene – [1,2 – b:4,5 – b’]dithiophene (FBDT – Sn), 2.37 mg of tris(dibenzylideneacetone)dipalladium, and 7.84 mg of tris(orthomethyl)phenylphosphorus, and 0.8 mL of anhydrous toluene to a Schlenk tube and react at 112 °C for 16 h. Then add 8 mL of chlorobenzene and stir for 10 min. Then pour 100 mL of methanol into the mixture and filter to obtain the DCM component, as well as the DCM and carbon – fluorine compound (CF) component and the trichloromethane component with a volume ratio of 1:1.5. Pour the trichloromethane component into 100 mL of methanol, filter and dry to obtain product A6.
2.4 Preparation of Solar Panel Batteries
- Base Cleaning: A 1.5 cm × 1.5 cm indium tin oxide glass was used as the base of the solar panel battery. The base was first cleaned in deionized water, acetone, and isopropyl alcohol using an ultrasonic cleaner for 15 min each. Then it was placed in an ozone – ultraviolet cleaning device for another 15 min to remove surface contaminants.
- Spin – Coating Film: PEDOT/PSS was spin – coated onto the base at a speed of 4000 r/min and annealed at 150 °C for 15 min to obtain a PEDOT/PSS film. Then, A6 was mixed with the super – narrow – bandgap receptor Y6 – BO and the narrow – bandgap receptor PTIC in a set ratio and stirred in a nitrogen environment for 12 h. The well – stirred mixture was then spin – coated onto the PEDOT/PSS film and annealed at 150 °C for 15 min. Finally, PDIN was dissolved in a 2 mg/mL MeOH/AcOH (1000:3) solution and spin – coated at a speed of 5000 r/min. The film was then dried in natural conditions to complete the spin – coating process.
- Evaporation – Deposited Electrodes: Under a pressure less than Pa, silver was evaporated onto the spin – coated base at a speed of to complete the preparation of the solar panel battery.
3. Results and Analysis
3.1 Characterization of Synthesized Materials
- Absorption Spectrum
The absorption spectra of the prepared A6 material in solution and film states were analyzed using an ultraviolet – visible absorption spectrometer. The results showed that the A6 material reached its maximum ultraviolet – visible absorption intensity at 532 nm in the solution state and 568 nm in the film state, with only one maximum value, indicating strong aggregation. The optical bandgap of A6 was calculated to be 2.10 eV, classifying it as a broadband – gap material. - Electrochemical Properties
The cyclic voltammetry analyzer was used to test A6. The oxidation potential and reduction potential of A6 were found to be 0.7 V and – 1.98 V, respectively. Based on these values, the orbital energy level and the lowest unoccupied orbital energy level of A6 were calculated to be – 5.5 eV and – 2.8 eV, respectively. The electrochemical bandgap and the effective lowest unoccupied orbital energy level of A6 were calculated to be 2.69 eV and – 3.46 eV, respectively. It was observed that the introduction of diketone isoindole could reduce the orbital energy level of the material.
3.2 Performance of Solar Panel Batteries
- Optimal Ratio Determination
To obtain the solar panel battery with the highest efficiency, different mass ratios of donor and receptor materials and film thicknesses were tested. The results are shown in the following table:
| Material | Index | Ratio | Energy Conversion Efficiency (%) |
|–|–|–|–|
| A6:Y6 – BO | Donor – receptor mass ratio | 1:1 | 11.22 |
| | | 1:1.5 | 15.23 |
| | | 1:2 | 13.66 |
| | Film thickness | 80nm | 13.87 |
| | | 100nm | 15.23 |
| | | 120nm | 13.39 |
| A6:PTIC | Donor – receptor mass ratio | 1:1 | 9.38 |
| | | 1:1.5 | 8.45 |
| | Film thickness | 1:2 | 11.37 |
| | | 80nm | 7.22 |
| | | 100nm | 11.37 |
| | | 120nm | 9.22 |
| Material | Index | Ratio | Energy Conversion Efficiency (%) |
| A6:Y6 – BO | Donor – receptor mass ratio | 1:1 | 11.22 |
| 1:1.5 | 15.23 | ||
| 1:2 | 13.66 | ||
| Film thickness | 80nm | 13.87 | |
| 100nm | 15.23 | ||
| 120nm | 13.39 | ||
| A6:PTIC | Donor – receptor mass ratio | 1:1 | 9.38 |
| 1:1.5 | 8.45 | ||
| Film thickness | 1:2 | 11.37 | |
| 80nm | 7.22 | ||
| 100nm | 11.37 | ||
| 120nm | 9.22 |
It was found that when using A6 and Y6 – BO to prepare solar panel batteries, the optimal energy conversion efficiency was 15.23% when the mass ratio of donor and receptor materials was 1:1.5 and the film thickness was 100 nm.
2. Volt – Ampere Characteristics
The volt – ampere characteristic curves of the solar panel batteries prepared under the optimal ratio conditions were analyzed. The results showed that the solar panel batteries prepared with A6 and Y6 – BO materials had a higher power conversion efficiency than those prepared with A6 and PTIC materials, with an overall increase of . This was attributed to the wider light absorption range of the receptor material Y6 – BO.
3. Carrier Transport Properties
The mobility of the solar panel batteries was calculated using the formula . The carrier mobilities of the pure film and the mixed films are shown in the following table:
| Material | Carrier Mobility | Charge Transfer Rate |
|---|---|---|
| A6 | 5.58 ✖ 10^-4 | |
| A6:Y6 – BO(1:1.2) | 2.40 ✖ 10^-4 | 1.04 ✖ 10^-4 |
| A6:PTIC(1:1.2) | 1.83 ✖ 10^-4 | 0.84 ✖10^-4 |
It was observed that the A6/Y6 – BO mixed film had higher carrier mobility and charge transfer ability than the A6/PTIC mixed film.
4. Exciton Dissociation and Bimolecular Recombination
The exciton dissociation results of the new solar panel batteries prepared under A6/PTIC and A6/Y6 – BO conditions and the analysis results of short – circuit current bimolecular recombination under different light intensities were studied. The results showed that when the effective voltage was about 3 V, the short – circuit currents of the solar panel batteries prepared under both conditions reached saturation, and the exciton dissociation efficiencies were 96.22% and 92.38% for A6/Y6 – BO and A6/PTIC, respectively, indicating that A6/Y6 – BO had better charge generation efficiency. The power – law index values of the solar panel batteries prepared with A6/PTIC and A6/Y6 – BO were 0.9750 and 0.9432, respectively, indicating that A6/Y6 – BO had less charge recombination. Overall, the solar panel batteries prepared with A6/Y6 – BO had higher charge generation efficiency and a better recombination ratio.
4. Discussion
4.1 Significance of the Results
The results of this study have several significant implications. Firstly, the successful preparation of the broadband – gap material A6 and its characterization provide a solid foundation for the development of high – efficiency solar panel batteries. Secondly, the determination of the optimal ratio and the analysis of the performance of the solar panel batteries offer valuable guidelines for improving the efficiency of solar panels. Thirdly, the better performance of the A6/Y6 – BO combination in terms of carrier transport, exciton dissociation, and bimolecular recombination highlights its potential for enhancing the overall performance of solar panel batteries.
4.2 Comparison with Previous Studies
Previous studies have also focused on improving the efficiency of solar panel batteries. For example, some studies have explored the use of different semiconductor materials or doping techniques. However, this study differs in its approach by using a specific combination of donor and receptor materials and a detailed optimization process. The results obtained in this study show that the A6/Y6 – BO combination offers a significant improvement in efficiency compared to some of the previously reported methods.