Perovskite Solar Cell Bismuth Modifier Layer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Perovskite thin film solar cells face difficulties in improving photoelectric conversion efficiency due to interfacial defects.
Innovation Solution
A perovskite thin film solar cell structure is enhanced by incorporating a modifier layer made from a bismuth salt solution between the electron transport layer and the perovskite light-absorbing layer, which promotes flatness and large-grain crystallization, reducing interfacial defects and improving efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a perovskite thin film is prepared with simple preparation and good crystallization, then the preparation process is easy and crystallization quality is good, but interfacial defects still exist which negatively impact photoelectric conversion efficiency
Solution Approach 1:
A modifier layer made from bismuth salt solution is introduced between the electron transport layer and the perovskite light-absorbing layer. This intermediary layer serves as a mediator that modifies the electron transport layer surface, reducing interfacial defects and improving the quality of the perovskite thin film without complicating the overall preparation process significantly.
Solution Approach 2:
The electron transport layer undergoes preliminary modification by coating it with the bismuth salt solution before depositing the perovskite light-absorbing layer. This preliminary action prepares the surface in advance to reduce interfacial defects and provide a better substrate for perovskite crystallization, thereby improving photoelectric conversion efficiency.
2Reliability
If a modifier layer made from bismuth salt solution is coated between the electron transport layer and the perovskite light-absorbing layer, then photoelectric conversion efficiency is improved by 19% or higher, but the device structure becomes more complex
Solution Approach 1:
The bismuth salt modifier layer is applied locally at the critical interface between the electron transport layer and the perovskite light-absorbing layer, where interfacial defects have the greatest impact on performance. This localized modification approach improves photoelectric conversion efficiency without requiring complex changes to the entire device structure.
Solution Approach 2:
The concentration of the bismuth salt solution is optimized at 0.1-0.5 mg/mL, and the annealing temperature is set at 100-150°C for 5-10 minutes. By optimizing these parameters, the modifier layer achieves maximum effectiveness in reducing interfacial defects while minimizing the complexity and processing time associated with the additional layer.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The introduction of the bismuth salt modifier layer results in a 19% or higher improvement in photoelectric conversion efficiency compared to unmodified cells, achieving a uniform and flat large-grain perovskite thin film.
Implementation Method 1
the perovskite light-absorbing layer is enabled to have a sufficient crystallization space, thereby obtaining a uniform and flat large-grain perovskite thin film
Implementation Method 2
spin-coating a bismuth salt solution on an electron transport layer and performing annealing to obtain a modifier layer
Implementation Method 3
more trapping sites are also generated, and the perovskite light-absorbing layer is enabled to have a sufficient crystallization space
Implementation Method 4
A perovskite material, which is used as a solar cell light-absorbing material, has not only high efficiency in light absorption and carrier mobility
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Provided in the present invention are a perovskite thin film solar cell and a preparation method therefor. The perovskite thin film solar cell includes an electron transport layer and a perovskite light-absorbing layer which are sequentially arranged on a bottom electrode, wherein a modifier layer is coated between the electron transport layer and the perovskite light-absorbing layer, and a raw material of the modifier layer is a bismuth salt solution. The preparation method for the perovskite thin film solar cell includes: before arranging a perovskite light-absorbing layer, spin-coating a bismuth salt solution on an electron transport layer and performing annealing to obtain a modifier layer, and then arranging the perovskite light-absorbing layer on the modifier layer. According to the perovskite thin film solar cell in the present invention, the problem of more interfacial defects in the perovskite thin film solar cell is remedied by using a modifier, such that the photoelectric conversion efficiency of a device is significantly improved.