"When the sun rises, the river is more red than fire. When spring comes, the river is as green as blue. "As we all know, the sun, as the energy source of life on the earth, gives the earth vitality and the power of social development. Nowadays, in the era of electricity and network, how to get energy from sunlight effectively has become an important topic of human civilization progress, so the development of solar cells has also attracted more and more attention. Compared with the traditional silicon-based solar cells, perovskite solar cells have the characteristics of simple manufacturing process, strong absorption capacity and defect resistance. At present, the photoelectric conversion efficiency of single perovskite solar cell has gradually approached the s-q limit, so it has a great application prospect. However, the instability of water and UV light in the air restricts the development of perovskite solar cells. However, the instability is mainly due to the internal defects gathered in the interface and grain boundary, so how to effectively suppress the defects and improve the stability of perovskite has become the most important in the field of perovskite solar cells.
To solve this problem, Professor Yang Yang's research group of UCLA and Professor Zhu Jia's research group of Nanjing University used a new type of polymerization assisted grain growth in the growth of calcium titanium deposits, Pagg) method can effectively reduce the defect density of perovskite and enhance the stability of perovskite solar cells. Relevant papers were published online on advanced materials (DOI: 10.1002 / ADMA. 201907769). The first authors of the paper were Zhao yepin, a doctoral student of UCLA, and Zhu Pengcheng, a doctoral student of Nanjing University. In this scheme, polymer monomers are added into the PbI2 precursor solution. During the formation of PbI2 film, the monomers polymerize and the polymer formed is distributed on the grain boundary. In the following perovskite film formation process, due to the higher binding energy of the polymer and Pb, it is difficult to be replaced by amiodarone, so the polymer will tend to be distributed at the grain boundary. The polymer at the grain boundary can be bound to the partially coordinated PB to eliminate the defect sites. At the same time, due to the higher binding energy of the polymer and Pb, the increase of the reaction barrier and the decrease of the nucleation point significantly increase the size of perovskite grains, thus further reducing the number of perovskite grain boundaries. The structure of polymer chain and perovskite grain is similar to that of reinforced concrete. Under the action of reinforcement (polymer), concrete (perovskite) becomes stronger and more durable. The improved perovskite solar cell achieves 23% of the work efficiency, and can maintain 85.7% of the initial work efficiency after 504 hours of continuous illumination. At the same time, after 2208 hours of room temperature storage, the initial working efficiency of 91.8% can be maintained. The remarkable improvement of the stability of the cell indicates the feasibility of the polymerization assisted growth of perovskite grains, and the variety of polymer types and functions provide a space for further improvement of this method. This study combines the dynamic growth process of organic polymer and inorganic polycrystalline materials, and provides a new idea for improving the stability of perovskite solar cells.
Guess you love it.
AFM: interlayer doping strategy to improve the zinc storage performance of V2O5 cathode materials for zinc ion batteries small methods
MaterialsViewsChina
Official wechat platform
Focus on new information of materials
Material Daniel vs rookie interview
MVC paper ranking list is newly published every month
What are you waiting for? Join us for micro interaction!!!
Microsignals: materialsviews
Microblog: materialsviews China
You are welcome to forward and share. Please contact:
materialsviewschina@wiley.com
Pay attention to the cutting edge of material science, please long press the identification QR code
Click "read original" in the lower left corner to read the original advanced materials