CsPbBr₃ quantum dots assisted crystallization of solution-processed perovskite films with preferential orientation for high performance perovskite solar cells

Abstract

The performance of hybrid perovskite solar cells (PSCs) is significantly influenced by the crystallization and morphology of perovskite films. Herein, a novel method of CsPbBr 3 quantum dots (QDs) assisted nucleation is applied to prepare high quality solution-processed methylammonium lead iodide (MAPbI 3 ) films by employing CsPbBr 3 QDs as an additive into diethyl ether anti-solvent. The appropriate amount of CsPbBr 3 QDs can act as effective heterogeneous nucleation centers, leading to the formation of smooth and pinhole-free perovskite films with increased grain size. Furthermore, the growth direction of MAPbI 3 grains is regulated by CsPbBr 3 QDs, exhibiting preferential orientation of (110) plane. Therefore, the MAPbI 3 films with CsPbBr 3 QDs modification show reduced defects and increased carrier lifetime. As a result, the champion PSC with a maximum power conversion efficiency (PCE) up to 20.17% is achieved and 85% of its initial PCE is maintained after aging 1000 h at room temperature under a relative humidity of 50%. This work demonstrates a feasible way to prepare high quality perovskite films for optoelectronic applications.

Improving the performance of inorganic perovskite solar cells via the perovskite quantum dot dynamically mediated film growth method

“…The decomposition products, which are the components that make up the perovskite film, can enter the perovskite lattice to passivate both Cs + cation and halide ion vacancy defects, which has been demonstrated by previous work. 29,34 Finally, at the annealing stage, a high-quality perovskite film was formed after annealing at 125 1C.…”

Application of Quantum Dot Interface Modification Layer in Perovskite Solar Cells: Progress and Perspectives

“…This enhanced phase stability, ultimately achieving a PCE of 20.82%. In 2020, Yao et al [111] introduced 0.001 mg/mL CsPbBr 3 QDs into PSCs, and the QDs provided non-uniform phase-shaped nucleation centers for MAPbI 3 films, allowing the (110) crystal plane to be denser (Figure 6b). Pinholes on the film surface were effectively eliminated, reducing surface roughness and avoiding carrier capture by defects on the film.…”

“…The PCE of the final champion device was 20.17%. All details are displayed in Table 5 [103][104][105][108][109][110][111][112]. 4.2.3.…”

Perovskite Nanocrystals: Synthesis, Stability, and Optoelectronic Applications

“…In addition to directly serving as the absorber in a photovoltaic device, PNCs are also used as raw materials to fabricate bulk films. [ 160,171–175 ] Kamat et al deposited CsPbBr 3 QDs layer by layer, followed by annealing to cast stable films of desired thickness, which solve the problem of CsPbBr 3 deposition via solution processing due to the poor solubility of CsBr. [ 174 ] In addition, PNCs have been used as the interface modifier to engineer the band alignment.…”