Foundry staff and users discovered that bromide inclusions within complex halide perovskites alter the formation dynamics and defect physics of wide bandgap (WBG) halide perovskites.
Significance and Impact
This discovery offers a model of the formation dynamics of WBG halide perovskites and provides a fundamental understanding of the importance of precursor engineering and crystallization control to developing more efficient and stable photovoltaics based on WBG halide perovskites.
- The researchers specifically focused on the triple cation mixed-halide WBG perovskite FAMACsPb(I0.8Br0.2)3. They applied in situ photoluminescence monitoring to complex halide perovskites to unveil that bromide inclusions alter the formation dynamics and defect physics of WBG halide perovskites.
- Since bromide and iodide have different solubility with the coordinating solvents used for perovskite deposition, the team used density functional theory to calculate the interaction energies of PbXX’ with DMSO.
- They found that intrinsic defects formed readily during the halide homogenization process, and so the final film had a higher defect density across the entire film depth. Consequently, the WBG composition suffered from more severe nonradiative recombination losses and thus inferior optoelectronic properties and device performance.