Journal
ADVANCED FUNCTIONAL MATERIALS
Volume 32, Issue 38, Pages -Publisher
WILEY-V C H VERLAG GMBH
DOI: 10.1002/adfm.202205009
Keywords
alkyldiammonium ligands; defect passivation; perovskite solar cells; stability
Categories
Funding
- National Key Research and Development Project funding from the Ministry of Science and Technology of China [2021YFB3800104]
- National Natural Science Foundation of China [51822203, 51861145404, 52002140, U20A20252, 62105293]
- Young Elite Scientists Sponsorship Program by CAST
- Natural Science Foundation of Hubei Province [ZRMS2020001132]
- Self-determined and Innovative Research Funds of HUST [2020kfyXJJS008]
- Shenzhen Science and Technology Innovation Committee [JCYJ20180507182257563]
- Innovation Project of Optics Valley Laboratory [OVL2021BG008]
Ask authors/readers for more resources
This study systematically investigates the defect passivation role of several alkylammonium salts in formamidinium-cesium perovskite, finding that BDAI(2) salt exhibits the best passivation effect by reducing trap-state density and enhancing carrier extraction. BDAI(2)-modified devices achieve impressive efficiencies in both rigid and flexible substrates, with 92% of the initial efficiency maintained after long-term operation under continuous illumination. The mechanical flexibility of the BDAI(2)-modified flexible device is also improved due to the release of residual stress.
Organic ammonium salts have been widely used for defect passivation to suppress nonradiative charge recombination in perovskite solar cells (PSCs). However, they are prone to form undesirable in-plane favored 2D perovskites with poor charge transport capability that hamper device performance. Herein, the defects passivation role of alkyldiammonium including 1.6-hexamethylenediamine dihydriodide (HDAI(2)), 1,3-propanediamine dihydriodide (PDAI(2)), and 1.4-butanediamine dihydriodide (BDAI(2)) for formamidinium-cesium perovskite is systematically investigated. With help of density functional theory (DFT) calculations, BDA with suitable size can synergistically passivate two defect sites on perovskite surfaces, showing the best defect passivation effect among the above three alkyldiammonium salts. Perovskite films based on BDAI(2) modification are found to keep the 3D perovskite phase with considerably reduced trap-state density, and enhanced carrier extraction. As a result, the BDAI(2)-modified devices deliver impressive efficiencies of 23.1% and 20.9% for inverted PSCs on the rigid and flexible substrates, respectively. Moreover, the corresponding encapsulated rigid devices maintain 92% of the initial efficiency after operating under continuous 1-sun illumination with the maximum power point tracking for 1000 h. Furthermore, the mechanical flexibility of the BDAI(2)-modified flexible device is also improved due to the release of residual stress.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available