The stabilization of grain boundaries and surfaces of the perovskite layer is critical to extend the durability of perovskite solar cells. Here we introduced a sulfonium-based molecule, dimethylphenethylsulfonium iodide (DMPESI), for the post-deposition treatment of formamidinium lead iodide perovskite films. The treated films show improved stability upon light soaking and remains in the black alpha phase after two years ageing under ambient condition without encapsulation. The DMPESI-treated perovskite solar cells show less than 1% performance loss after more than 4,500 h at maximum power point tracking, yielding a theoretical T80 of over nine years under continuous 1-sun illumination. The solar cells also display less than 5% power conversion efficiency drops under various ageing conditions, including 100 thermal cycles between 25°C and 85°C and an 1,050-h damp heat test.
Details
Title
Multifunctional sulfonium-based treatment for perovskite solar cells with less than 1% efficiency loss over 4,500-h operational stability tests
Grant
Swiss National Science Foundation European Union's Horizon 2020 research and innovation programme Horizon Europe framework programme for research and innovation Project Ricerca@CNR PHOTOCAT Italian Ministry of Environment and Energy Security European Union's Horizon Europe research and innovation programme German Federal Environmental Foundation (DBU) Engineering and Physical Sciences Research Council (EPSRC) Doctoral Prize Fellowship: 200020_185041 Winton Sustainability Fund Studentship: 200021_213073 Oppenheimer Research Fellowship: 764047 Schmidt Science Fellowship: 101084124-DIAMOND Research Fellowship at Murray Edwards College: CUP B93C21000060006 Royal Society and Tata Group: CSEAA_00011 EPSRC European Research Council Biotechnology and Biological Sciences Research Council (BBSRC) University of Warwick Uppsala University UF150033 EP/R023980/1 756962 EP/T015063/1 EP/R029946/1