"Monolithic multijunction photovoltaics: mapping bandgap and radiative coupling."

Invited seminarWhen: Tuesday, June 11, 2024 - 12:00 to 13:30
Where: Room number TD2003AA Max. of 63 people
Presented by: Dr. Antonio Guerrero

Abstract: 

" Monolithic multijunction photovoltaics relate to series connected arrays of single p-n junction sub-cells that optimize power conversion efficiency (PCE). For outdoor applications, the focus is set on absorbing most of the incident AM1.5G spectrum, for which the bandgap combination of absorber materials must be set and previous estimations of the detailed balance efficiency limit suggest that the higher the number of sub-cells the higher the ultimate PCE. However, as presented in this seminar, care must be taken because not always more junctions lead to better performance. This is of special importance for metal halide perovskites-based tandem and triple junction devices whose high band gap tunability allows a large spam of material combinations. Moreover, regardless of the bandgap combination, the interfaces between sub-cells not only remain a challenge for non-radiative recombination but also trigger the radiative recombination due to bandgap coupling in detailed balance. This seminar presents suggestions for device design that minimize not only general performance losses but also particularly those due to sub-cell-to-sub-cell parasitic radiative recombination."