First-principles calculations are used to explore the electronic properties of the interfaces between the Pb-free double perovskite Cs2NaBiI6 and the MXenes Sc2CO2 and Sc2C(OH)2. The effect of the termination group on the stability, ionization potential, electron affinity, and band alignment is investigated. We find a type II band alignment at the Cs2NaBiI6/Sc2CO2 interface, which permits charge transfer, and a type III band alignment at the Cs2NaBiI6/Sc2C(OH)2 interface, which results in electron–hole recombination. Sc2CO2 turns out to be highly promising for solar cell applications due to an almost ideal ionization potential difference to Cs2NaBiI6.
ASJC Scopus subject areas
- Materials Science(all)