Efficient wide band gap hybrid perovskites for monolithic tandem solar cells
Benedikt Dänekamp a, Michele Sessolo a, Lidón Gil-Escrig a, Cristina Momblona a, Daniel Pérez-del-Rey a, Dávid Forgács a, Jorge Ávila a, Henk Bolink a
Proceedings of Perovskite Thin Film Photovoltaics (ABXPV17)
València, Spain, 2017 March 1st - 2nd
Organizers: Henk Bolink and David Cahen
Oral, Jorge Ávila, presentation 044
Publication date: 18th December 2016

Metal halide perovskites have emerged as promising photovoltaic materials, with record efficiencies beyond 20%. Among other, one of the unique properties of perovskites is their tunable band gap. While most studies have been directed towards the developments of small bandgap absorber, wide bandgap systems have not been explored in details. Realizing efficient solar cells with bandgap of about 2 eV would enable the fabrication of perovskite-perovskite tandem cells with efficiencies exceeding 23%, hence surpassing the efficiency of single junction devices. In this work we combine the beneficial stabilizing effects of Cs and FA cations to study the band gap variation and the properties of the perovskite compound Cs0.15FA0.85Pb(BrxI1-x)3 as a function of the halides composition, with the aim of developing an efficient complementary absorber for MAPbI3 in a perovskite tandem device. We have found the perovskite stoichiometry Cs0.15FA0.85Pb(Br0.7I0.3)3 to be a promising candidate, thanks to its band gap of approximately 2 eV. We also present an efficient monolithic tandem solar cells based on Cs0.15FA0.85Pb(BrxI1-x)3 and MAPbI3. By employing doped organic semiconductors, an efficient extraction of the photogenerated charge carriers is ensured, while carrier recombination at the perovskite interfaces is prohibited by using intrinsic and selective charge transport layers. Despite the non-ideal combination of bandgaps in the two subcells, we demonstrate perovskite-perovskite tandem cells delivering an average PCE of 15%, with a maximum efficiency obtained of 18%.

We use our own and third party cookies for analysing and measuring usage of our website to improve our services. If you continue browsing, we consider accepting its use. You can check our Cookies Policy in which you will also find how to configure your web browser for the use of cookies. More info