The effect of sodium doping in NiO as a contact layer for perovskite solar cells is investigated. A combined X-ray diffraction and X-ray photoelectron spectroscopy analysis reveals that Na+ mostly segregates as NaOx/NaCl species around NiO crystallites, with the effect of reducing interface capacitance as revealed by impedance spectroscopy. Inspired by this finding, the NiO/perovskite interface in perovskite solar cells is modified via insertion of an ultrathin NaCl interlayer, which increases the NiO work-function by 0.3 eV. This leads to an increase of power conversion efficiency, approaching 18%, and open-circuit voltage due to a remarkable suppression of surface recombination, as revealed by photoluminescence analysis and light intensity–dependent electrical measurements.
From Bulk to Surface: Sodium Treatment Reduces Recombination at the Nickel Oxide/Perovskite Interface / Di Girolamo, D.; Phung, N.; Jost, M.; Al-Ashouri, A.; Chistiakova, G.; Li, J.; Marquez, J. A.; Unold, T.; Korte, L.; Albrecht, S.; Di Carlo, A.; Dini, D.; Abate, A.. - In: ADVANCED MATERIALS INTERFACES. - ISSN 2196-7350. - 6:17(2019), p. 1900789. [10.1002/admi.201900789]
From Bulk to Surface: Sodium Treatment Reduces Recombination at the Nickel Oxide/Perovskite Interface
Di Carlo A.;Abate A.
2019
Abstract
The effect of sodium doping in NiO as a contact layer for perovskite solar cells is investigated. A combined X-ray diffraction and X-ray photoelectron spectroscopy analysis reveals that Na+ mostly segregates as NaOx/NaCl species around NiO crystallites, with the effect of reducing interface capacitance as revealed by impedance spectroscopy. Inspired by this finding, the NiO/perovskite interface in perovskite solar cells is modified via insertion of an ultrathin NaCl interlayer, which increases the NiO work-function by 0.3 eV. This leads to an increase of power conversion efficiency, approaching 18%, and open-circuit voltage due to a remarkable suppression of surface recombination, as revealed by photoluminescence analysis and light intensity–dependent electrical measurements.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
