Modification of the fluorinated tin oxide/electron-transporting material interface by a strong reductant and its effect on perovskite solar cell efficiency

Abstract

An organometallic reductant affords ohmic contact between FTO and a perylene electron-transport material.

Elucidating the Role of a Tetrafluoroborate‐Based Ionic Liquid at the n‐Type Oxide/Perovskite Interface

“…From their inception in 2009, photovoltaic devices based on halide perovskites have undergone rapid increases in power have been reported in the literature, such as the introduction of a work function (WF) modifier for example, [31] and through deliberate and thoughtful selection of the chargetransport layers, with the expressed goal of minimizing interfacial recom bination. Additionally, these methods often lead to improved device stability.…”

“…Improving interfaces in perovskite solar cells can be achieved by chemical passivation of the perovskite surface or through tailoring the charge‐selective layers to facilitate better forward carrier transfer . The latter can be readily overcome by adopting various approaches that have been reported in the literature, such as the introduction of a work function (WF) modifier for example, and through deliberate and thoughtful selection of the charge‐transport layers, with the expressed goal of minimizing interfacial recombination. Additionally, these methods often lead to improved device stability …”

Ruthenium pentamethylcyclopentadienyl mesitylene dimer: a sublimable n-dopant and electron buffer layer for efficient n–i–p perovskite solar cells

“…This is somewhat different to what was previously observed for (RhCp*Cp) 2 /C 60 , where devices with a nominal interlayer thickness of 10 nm resulted in large V oc and FF. 42 We believe that the differences may originate from different diffusivity of the two organometallic dopants into the C 60 , as well as from the lower work function of FTO used in the previous work, which would favor electron extraction. In Fig.…”

“…[38][39][40][41] Of most relevance to the present work, a thin layer of one such organometallic dimer pentamethylrhodocene dimer, (RhCp*Cp) 2has been vacuum deposited between FTO and vacuum-deposited ETMs, pinning the Fermi level to the lowest unoccupied molecular orbital (LUMO) of the C 60 . 42 In this work, we have investigated the use of a similar organometallic compoundpentamethylcyclopentadienyl mesitylene ruthenium dimer, 43 (RuCp*mes) 2to dope C 60 in fully vacuum deposited n-i-p perovskite solar cells. (RuCp*mes) 2 has been shown to passivate traps in C 60 at low concentration and to change the semiconductor work function and highest occupied molecular orbital (HOMO) position with respect to the Fermi level upon doping.…”

The Path to Perovskite on Silicon PV

“…We have used metal oxides, organic semiconductors, and they seem to make very good electronic contact to the perovskite. [51][52][53] However, tuning the properties of those materials, for instance doping of the contact materials, has all been part of getting the efficiency up and going up this ladder towards the Shockley-Queisser limit. 54…”