Incorporation of Vanadium(V) Oxide in Hybrid Hole Transport Layer Enables Long-term Operational Stability of Perovskite Solar Cells

Abstract

Recent studies have shown that charge transport interlayers with low gas permeability can increase the operational lifetime of perovskite solar cells serving as a barrier for migration of volatile decomposition products from the photoactive layer. Herein we present a hybrid hole transport layer (HTL) comprised of p-type polytriarylamine (PTAA) polymer and vanadium(V) oxide (VO x ). Devices with PTAA/VO x top HTL reach up to 20% efficiency and demonstrate negligible degradation after 4500 h of light soaking, whereas reference cells using PTAA/MoO x as HTL lose ∼50% of their initial efficiency under the same aging conditions. It was shown that the main origin of the enhanced device stability lies in the higher tolerance of VO x toward MAPbI 3 compared to the MoO x interlayer, which tends to facilitate perovskite decomposition. Our results demonstrate that the application of PTAA/VO x hybrid HTL enables long-term operational stability of perovskite solar cells, thus bringing them closer to commercial applications.

Combination of Metal Oxide and Polytriarylamine: A Design Principle to Improve the Stability of Perovskite Solar Cells

“…According to the literature, such configuration allows achieving high operational stabilities and competitive efficiencies for ZnO-based PSCs [43]. The stability evaluation was performed in the lightsoaking chamber's (Figure 3b) built-in glovebox with an inert atmosphere and control of oxygen and water concentration <0.01 ppm [16]. The unencapsulated devices were exposed to the constant illumination of high-power white light-emitting diodes (70 ± 3 mW/cm 2 ) and a temperature of 45 ± 1 • C for 1250 h, which corresponded to the recommended degradation protocol ISOS-L-2I [44].…”

“…In brief, it was demonstrated that the SiO x thin layer and reduced MO x layers appeared between Si and MO x , leading to Fermi level equilibration across the interface [14]. In addition, such advantages of MO x , with high conductivity and the ability to form a smooth pinholefree layer with organic HTLs, enable high efficiencies in PSCs of more than 20% [15,16]. Additionally, the high transparency of MO x permits their application in inverted PSC configurations [17].…”

“…There are numerous reports on the application of MoO x [20][21][22][23][24][25][26] and VO x [16,22,[27][28][29][30][31] as HTLs in perovskite solar cells. WO x was previously reported as a component of an efficient double-layer ETL [32] and HTLs [8,33,34].…”

Impact of Synthetic Route on Photovoltaic Properties of Isoindigo‐Containing Conjugated Polymers

“…The hole‐collecting electrode consisting of MoO x (10 nm) and Ag (100 nm) was deposited using thermal evaporation, resulting in the final configuration of ITO/SnO 2 /PCBA/CH 3 NH 3 PbI 3 /HTL/MoO x /Ag (Figure 5b). [ 35 ]…”

Recent Progress in the Semiconducting Oxide Overlayer for Halide Perovskite Solar Cells

“…Further, an imperfect interface at the perovskite/SOOM causes high resistance, low transport, and high interfacial recombination ( Figure 8 a); however, research on well‐established methods for depositing SOOMs on top of perovskite is lacking. [ 108–110 ] Although HPSCs with SOOMs are usually expected to be very stable under humid, light, and thermal stress conditions because of their structural stability, the perovskite/SOOM interface might suffer from a certain degradation mechanism that should be suppressed to ensure the stability of HPSCs. [ 76,109 ] For instance, during the thermal degradation of the perovskite/NiO interface, the large negative enthalpy of the NiO reaction with HI arising from MAI causes the formation of NiI 2 (Figure 8a).…”