Atomic Layer Deposition Enabled Perovskite/PEDOT Solar Cells in a Regular n–i–p Architectural Design

Abstract

Perovskite solar cells employing poly(3,4‐ethylenedioxythiophene) (PEDOT) as hole transport layer on top of methylammonium lead halide are reported, yielding a power conversion efficiency of 11% and a 6% stabilized power output. An atomic layer deposition assisted interface architectural approach is adopted to fabricate the n–i–p perovskite/PEDOT devices. The results present a promising next step toward efficient low‐cost perovskite‐based photovoltaic technology.

Electrodeposition of Hole-Transport Layer on Methylammonium Lead Iodide Film: A Strategy To Assemble Perovskite Solar Cells

“…These values fall in the range of the HTM thicknesses (40–300 nm) employed in the case of MAPbI 3 PSCs using PEDOT. 21,22 Raman-spectroscopic studies (Figure 2D) further confirmed the characteristics of an electrochemically deposited PEDOT on top of the MAPbI 3 layer.…”

“…Although it was demonstrated that PEDOT accepts holes as effectively as spiro-OMeTAD, 20 its use apart from a few examples, 21−23 has been restricted to inverted SC designs ( p–i–n junction). The direct spin-coating of the aqueous PEDOT:PSS solution is not a good option because it is known to degrade the perovskite layer.…”

Characterization of optically active perovskite electrodes

“…These values fall in the range of the HTM thicknesses employed in the case of MAPbI3 solar cells using PEDOT. [194,195] Raman-spectroscopic studies ( Figure 53D) further confirmed the presence of a PEDOT layer on the surface of the PSCs.…”

“…Although it was demonstrated that PEDOT accepts holes as effectively as spiro-MeOTAD, [193] its use (apart from a few examples [194][195][196] ) has been restricted to inverted solar cell designs (p-i-n junction). This limit is rooted in the fact that the direct spin-coating of the PEDOT:PSS aqueous solutions would immediately destroy the perovskite layer.…”

“…Such PEDOT layers were subjected to either oxidation at +0.6 V or reduction at −0.6 V for t = 60 s ( Figure 57A and Figure 57B). the performance of PSCs [194] . This reductive post-treatment method, however, had an unintended side-effect, as revealed by cross sectional SEM images (Figure 59A-B).…”