Semiconductor self-assembled monolayers as selective contacts for efficient PiN perovskite solar cells

Abstract

Herein, we studied the use of two different Self Assembled Monolayers (SAMs) made of semiconductor hole transport organic molecules to replace the most common p-type contact, PEDOT:PSS, in PiN methyl ammonium lead iodide perovskite solar cells (PSCs).

Self‐Assembled Ionic Liquid for Highly Efficient Electron Transport Layer‐Free Perovskite Solar Cells

“…The C 1s peaks for BIPH‐II on FTO at 284.4, 285.6, and 288.0 eV are attributed to C−C, C−N, and C−O, respectively. The peaks assigned to ester bonding (C−O) at 288.0 eV (FTO/BIPH‐II) indicate the formation of strong covalent bonds between the ionic liquid and the surface of the FTO substrate …”

Interface limited hole extraction from methylammonium lead iodide films

“…The simplicity of fabrication, low processing temperature and compatibility with roll-to-roll manufacturing processes make this an attractive solar cell architecture but it suffers problems with efficiency and stability, partly due to its acidity, temperature sensitivity and hygroscopic properties. 10 A low processing temperature and stable hole transporting layer based on NiO nanoparticles has been proposed as a superior HEL recently by Jagadamma et al 11 but it is still unclear what the underlying reasons for improved charge extraction from the solar cell are and what role charge transport and interfacial transfer rate play in charge extraction, making it very difficult to compare between different charge extracting materials even for the same perovskite composition and preparation method. This information is crucial when aiming to develop solar cells with hot carrier extraction which potentially can break the Shockley-Queisser limit.…”

Conformal monolayer contacts with lossless interfaces for perovskite single junction and monolithic tandem solar cells

“…40,41 After first occurrences in PSCs as electrode modifications, 42,43 the first hole-selective SAMs were introduced in 2018. 44,45 These molecules covalently bind to the transparent conductive oxide (TCO), e.g., indium tin oxide (ITO), on which the perovskite absorber crystallizes. Due to their hole-selectivity, the SAMs can replace the classical hole-transporting layer.…”