# Reducing Nonradiative Recombination Losses in Tin-Based Perovskite LEDs Utilizing a Self-Assembled Monolayer

## TL;DR

Researchers improved the efficiency of tin-based perovskite LEDs by using a self-assembled monolayer to reduce energy losses.

## Contribution

First use of a self-assembled monolayer as a hole-selective layer in tin-based perovskite LEDs.

## Key findings

- Replacing PEDOT:PSS with EADR03 reduced nonradiative recombination losses.
- The new layer improved external quantum efficiency by 3-fold.
- EADR03 acted as both an electron-blocker and hole-injector.

## Abstract

Tin-based perovskites
are emerging as less-toxic alternatives
to
their lead-based counterparts for optoelectronic devices, such as
solar cells and light-emitting diodes (LEDs). However, despite their
great potential, the efficiency of pure red tin-based perovskite LEDs
(Sn-LEDs) still lags behind that of lead-based perovskite LEDs (Pb-LEDs),
partly due to the poor electron blocking at the PEDOT:PSS/perovskite
interface. This leads to detrimental nonradiative recombination pathways
that limit the performance of the LEDs. In this study, we replaced
the conventional PEDOT:PSS layer with the self-assembled monolayer
(SAM) EADR03, presenting, to the best of our knowledge, the first
report of a SAM employed as a hole-selective layer in Sn-LEDs. EADR03
simultaneously acted as an efficient electron-blocking and hole-injecting
layer, thereby reducing interfacial recombination losses and enhancing
the LEDs’ performance. As a result, we achieved a 3-fold enhancement
in external quantum efficiency, propelling the advancement of more
efficient tin-based perovskite LEDs.