# Enduring Luminescence: Water and Heat Stable Perovskite Films via Hierarchical Hydrophobic Encapsulation

## TL;DR

Researchers developed a method to create stable perovskite films that resist water and heat, making them suitable for long-lasting optical devices.

## Contribution

A novel hierarchical hydrophobic encapsulation strategy using PDMS and silica on a carbon skeleton to stabilize perovskite films.

## Key findings

- The films showed a water contact angle exceeding 146.8°, indicating strong hydrophobicity.
- Photoluminescence stability was maintained for 40 days in air and 36 days under water.
- The films remained stable at temperatures up to 100 °C.

## Abstract

Lead halide perovskite
nanocrystals have emerged as highly promising
materials for optical devices due to their high photoluminescence
quantum yield, excellent color purity, and low stimulated emission
thresholds. However, one of the significant challenges limiting their
practical application is the instability of nanocrystal films under
various environmental conditions and elevated temperatures. In this
study, we present a stabilization strategy involving the deposition
of CsPbBr3 nanocrystals onto a template composed of a silica
layer grown on a low-cost, soot-derived carbon skeleton, followed
by hydrophobic encapsulation using polydimethylsiloxane (PDMS). The
resulting thin films exhibited hydrophobic characteristics with a
water contact angle exceeding 146.8°, retained high photoluminescence
stability for up to 40 days in ambient air and 36 days under water,
and demonstrated thermal resistance up to 100 °C. The incorporation
of PDMS created a reliable moisture barrier, greatly boosting the
perovskite layer’s resistance to environmental degradation.
The results demonstrate that our approach offers a viable strategy
for developing long-lasting and environmentally robust coatings for
perovskite-based devices.