# Correlating Structural Properties with Catalytic Stability in Nanocrystalline La(Sr)CoO3 Thin Films Grown by Pulsed Electron Deposition (PED)

## TL;DR

This paper explores how strontium-doped lanthanum cobaltite thin films, made using a sustainable method, can be used as stable gas sensors for detecting nitrogen dioxide at high temperatures.

## Contribution

The study demonstrates that Sr-doped LaCoO3 films fabricated via PED offer enhanced gas-sensing performance and stability at high temperatures.

## Key findings

- Sr-doping refines the microstructure, resulting in smaller crystallites and a uniform surface.
- La0.8Sr0.2CoO3 shows the highest sensitivity and stability for NO2 sensing up to 350 °C.
- PED proves to be an effective method for producing high-quality, complex oxide thin films.

## Abstract

This study investigates the structural, morphological, and gas-sensing properties of pure and strontium-doped lanthanum cobaltite (La1−xSrxCoO3) perovskite thin films obtained by Pulsed Electron Deposition (PED). This sustainable ablative technique successfully produced high-quality, dense, nanocrystalline films on Si and MgO substrates, demonstrating excellent stoichiometric transfer from the source targets. A comprehensive analysis using XRD, SEM, TEM, AFM, and XPS was conducted to characterize the films. The results show that Sr-doping significantly refines the microstructure, leading to smaller crystallites and a more uniform surface topography. Gas sensing measurements, performed in a temperature range of 100–450 °C, revealed that all films exhibit a characteristic p-type semiconductor response to nitrogen dioxide (NO2). The La0.8Sr0.2CoO3 composition, in particular, demonstrated the most promising performance, with enhanced sensitivity and excellent operational stability at temperatures up to 350 °C. These findings validate that PED is a reliable and precise method for fabricating complex oxide films and confirm that Sr-doped LaCoO3 is a highly promising material for developing high-temperature NO2 gas sensors.