Properties of chemo-electrical hydrogen sensors based on NiO:Li/Pd thin-films
I.
Sta
*1
, M. Jlassi
1
, M. Kandyla
3
, M. Hajji
1,2
, M. Kompitsas
3
, and H. Ezzaouia
1
.
1
Laboratoire de Semi-conducteurs, Nano-structure et Technologie Avancée, Centre de Recherche et
des Technologies de l’Energie, Technopole de Borj-Cédria, BP 95, 2050 Hammam-Lif, Tunisia
2
Ecole Nationale d’Electronique et des Communications de Sfax, Technopôle de Sfax, Route de Tunis
Km 10, Cité El Ons, B.P. 1163,
3021
Sfax, Tunisia
3
National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, 48, Vasileos
Konstantinou Ave., 11635 Athens, Greece
*
Email of corresponding author:
This work describes the growth and characterization of lithium doped (NiO:Li) thin films for
hydrogen detection. Initially, the NiO:Li thin films with a thickness of 600 nm were grown by
spin-coating on glass substrates. Subsequently, Pd nanoparticles as catalysts were deposited
on the surface by Pulsed laser deposition (PLD). Atomic force microscopy (AFM), scanning
electron microscopy (SEM) and X-ray spectroscopy revealed the surface morphology and
structure and have shown that the NiO:Li/Pd sensing layer has a rougher surface due to the
presence of the Pd nanoparticles.
The thin films were exposed to different hydrogen concentrations in air, under static
conditions, and at various operating temperatures. The results have shown a 10 times higher
sensitivity and faster response and recovery times than pure NiO sensors. Partially covering
the film surface with Pd nanoparticles has demonstrated a significant enhancement of the
sensor response towards hydrogen.
Keywords
: Nickel oxide, lithium doping, Pd nanoparticles, sol-gel, thin films, pulsed laser
deposition, hydrogen gas sensor.
PS2 35
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