Highly Sensitive NH₃ Sensors Using CVD and Epitaxial Graphene Functionalised with Vanadium(V) Oxide: A Comparative Study

• Main Authors: Margus Kodu, Artjom Berholts, Tauno Kahro, Jens Eriksson, Rositsa Yakimova, Tea Avarmaa, Indrek Renge, Harry Alles, Raivo Jaaniso
• Format: Article
• Language: English
• Published: MDPI AG 2018-11-01
• Series: Proceedings
• Subjects: ammonia; CVD graphene; epitaxial graphene on SiC; gas sensor; pulsed laser deposition; selectivity; single layer graphene; UV light activation; vanadium(V) oxide
• Online Access: https://www.mdpi.com/2504-3900/2/13/854
• ISSN: 2504-3900

Exceptionally sensitive and selective graphene-based chemiresistive gas sensors were produced as a result of graphene functionalisation with a sub-nanometer V₂O₅ layer by using the method of pulsed laser deposition. Two different types of graphene were used—epitaxial graphene on SiC and CVD graphene on Si/SiO₂—and both showed remarkable enhancement of sensing properties in terms of response and recovery speed, response magnitude and selectiveness towards NH₃ gas. The epitaxial graphene-based sensor was demonstrating the highest relative response towards ammonia amounting to 80% for 0.1 ppm NH₃.