Graphene gas sensor for measuring the concentration of carbon dioxide in gas environments
A gas sensor for measuring a concentration of carbon dioxide in a gas environment (GE) is provided. The gas sensor includes a graphene layer having a side facing towards the gas environment (GE), an electrode layer including a plurality of electrodes electrically connected to the graphene layer, and a chalcogenide layer covering at least a part of the side of the graphene layer facing towards the gas environment (GE).
1. A gas sensor for measuring a concentration of carbon dioxide in a gas environment (GE), the gas sensor comprising:
a graphene layer having a first side facing towards the gas environment (GE);
an electrode layer comprising a plurality of electrode electrically connected to the graphene layer;
a chalcogenide layer covering a part of the first side of the graphene layer facing towards the gas environment (GE); and
a passivation layer, which is a different material than the graphene layer, wherein the passivation layer is selectively disposed directly on the first side of the graphene layer that is not covered by but in direct contact with the chalcogenide layer; wherein the chalcogenide layer is deposited before the passivation layer and the chalcogenide layer is exposed to the GE.
2. A gas sensor according to claim 1 , wherein the chalcogenide layer comprises a metal chalcogenide.
3. A gas sensor according to claim 1 , wherein the chalcogenide layer comprises a chalcogenide nanoparticle layer.
4. A gas sensor according to claim 1 , wherein the passivation layer is impermeable to an interference gas of the gas environment.
5. A gas sensor according to claim 1 , wherein the passivation layer comprises chemically modified graphene.
6. A gas sensor according to claim 1 , wherein the passivation layer comprises a hydrophobic polymer.
7. A gas sensor according to claim 1 , wherein the passivation layer is selectively gas-permeable for carbon dioxide.
8. A gas sensor according to claim 1 , wherein the graphene layer comprises chemically modified graphene.
9. A gas sensor according to claim 1 , wherein the graphene layer comprises a graphene floc layer.
10. A gas sensor according to claim 1 , wherein the graphene layer comprises a continuous graphene layer.
11. A gas sensor according to claim 1 , wherein the graphene layer, the electrode layer and the chalcogenide layer are arranged on an insulator layer and a substrate layer, wherein the insulator layer is arranged in such way that the graphene layer, the electrode layer and/or the chalcogenide layer are electrically isolated from the substrate layer.
12. A gas sensor according to claim 11 , wherein the substrate layer comprises an electrical heating element embedded within the substrate.
13. A gas sensor according to claim 1 , wherein the electrodes are arranged on a second side of the graphene layer, opposite the first side of the graphene layer facing away from the gas environment (GE).
14. A method for manufacturing a gas sensor for measuring a concentration of carbon dioxide in a gas environment (GE), the method comprising:
providing a graphene layer having a first side facing towards the gas environment (GE);
providing an electrode layer comprising a plurality of electrodes electrically connected to the graphene layer;
providing a chalcogenide layer covering a part of the first side facing towards the gas environment (GE) of the graphene layer; and
forming a passivation layer, which is a different material than the graphene layer, wherein the passivation layer is selectively disposed directly on the first side of the graphene layer that is not covered by but in direct contact with the chalcogenide layer; wherein the chalcogenide layer is deposited before the passivation layer and the chalcogenide layer is exposed to the GE.