See the following article as a suggestion:

https://onlinelibrary.wiley.com/doi/abs/10.1002/adfm.201500314

https://www.sciencedirect.com/science/article/pii/S2211812815002461

https://www.sciencedirect.com/science/article/pii/S2214785315010755

Dear all, these two attached RG links and the attached files give important information on CO2 sensors. My Regards

https://www.researchgate.net/topic/Gas-Sensors

https://www.researchgate.net/publication/286043288_CO2_sensing_layers_for_SAWBAW_devices

Check this one

Article Carbon dioxide gas sensor using a graphene sheet

Please look at the following below links which may help you in your analysis:

https://pdfs.semanticscholar.org/2b45/b7784af0df081cc9b536755639e84865ea29.pdf

https://www.nanowerk.com/nanotechnology-news/newsid=40342.php

Thanks

Graphene hybrid nanomaterials.