Seeking Guidance on Ontologies and Taxonomies in Materials Science

Hello, I am material scientist at MIT working on creating a knowledge graph of materials. I am new to ontologies and the semantic web in general. I would like to understand ontologies/taxonomies and what an ontologist/taxonomist does in general. Would someone in this channel be able to talk with me for 30 minutes while I ask you some questions about your work? Please feel free to DM me to set up a time. Thanks so much!