If you have PDF files that are readable (OCR), Zotero can extract the necessary metadata from the document to create a source record.
Note: if the pdf format is a static image then this process won't work as well. You have some options:
If you are syncing with your online account, attached files take up significant space. To avoid running out of space, uncheck the sync full-text content to prevent files from being uploaded to your online account.
Illinois State University
Campus Box 8900
201 North School Street
Normal, Il 61790-8900