Tags can not be activated and deactivated. Once a passive ultrahigh-frequency (UHF) tag has been deactivated, that tag is essentially dead.
However, Impinj offers a chip that has private and public modes; public mode hides proprietary data and replaces it with a random serial number that means nothing. When a book is returned to a library, its tag can be switched to private mode, in which the data would be readable by staff members within the library. This could work well for your situation.
Here is an article that might be relevant to you: Impinj Launches New High-Performance RFID Chips. I hope this helps.
—Mark Roberti, Founder and Editor, RFID Journal
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