personnel vs personnel department

personnel and personnel department both are nouns.

Word	Noun	Adjective	Verb	Adverb
personnel	Yes	No	No	No
personnel department	Yes	No	No	No

As nouns, personnel and personnel department are synonyms defined as:

personnel and personnel department: the department responsible for hiring and training and placing employees and for setting policies for personnel management

Other synonyms of personnel include personnel office, staff office.

personnel (noun)	personnel department (noun)
group of people willing to obey orders	the department responsible for hiring and training and placing employees and for setting policies for personnel management
the department responsible for hiring and training and placing employees and for setting policies for personnel management