Not the model I bought, but most portable externals can be opened up and the hard drive can be used. Buyer beware though, it depends on the interface and the passport has a in-built SATA to USB which won't work.
This is a Real easy to upgrade though, I've done it. Just search for ps4 hard drive upgrade on YouTube to watch how it is done. The hard part of any of these hard drive upgrade projects is salvaging the case of the external HD so you can pop back in the 500 GB hard drive that came with your PS4 so you get a new external hard drive. You also need to back up your data but there is a new option on the ps4 to back it up quicker, Google it for more details.
Make sure to check the model is thin enough to fit the PS4 though and has the appropriate interface to plug in to the PS4, to be honest, I have heard the Passports are not eligible. I would do some research before you commit. If you just want one that will work, I would recommend this Seagate if you are worried about compatibility, this model linked here is the most common one used for PS4 upgrades and will work 100%. I am using my WD Passport as an external on my Xbox one.
http://www.bestbuy.ca/en-CA/product...spx?path=ca5594b08401f401d7c878bc19a1df42en02