I have used recuva from piriform with good success. There is a free version and a more advanced pro version. Here is a link -
https://www.piriform.com/recuva. You should see 2 download buttons: [Download Free Version] and [Get Recuva Pro] Recuva is a windows app.
Another free file recovery app is Test Disk. Test Disk is rated very high, but it is a command line tool. So not as easy as a windows app.
There are quite a few other, free, file recovery apps out there. Just google for "best free file recovery apps". I hope this helps.
;-)