Can I use 12/2 NM-B wire for basement outlets?
You can use nonmetallic sheathed cable in basements, as long as you follow a few rules.  

If you're using 12 AWG cable, and you're installing the cable at angles to the joists. You'll have to pull the cable through bored holes, or along running boards. You cannot staple the cable along the bottom of the joist.

When you come down the wall, you'll have to protect the cable in some way. This could be in conduit, or by installing a wood framing member (2x4) for the cable to attach to.  If you use the framing member, the cable will have to attach to the side not the face of the member.

This answer will provide code references.



Yes, you can use 12 AWG conductors with 15 ampere rated receptacles and switches.  You'll have to use the screw terminals, instead of the push-in terminals. As most push-in terminals on these devices, are only rated for 14 AWG conductors.