Yes. All QF FF program rewards are one way. You can book as one way, or if you like a return at the same time (if you can find a reward seat). Getting business class a Oz –US reward is very hard. Helps if you are top tier (Platinum) in the QF FF program.

QF reward tickets are far from "free". Need to pay $$ for fuel surcharges and taxes.

If you are trying to get an reward flight using AA points you are subject to the AA program rules