ANSWER:
Yes, it’s an innovation to raise the hands and make dua after salah.
If you make the dua after salah once in a blue moon without raising hands, it’s OK but you must not make it a habit as this is the time for doing the prescribed dhikr and you should make dua in your sujood and in the last tashahud before making Salam.
https://youtu.be/hYToZVeAl20