Hi Aioa
Sounds like an interesting, although possibly exciting/risky project
No experience or good knowledge with your particular set-up or aluminium nitrate, so my comments should not be relied upon.
First, aluminium nitrate is a strong oxidising agent so I would have concerns with mixing/dissolving in isopropanol or other organic solvent.
(fuel + oxidant =
)
Really not sure on stability here, but I sense risk. If you must
very small scale first
May be worth just trying water based solution by itself. Although, this will be acidic so you will need to be careful what this comes into contact with.
Make sure you have good extraction/personal protective equipment, as I'm sure you know oxides of nitrogen will be a bye product as well as your intended nano-sized aluminium oxide.
I would certainly be interested in how you get on and just advise to keep it really small scale to start with, just in case the worst happens. Good luck.