Using your rfkill script, I was able to toggle bluetooth as well.
As root, I created the file /etc/acpi/actions/bluetooth.sh
with the contents of your rfkill script. I then made the file executable from Nautilus as root by changing permissions.
Next I ran acpi_listen in terminal to see what Fn+F9 showed. I was getting button/f24 F24 00000080 00000000
. I then created the file /etc/acpi/events/bluetoothconf
as root with the following contents:
Finally I ran #acpid restart. Now my hotkey combo toggles the bluetooth radio on and off.
An alternative for some might be to create a custom keyboard shortcut in System Settings > Keyboard > Shortcuts > Custom Shortcuts, however this was not working for me with the Fn+F9 shortcut.
EDIT: After reboot I got some SELinux alerts. Had to run audit2allow 3 times (IIRC) to get SELinux to allow the rfkill script to run.