Can nicotine-free liquid be used in any vape?

Well it all depends on the vape you buy. If you buy a vape where you have to put in your own e-liquid then yes. It is rare that these pre-filled disposable vapes come in nicotine free. 

Most e-liquid sold by itself is available in 0mg nicotine or no nicotine. 

As long as you buy a vape where you can put your own e-liquid it in you should be fine. 

I will worn you that vaping is not healthy habit and there are other things you should do rather than vaping but I doubt I can say anything to stop you even as an ex-smoker who is glad to finally never have to suck on anything but clean air after quiting cigs with a vape and quiting vape entirely