From a quick search [1] it looks like the process for spin coating PbI2 is a bit more involved than just spinning a substrate. There are several other solvents

From a quick search [1] it looks like the process for spin coating PbI2 is a bit more involved than just spinning a substrate. There are several other solvents an a boiling process which will have byproducts but ones that have their own recycling process. [1] http://www.rsc.org/suppdata/ra/c3/c3ra43228a/c3ra43228a.pdf http://www.rsc.org/suppdata/ra/c3/c3ra43228a/c3ra43228a.pdf