Hey Timothy, there's a good thread on these forums in regards to how to collaborate with someone: https://forums.tapas.io/t/how-to-actually-collaborate-with-an-artist-writer/19682
I'd definitely recommend giving it a read and refining your pitch. There's a few reasons why an artist may team up with you without being paid (practice, for example) but you'll have a better chance of finding someone if you can elaborate on the project you have in mind.
I'd also suggest forgetting about multiple chapters for now. Go small to begin with and be specific about what you're looking for. Your idea sounds interesting but I think you could push the hook a little more; give a potential artist something they can sink their teeth into.
Include any writing examples too, if you have them. Any artist will want to see how well you can write before anything else.
Web comics are demanding work for an artist and not being paid for that work isn't very attractive; so try to make your pitch as irresistible as possible.