carbon fiber is both strong and brittle. it’s strong along the length of the fibers, but weak at right angles to the fibers. it’s also not able to absorb much energy before it breaks. pedals are subject to a lot of abuse, especially when grinding, and CF can’t handle this kind of abuse
you should do a little research the next time you get a “bright idea” so you can find out for yourself how feasable the idea is… you might even learn something to help improve your idea, at the very least you’d be able to express your idea to others a bit more intelligibly
thirty seconds of googling got me to this page that describes the properties of polymers; carbon fiber is one example of a polymer. there’s everything you need to know at this page that will tell you why CF pedals won’t work
google is your friend. so is the “search” link. use them and you will be rewarded.