Keep your phone in airplane mode at night, or put it across the room. Some companies sell EMF-blocking chargers, but humans slept fine for thousands of years without phones nearby at all.
You should only sleep with your phone anywhere near you if it's on airplane mode. If it's not on airplane mode, put it as far away from you as you can. There's also companies out there that make devices that let your phone be near your bed and charge that will deflect the EMF from it. I don't know the name of that, but they sent me some a while ago. And there's something to be said for not having your phone on when you sleep. Because when you sleep, unless you're a doctor on call or something, throughout all of human history, people have slept without phones, and it was okay.
