I wonder if they could put solar panels on the wings.

If you do some reading, until they get batteries 1/10 as light and 5 times as much capacity as they have right now it wont happen. Right now the best battery is 300 watts per kilogram, jet fuel is 12000, or 40 times more.
Plus planes get lighter as they go, that a huge safety thing for landing, many time planes circle the airport a few times to burn off extra weight just to land. Now you will have a plane trying to land that was just as heavy as when it took off.

There are better ways, work on efficiency, emissions and other things. But commercial electric flight wont happen until we have MR Fusion on the plane.

If you read, they are mostly talking about short flights, under an hour. Use trains for that, sure it will take 2 hours, but it can also carry 20 times as many people.

As for solar panels on the wings, I once did the math to see what it would take to make a solar tractor trailer. It worked out to panels about 5 times the size of the truck for high way speed on flat ground. As soon as you put a hill in front of the truck it was 30 times the size.
https://spectrum.ieee.org/electric-airplanes-wont-make-much-of-a-dent-in-air-travel-for-decades-to-come

Still have the advantage of liquid fuel -- ammonia should be the best contender there, since it forms only water and nitrogen in a fuel cell. Ammonia is basically a more convenient way of transporting liquid hydrogen, without the super-low temperature.

that it'll be quite some time before we see electric planes in mass use.

But at least it's somewhere on the horizon!