Flourescent dyes won't need an external source of energy, but they are not easy to get They are still in the research stage. Maybe you could contact the Rutgers folks in the article to buy the dyes they are using. See if you can find edible these food colors that are routinely added to food or pharmaceuticals: Allura Red, Sunset Yellow, Brilliant Blue, Fast Green and Tartrazine, a yellow-colored dye. Read more about flourescent food dyes at: https://phys.org/news/2015-02-fluorescing-food-dyes-probes-quality.html#jCp
Another idea- commonly available neon colored dyes could look like they glow. These super-bright hues won't give off their own light for a true glow, but will reflect lots of ambient light.
Disney has done a lot of research on this topic, and they've gone with the LEDs or lightsticks inserted into food. The effect is a safe desert with a lightup keepsake: Disney's InfinityAide or Fairy Floss or LightSaber Churros Perhaps bake your pie in two pieces and then drop a glowing light cube inside your lemon filling and then plop on the pre-baked top? Or maybe make a crust that has holes in it that you can poke a few small lightsticks into.
The most common way to get a glow in the dark effect is to use UV because many food safe ingredients (such as tonic water and caramel) respond to UV wavelengths. The UV causes the ingredient to give off its own light (fluoresce). However, I'm not sure if the quinine from tonic water will survive baking. Lots of websites show people using tonic water on their cup/cakes after covering them with jello.
Another route is using bioluminescence, but its not for the squeamish. You could make powder from organisms that have phosphorescence (glow worms). Crush them, sprinkle them on top of lollipops or you could try crushing up GloFish:
https://www.foodprocessing-technology.com/features/featureglowing-sushi-experimenting-futuristic-food/ These will glow in the dark, but only faintly. If you use blacklight the bioluminescent ingredients will respond more brightly, of course. Here's some nice pictures of flourescent dye from glowing jellyfish for glow beer using a yeast that responds to "UV or blue light" according to gizmodo.
Also check out the links at the bottom of that Eater article on glowing beer, glowing udon noodles, and glowing ice cream.
Anyway, you could avoid UV and go for blue light. Some things that will flourescen under UV will respond to blue or purple LED light.