I can't take credit for this as I read this in a brief hints article in an outdoors magazine perhaps 20 years ago. My wife keeps this one in her recipe box, and it works!
1 cup (8 oz) of drugstore Hydrogen Peroxide
1/2 cup Baking Soda
1/8 cup dish soap.
mix all the ingredients.
assuming it's the family dog who was sprayed, first wet the fur, then rub in the mixture. Very large animals may need more stuff mixed.
almost instantaneously, the stink is gone.
How does it work? The gaseous molecule in the skunk urine that causes the big stink is a long chain including sulfur. It is acidic. Our olfactory receptors are sensitive to the molecule, big time.
The dish soap helps to get past the oils in the animal fur, allowing the liquid to get into the hair fibers. The Baking Soda neutralizes the acid in the urine and the Hydrogen Peroxide attacks the molecular bonds, making the stink molecule smaller.
It'ssimple, easy and works on things like collars, clothing, etc.