The normal, standard, and expected form is to use the plural form with the negative.
There are no cats.
However, if you need to be very emphatic, there are times when the singular would work.
A: I saw a cat
B: There are no cats here.
A: Look, right there. It's a cat.
B: No, it's not. That's not a cat. Really, there are no cats here.
A: I'm looking right at it. It's a cat!
B: I'm telling you, there is no cat here! That's my purse! God, buy some glasses, would you?!