My Dutch wife living in Spain wants to deposit some money into an interest-bearing savings account in the Netherlands. Is there a comparison website available to help locate a suitable one?

You mean something like this: https://www.geld.nl/sparen/spaarrente/overzicht
Many options are showing when searching for "spaarrente vergelijk". I assume that your Dutch wife can speak Dutch...

Thank you, that's what I'm looking for. Yes, she speaks Dutch and my browser does a decent job of translation too. Much appreciated.

You may not be able to open a savings account on its own as most banks insist on a current account in parallel.