In Qt Creator, you could use the syntax highlight definition files from Kate, more details in Qt Creator Doc: Semantic Highlighting.

Where could we get more?

Here it is: KDE-FILES.org: Kate Highlighting. Just download one, and move it into ~/.config/Nokia/qtcreator/generic-highlighter, restart your Qt Creator, it works.

Want to write your own?

This is a good material to read, Kate: Writing a Syntax Highlighting File.