Inline Fan silencer?

Hey, Is there any Type of Inline fan silencer or something thay make That goes on the Exhaust Side to Reduce the Noise the Exhaust side is making?
I have a 6in Vortex Fan in my room and i need to quiet it down a little bit..
Thanks for the Help..

I have one in my roof / attic as that where my grow is and found that wrapping roof insulation around the fan helped and putting it onto an old pillow dulled the sound a fair bit. It right above my bedroom and my wife was complaining, i can still hear it but its better.

Hope this helps a little