Employees not only like to receive rewards from you, but they like to get praise and rewards from their peers in many cases as well. In some situations, this peer-to-peer reward is more valuable because it fosters better teamwork through appreciation.
To foster this culture of peer-to-peer rewards, do a few things:
Set the expectation of gratitude. Model the behavior and let them know they should reward with praise amongst themselves.
Provide a vehicle for peer-to-peer rewards. There are some great systems that companies use, but it doesn't have to be formal. Providing a few minutes in a team meeting for people to share works just as well.
Teach your team how to show appreciation. It is more than saying "thank you", make sure they tie the appreciation to a specific behavior and make it sincere.
There are some things to be wary of as well:
As you first implement this, be patient. The first time you offer a few moments to share appreciation, you may get few (or no) responses. Explain why you are doing this and be patient as people warm up to the practice.
Ensure it does not become "silly". People may start to offer appreciation for things that are small just to do it. For example, if someone thanks another employee for showing up on time, that probably doesn't warrant appreciation (unless the employee had issues with it in the past).
This builds a culture of appreciation and gratitude, but it does take intentionality on your part.