MissingComponentException: There is no 'Material' attached to the code example

Example: There is no 'Material' attached to the ui unity

Aha! So the material is never actually a component of an object. Its an extension of the renderer component.
Got it, thanks!

GameObject go_child = go.transform.FindChild("dummyspown").gameObject;
go_child.GetComponent<Renderer>().material.SetColor("_Color", Color.red);