A blackbody is an object that absorbs all of the radiation that it receives (that is, it does not reflect any light, nor does it allow any light to pass through it and out the other side). The energy that the blackbody absorbs heats it up, and then it will emit its own radiation. Platinum black is the kind of element that gets absorbs energy and get heated up very fast.soa body which is coated inside with platinum black ,which has a small hole in its wall can act as a black body.