I had left a few samples of electrospun Carbon fiber mats outside for a while and they seemed to have completely different electrochemical behaviors before and after their storage in open air. I guess the outside atmosphere storage had to do something with it (maybe, surface reaction or pollution) and I am looking for a cleaning behavior which will not affect the carbon fiber mats as it is (very delicate). Could someone kindly suggest any method or procedure that has been followed or could be followed to clean them?