I have a problem removing thin carbon soot coatings from microscope glass slides. In general, this material is very brittle, however, after certain chimney modification it becomes robust (see Esmeryan et.al Rapid Synthesis of Inherently Robust and Stable Carbon Soot Coatings). Moreover, the conventional method for removal based on ethanol treatment, followed by soap treatment with hot water does not work in this situation. There is still some soot on the surface that is very well adhered to it. What kind of chemical should i use? Thanks in advance.