Potassium fluoride,anhydrous
           Potassium fluoride,extra pure
           Potassium fluoride,Granular
           Silicon Dioxide
           Hydrofluoric acid
           Synthetic Cryolite
           Potassium Fluoaluminate
           Ammonium bifluoride
           Potassium Bifluoride
           Aluminium fluoride
           Sodium fluoride
           Potassium Fluorosilicate
           Fluorosilicic Acid
           Sodium silicofluoride
           Potassium Hydroxide Flakes
           Magnesium Fluoride
           Magnesium fluorosilicate
           Barium Fluoride
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We have prepared silicon oxycarbides by the pyrolysis of siloxane polymers at a maximum temperature of 1000 °C. The resulting silicon oxycarbides are networked glasses which we believe also contain some graphene sheets. After washing in a dilute solution of hydrofluoric acid for times between 2 min and 24 h, these materials lost, at most, 40% of their mass. Powder X-ray diffraction (XRD), small-angle scattering (SAX), BET surface area measurements, elemental analysis, and silicon K-edge X-ray absorption spectroscopy (XAS) were used to determine the physical structure of the bulk material and the local chemical environments of the Si atoms. It was found that a microscopic pore network was created in the material upon HF washing. The number of pores, but not their size, increased with HF washing time. The HF etching revealed a passivating layer, which we believe consists mainly of silicon and carbon, that prevented further etching of the material. The electrochemical behavior of these materials in Li batteries was not affected by the radical changes in surface chemistry.