Hydrogenated Si–O–C nanoparticles: Synthesis, structure, and thermodynamic stability

In the present work, for the first time, the inorganic Si-based materials lacking preexisting mixed bonds (O–Si–C, silicon in tetrahedral coordination bonded to both carbon and oxygen) have been successfully used as starting materials in a laser evaporation/condensation system for making hydrogenated silicon oxycarbide (Si–O–C–H) nanoparticles containing mixed bonds. The obtained materials are characterized by spectroscopic, microscopic, and calorimetric measurements. Thermodynamically stable 5–10 nm amorphous Si–O–C–H particles with a complex structure containing a combination of pure and mixed Si-based tetrahedral units (SiOiC4−i;i= 0–4), and a considerable amount of Si–OH and C–H bonds have been synthesized. The nanoparticles possess high surface areas (428–467 m2/g), suggesting potential use in functionalities requiring high surface to volume ratios. In addition, making thermodynamically stable Si–O–C–H ceramics using a pathway different from the polymer route raises the likelihood of formation of similar carbon containing compounds in the planetary accretion and the Earth’s interior.