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In this study tin-functionalized silicon oxycarbide, Sn/SiOC, composite anode materials are synthesized using a carbon-rich polysiloxane as the preceramic polymer and nano-sized SnO2, which converts to metallic tin via carbothermal reduction at approximately 700 °C. The in-situ Sn formation leads to a uniform distribution of tin particles within a carbon-rich SiOC matrix. Raman spectra show no significant changes despite the carbothermal reduction of SnO2. The composite material provides a stable reversible capacity of 234 mAh g-1. By adjusting the composition and pyrolysis temperature a reversible capacity of 131 mAh g-1 at a high current rate of 2380 mA g-1 is achieved.

In the last decade, Sodium-Ion-Batteries (SIB) started to gain interest as a possible complementary candidate to support the overburdened lithium technology, but the manufacturing of a proper anode material is one of the challenging factors for the development of performing SIB. Among others, porous polymer-derived ceramics have been widely explored as suitable anodes despite the production of such materials being time and energy-consuming. In this work, we investigate the feasibility of adopting a low-cost ultra-fast high-temperature pyrolysis for the ceramic conversion of a polymer-derived SiOC aerogel to be employed as anode material. A comprehensive study including N2 physisorption, 29Si MAS NMR and Raman spectroscopy provides the insights of the effect of ultra-fast and conventional heating rates (i.e., 200 °C·s−1 vs. 5 °C·min−1) on the microstructural features and ceramic yield of the SiOC aerogels. As a consequence of the ultra-fast heating rate, a compositional drift towards oxygen-rich SiOC is observed and discussed. The electrochemical performance of both ceramics has been tested and related to the observed compositional differences, revealing a stable capacity of 103 mAh·g−1 for the ultra-fast pyrolyzed SiOC anode, and 152 mAh·g−1 for SiOC ceramized at 5 °C·min−1.

The present review introduces a class of ceramic nanocomposites that contain carbon as disperse phases and exhibit piezoresistive behavior. After a brief introduction in which the piezoresistive effect is described and selected principles for the design of piezoresistive sensing devices are highlighted, various carbon-containing ceramic nanocomposites are presented and discussed in the light of their preparative access as well as their piezoresistive behavior. Emphasis is put on carbon-containing ceramic nanocomposites in which the dispersed carbon phase is generated in situ during a thermal treatment process, which allows tunable carbon contents and crystallinities, along with a highly homogeneous dispersion of the carbon phase in the ceramic matrix. The piezoresistive carbon-containing ceramic nanocomposites presented here are furthermore critically discussed within the context of their potential use as force/strain/pressure sensing materials for applications at ultrahigh temperatures and in hostile environments.