Thermochemical heat storage performances of magnesium sulphate confined in polymer-derived SiOC aerogels

Polymer‐Derived Ceramic Aerogels to Immobilize Sulfur for Li‐S Batteries

“…[2][3][4] The PDC route also allows processing components with difficult-to-obtain microstructure and/or shape: fibers, [5] foams, [6] aerogels, [7] and microlattices/honeycombs. [8] Taking advantage of the high chemical and thermal stability of PDC aerogels and from their easy tailorable composition and porosity (i.e., total porosity and pore size), [9,10] they have been proposed for different applications like matrices for thermal energy storage (TES) to confine high temperature melting and chemically aggressive phase change materials (PCM) [11,12] or as sorbents for water purification. [13,14] Polymer-derived silicon oxycarbides have also shown higher lithium storage capacity compared to conventional graphite-based anodes [15] and SiOC aerogels displayed also very high lithium reversible capacity at very high charging/discharging rates, namely, 300 mAh g À1 at 20 C. [16] Nowadays lithium-ion batteries are used in portable electronics and cars and are proposed as backup storage for many intermittent renewable energy sources.…”

“…Taking advantage of the high chemical and thermal stability of PDC aerogels and from their easy tailorable composition and porosity (i.e., total porosity and pore size), [ 9,10 ] they have been proposed for different applications like matrices for thermal energy storage (TES) to confine high temperature melting and chemically aggressive phase change materials (PCM) [ 11,12 ] or as sorbents for water purification. [ 13,14 ] Polymer‐derived silicon oxycarbides have also shown higher lithium storage capacity compared to conventional graphite‐based anodes [ 15 ] and SiOC aerogels displayed also very high lithium reversible capacity at very high charging/discharging rates, namely, 300 mAh g −1 at 20 C. [ 16 ]…”

Low‐temperature thermal energy storage with polymer‐derived ceramic aerogels

“…With respect to metallic and organic scaffolds, porous ceramics offer chemical inertness, relatively low density and high-temperature stability, thus being also attractive for the containment of corrosive salts. [18][19][20][21] In particular, polymer-derived ceramics (PDCs) are of great interest in this field, as properties like surface area and total porosity of the final products can be easily controlled during the synthesis route, [22][23][24][25] thus giving the possibility to obtain extremely porous ceramics, such as silicon-based aerogels. [26][27][28] As a matter of fact, PDCs are obtained through the controlled pyrolysis of polymeric precursors, which can be chemically engineered to obtain exotic compositions (e.g., SiBCN, SiAlON, and SiCN) with unprecedented functionalities.…”

“…The containment of molten PCMs within porous matrices, thanks to capillary forces, is fundamental to guarantee a shape‐stabilization and to avoid PCMs losses while optimizing the thermal efficiency of confined compounds. With respect to metallic and organic scaffolds, porous ceramics offer chemical inertness, relatively low density and high‐temperature stability, thus being also attractive for the containment of corrosive salts 18–21 . In particular, polymer‐derived ceramics (PDCs) are of great interest in this field, as properties like surface area and total porosity of the final products can be easily controlled during the synthesis route, 22–25 thus giving the possibility to obtain extremely porous ceramics, such as silicon‐based aerogels 26–28 .…”

“…29,30 This article reports the synthesis and the use of polymer-derived silicon carbide (SiC) and silicon oxycarbide (SiOC) aerogels as shape-stabilizers for organic room temperature PCMs. The rationale behind the use of this type of skeleton materials lies on three milestones: (i) both SiC and SiOC aerogels display high pore volume and specific surface area (SSA) and can be synthesized to have over-stoichiometric carbon (i.e., free carbon) in their structure in order to boost the thermal conductivity of the ceramic network (in a previous study, we showed how free carbon can mitigate the rather low thermal conductivity of SiOC when dealing with thermochemical heat storage 31 ); (ii) PDCs aerogels possess a mechanically stable hierarchical porosity 32 in the mesopore-macropore range able to minimize molten PCM losses; (iii) both SiC and SiOC are nontoxic safe silicon-based ceramics.…”