A comprehensive review of different thermal energy storage materials for concentrated solar power has been conducted. Fifteen candidates were selected due to their nature, thermophysical properties, and economic impact. Three key energy performance indicators were defined in order to evaluate the performance of the different molten salts, using Solar Salt as a reference for low and high temperatures. The analysis provided evidence that nitrate-based materials are the best choice for the former and chloride-based materials are best for the latter instead of fluoride and carbonate-based candidates, mainly due to their low cost.

Two dense biphasic ceramics, with a hypereutectic composition of 30 wt % CaSiO₃–70 wt % Ca₃(PO₄)₂, were synthesized by a solid-state reaction of homogeneous pressed combinations of previously synthesized synthetic CaSiO₃ and Ca₃(PO₄)₂ powders. The objective was to produce a dense structure to generate large enough in situ pores for the ceramic to be used in tissue engineering. To develop such a structure, two grain sizes of CaSiO₃ were used (63–100 µm and 100–150 μm) and some of their properties were studied in vitro, as they are relevant for tissue engineering. X-ray diffraction analysis, μ-Raman spectroscopy, diametrical compression test, and scanning electron microscopy with elemental mapping showed a coarse-grained homogeneous microstructure for the materials, which consisted of wollastonite (α-CaSiO₃) and tricalcium phosphate (α-Ca₃(PO4)₂), with adequate mechanical properties for implantation. In vitro bioactivity was evaluated in simulated body fluid (SBF) by exploring a hydroxyapatite (HA)-like formation. The results showed that tricalcium phosphate grains dissolved more preferentially than those of wollastonite, but not fast enough to leave a pore before the surface was coated with an HA-like layer after soaking only for three days. Biocompatibility was evaluated by in vitro cell experiments, which showed cell proliferation, adhesion, and spreading on the ceramic surface. This ceramic is expected to be used as a bone graft substitute.