Synthesis of silicon carbide using concentrated solar energy

•Synthesis consisted in 5 steps, where the last 2 steps were done using solar energy.•Last step of the synthesis was done at 1500°C in argon atmosphere.•Characterization indicates that SiC obtained is composed of cubic type SiC (β-SiC).•It is feasible using concentrated solar energy for the synthesis of SiC with lower CO2 emissions.•This novel method is reported for the first time. Silicon carbide (SiC) has been prepared successfully using concentrated solar energy provided by the IER-UNAM solar furnace. This has led to the development of a low CO2 emissions process for the production of this material via carbothermic reduction of a silica/carbon (SiO2/C) nanocomposite, which has shown a more reactive carbon for formation of composite, being more thermally stable. Silica (obtained by a sol–gel process) and sucrose were used as precursors of silicon and carbon, respectively, at a temperature of 700°C in controlled atmosphere (nitrogen) for the formation of the SiO2/C composite. This composite was used in a second step to obtain SiC at a temperature of 1500°C, in argon atmosphere. The experimental setup used a Pyrex® glass spherical vessel designed to work with concentrated solar power and controlled atmospheres. The structure and morphology of the solar obtained SiC were analyzed with FTIR, XRD, TGA/DSC, SEM and TEM techniques. Results show that it is feasible to use concentrated solar energy for the synthesis of SiC. The solar SiC obtained is nanostructured and is mainly β-SiC.