“…This oxide layer prevents further oxidation of Si, so significant oxidation of Si does not occur at room temperature. However, in aqueous solutions at high temperatures, Si powders could occur significant oxidation, and the oxidation rate becomes slower with increasing oxidation time. , The Gibbs free energy (Δ G ) of the oxidation reaction is negative at 120 °C, indicating that the reaction is spontaneous (Figure S1). Thermal analysis of Si@SiO 2 -15 shows an exothermic peak at 1388 °C (Figure b), implying that SiO 2 starts to change from an amorphous to a crystalline structure.…”