Key developments in magnesiothermic reduction of silica: insights into reactivity and future prospects

Porous Si (p-Si) nanomaterials are an exciting class of inexpensive and abundant materials within the field of energy storage. Specifically, porous Si has been explored in battery anodes to improve charge storage capacity, to generate clean fuels through photocatalysis and photoelectrochemical processes, for the stoichiometric conversion of CO2 to value added chemicals, and as a chemical H2 storage material. p-Si can be made from synthetic, natural, and waste SiO2 sources through a facile and inexpensive method called magnesiothermic reduction (MgTR). This yields a material with tunable properties and excellent energy storage capabilities. In order to tune the physical properties that affect performance metrics of p-Si, a deeper understanding of the mechanism of the MgTR and factors affecting it is required. In this perspective, we review the key developments in MgTR and discuss the thermal management strategies used to control the properties of p-Si. Additionally, we explore future research directions and approaches to bridge the gap between laboratory-scale experiments and industrial applications.