Self-templating Synthesis of Silicon

ΓÇó Hydrofluoric acid free process makes it environmentally friendly ΓÇó Reduces cost by eliminating solid silicon templateΓÇó Numerous applications in lithium-ion batteries

Background:Porous silicon materials are common in optoelectronics and sensoring due to their light emitting properties. These materials are also common in drug and gene delivery due to their high porosity and biocompatibility. Current research has identified porous silicon materials as an effective way to compensate the huge volume change (300%) of the silicon anode during the electrochemical process in lithium-ion batteries. There are currently two methods to produce porous silicon materials including anodisation and stain etching. However, both of these methods need a solid silicon precursor or template, hydrofluoric acid, are high cost, and are not very efficient. Invention Description:The method provides a mesoporous silicon material prepared by a template-free and hydrofluoric acid-free process. This process uses the reduction of a silicon-halogenide precursor with an alkaline alloy. The resulting silicon-salt matrix can then be annealed for pore formation and crystallite growth. Not only does this reduce the cost of traditional processes by eliminating the need for a template/precursor, but it also eliminates the use of hydrofluoric acid, which is not environmentally friendly.

USA