Non-hydrolytic sol–gel synthesis and electrochemical characterization of tin-based oxide aerogels

A non-hydrolytic sol–gel approach was utilized to create tin oxide and tin–aluminum binary oxide aerogels with high porosity (90%) and high surface area (300 m2/g). XRD data from single-phase tin oxide aerogel indicates the growth of SnO2 crystallites between 150 and 400 °C in air, accompanied by a substantial reduction in surface area. Heated tin oxide aerogel exhibits comparable reversible specific capacity (390 mAh/g) comparable to that of a commercially obtained SnO2 reference (420 mAh/g). By mixing tin and aluminum precursors, binary oxide aerogels were created in which the crystal growth of tin oxide domains was suppressed until higher temperatures. The tin oxide phase in this mixed system remains electrochemically active towards lithium insertion and exhibits excellent reversibility during cycling.