Vanadium dioxide (VO₂) sol-gel synthesis and characterization.

Vanadium dioxide (VO₂) is a thermochromic material well-known for its reversible metal-insulator transition (MIT) near 68°C, making it a prime candidate for applications in smart windows, sensors, and energy-efficient coatings. This preliminary study investigates the sol-gel synthesis of VO₂ ceramics, a cost-effective and scalable method that allows fine control over stoichiometry and doping. The sol-gel process involves the hydrolysis and polycondensation of vanadium precursors, followed by thermal treatment to induce crystallization of the desired VO₂ phase. We optimize various parameters, including precursor concentration, aging time, and annealing temperatures, to achieve high-purity VO₂. Conductivity and optical reflection measurements of the pressed ceramics are used to observe the metal-insulator switching.