Synthesis of self-assembled spherical ZnFe2O4 nanomaterials by the premixed stagnation flame method for highly sensitive acetone sensor

Abstract

The efficient and reliable detection of acetone is critical for industrial safety, environmental monitoring, and human health. Separately, ZnFe2O4 particles were synthesized by using the premixed stagnation flame method and the co-precipitation method. The premixed stagnation flame method was used to create self-assembled spherical ZnFe2O4 nanoparticles with uniform morphology, polycrystalline morphology, and excellent phase purity. The effect of the gas-sensitive performance of these sensors for two routes on acetone vapor was compared. The sensor synthesized using the premixed stagnation flame method had a response value of up to 26 at 235°C for 100 ppm acetone vapor. It revealed outstanding reproducibility, stability, and selectivity for acetone vapor, which is attributed to the 10 nm "lychee-like" particle structure uniformly dispersed on the surface of the 400–500 nm spherical particles, forming a unique self-assembled structure. The self-assembled spherical structure has a large specific surface area, abundant oxygen adsorption, and oxygen vacancies, which effectively increases the reaction sites and electron mobility inside and outside the nanoparticles. The premixed stagnation flame method of producing spherical ZnFe2O4 nanoparticles presents a viable method for developing extremely sensitive, fast-responding, and selective acetone vapor sensors.