Microwave-assisted hydrothermal synthesis of Zn2SnO4 nanostructures for photocatalytic dye degradation

Zinc-tin oxide (ZTO) material system possesses a wide range of attractive properties for a new generation of multifunctional nanodevices. It can crystallize in Zn2SnO4 and ZnSnO3 phases, with different types of nanostructures possible for each phase. Each has unique properties suitable for applications in catalysis, sensors, transistors, memories, or energy harvesting devices [1,2]. In previous works an in-depth study on the influence of the chemico-physical parameters of a seed-layer free hydrothermal synthesis in a conventional oven (24 h at 200 °C) allowed to control the achievement of different types of ZTO nanostructures [3,4]. An alternative route to circumvent the inconveniently long synthesis durations in a conventional oven is the microwave heating assisted synthesis, which allows to achieve accelerated chemical reactions [5]. As such, in this work it is shown that Zn2SnO4 nanoparticles, octahedrons and nanoplates are obtained by microwave-assisted synthesis with reduced processing times of up to 22 h, while still yielding reproducible and homogeneous results. The photocatalytic activity of the Zn2SnO4 nanostructures produced using the microwave system are evaluated for rhodamine B degradation under UV light, being observed a better performance for Zn2SnO4 nanoparticles with >90 % of degradation in 2.5 hours.