Rapid synthesis of Ag2Se dendrites with enhanced electrical performance by microwave-assisted solution method

Abstract

Ag₂Se dendrites and nanoparticles were successfully fabricated through a rapid one-pot microwave-assisted solution method using EDTA as complexing agent and formamide as solvent and reducing agent. The as-prepared samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS) and thermogravimetry-differential thermal analysis (TG-DTA) techniques. On the basis of the experimental observations, an in situ template growth mechanism was proposed to explain the formation of the Ag₂Se dendrites and nanoparticles. Moreover, the electrical resistivity and Seebeck coefficient were investigated over the temperature range of 300–600 K to determine the impact of particle size and morphology on the electrical performance. The maximum power factor of 1.84 × 10⁻³ Wm⁻¹ K⁻² was obtained at 400 K for Ag₂Se dendrites, which is about 20% larger than that of Ag₂Se nanoparticles. The reasons of enhanced electrical performance were also carefully discussed in the paper.