Silver tellurides (Ag–Te) are promising low-temperature thermoelectric materials because their transport properties can be tuned by subtle compositional variations and nanostructuring. Here, we report a stirring-assisted hydrothermal route that enables controlled synthesis of n-type and p-type Ag–Te nanostructures by adjusting the Ag:Te precursor ratio and hydrodynamic conditions. Samples with Ag:Te ratios of 2:1 (Ag2/Te1) and 1:2 (Ag1/Te2) were synthesized at 120°C for 12 h, varying the stirring speed from 0 to 2000 rpm. X-ray diffraction confirms Ag2Te as the dominant phase for Ag2/Te1 across all conditions, while Te-rich Ag1/Te2 forms a composite mainly consisting of Te and Ag-deficient Ag5−xTe3. For morphology control, the stirring speed significantly alters the microstructural network of the Ag–Te. Moderate stirring (~500 rpm) promotes an interconnected nanowire/nanorod network, whereas higher stirring speeds introduce morphological disruption and secondary phases. Finally, room-temperature transport measurements show that 500 rpm maximizes the power factor for both conduction types: 207.31 μW/mK2 for n-type Ag2Te and 95.83 μW/mK2 for p-type Te/Ag5−xTe3. This work suggests that controlling the molar ratio of precusors and hydrodynamics during synthesis is a critical factor in optimizing the thermoelectric efficiency of silver tellurides.
Lee et al. (Thu,) studied this question.