Structural and optical properties of Bi2−xTl _<i>x</i> Se ₃ (x=0.04) nanoparticles for thermoelectric devices application

Bismuth Selenide (Bi 2 Se[Formula: see text] has a wide range of applications in thermoelectric devices. In this regard, Bi[Formula: see text]Tl[Formula: see text]Se 3 nanoparticles were synthesized using a hydrothermal method and their structural and optical properties were studied using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and diffuse reflectance spectroscopy (DRS). The crystal structure and the other lattice parameters including strain ([Formula: see text] and average crystallite size ([Formula: see text] were determined through XRD analysis. The average crystallite size and strain of the developed nanoparticles were calculated to be 20.33[Formula: see text]nm and [Formula: see text], respectively. FTIR confirmed the presence of Bi–Se stretching modes at 438 and 524[Formula: see text]cm[Formula: see text]. The band gap of the nanomaterial was derived using DRS characterization. Transport properties were examined in the temperature range of room temperature to 430[Formula: see text]K. These findings provide insight into their potential for future applications in thermoelectric technologies.