A facile synthesis, structural, morphological and electrical properties of Bi2Se3 nanomaterials

Bi 2 Se 3 nanoparticles were synthesized using the solvothermal method. The structural and morphological characterizations were conducted using XRD, HRSEM and Raman spectroscopy, while electrical studies performed at room temperature were analyzed using impedance spectroscopy and cyclic voltammetry. Phase formation was confirmed through XRD measurements, and the average crystallite size was found to be 25 nm for the as-prepared sample and 37 nm for the annealed sample at 650 °C/12 hours. The Raman spectrum of Bi 2 Se 3 obtained with 785 nm laser excitation was also performed to investigate the four Raman active modes of this sample. The three optical phonon modes were distinctively observed at ~ 124 cm -1 , 262 cm -1 and 524 cm -1 . The redox behaviour was due to the conversion of Bi 3+ into Bi 2+ and Bi metallic states. Bi 2 Se 3 nanoparticles annealed were modified on the GCE (Bi 2 Se 3 NPs/GCE), resulting in higher redox peak current with IPa = 0.021(µA) and IPc = − 0.144 (µA). It showed the very high resistance as well as the grain effect curve behaviour. The optical band gap energy of 3.47 eV was determined from the corresponding UV-Visible spectrum.