Investigation of electrical transport properties in solution-processed Bi2Se3–AgMnOOH nanocomposite

In this paper, we report the fundamental electrical transport properties measured in Bi2Se3–AgMnOOH nanocomposite disc, which is prepared for the first time by convenient low temperature solution-phase chemistry in conjunction with redox-mediated methodology. The comparative structural and morphological analyses for the nanocomposite with pristine Bi2Se3 are comprehensively investigated by different material characterization techniques. The results demonstrate the successful in situ composite fabrication between the Bi2Se3, Ag and γ-MnOOH components. Besides, the present work introduces a systematic approach for the examination of electrical transport properties in Ohmic and non-Ohmic regimes over a wide temperature range. The results from the room temperature transport measurement exhibited that the nanocomposite demonstrated non-linearity after a certain current I0 (onset current), whereas Bi2Se3 was linear in the entire measured current range. An enhancement of the conductance was observed for Bi2Se3–AgMnOOH compared to the pure Bi2Se3 material, which is credited to the composite effect. The onset exponents xT (DC conductance) and xf (AC conductance) with phase-sensitive character demonstrate different values below and above 180 K separating two different phases with different conduction mechanisms. Also, flicker noise analysis established the correlation between the DC conductance in terms of Ohmic to non-Ohmic transition after the onset voltage V0. This transition phenomenon from Ohmic to non-Ohmic behaviour is explained from the structural point of view of the nanocomposite. The present investigation highlights the importance of using the bottom-up solution-phase strategy for the synthesis of high quality Bi2Se3-based nanocomposites for transport studies and their possible future applications.