Temperature-Dependent Charge Transport and Hall Effect Behavior in MoS₂ Nanostructures in (270–345)°K Temperature RangePages 202-215
Hussein AlHussein Abstract:
This study systematically explores the thermal transitions in electron transport mechanisms within molybdenum disulfide (MoS₂) nanostructures and sheets in the 270–345 °K thermal range, using four-probe Hall effect measurements under a static magnetic field of 0.5 T. The study aims to determine the nature of the dominant transport mechanisms, analyze the transitions between localized and diffuse regimes, and assess the likelihood of quantum transitions in this near-room-temperature thermal range. Electrical measurements revealed non-uniform thermal behavior, indicating the presence of three distinct transport regions. In the lower thermal range (270–285 °K), a localized transport regime characterized by high resistivity, low carrier density, and low mobility prevailed, consistent with variable-range hopping (VRH) mechanisms and weak localization effects resulting from structural defects and surface states. In the intermediate range (285–305 °K), a clear thermal transition was observed, characterized by a sharp decrease in resistivity and a nonlinear change in conductivity, accompanied by a possible reversal in the Hall effect. This behavior suggests a redistribution of electron density with increasing thermal activation of the carriers. In the higher thermal range (305–345 °K), transport became primarily limited by phonon scattering. Conductivity stabilized relatively, and mobility gradually decreased with increasing temperature, while the Hall effect approached zero due to the increasing compensation between the carriers.. These results confirm that the observed behavior reflects a gradual thermal transition between different transport regimes, governed by competition between quantum localization, thermal activation, and phonon scattering.
Keywords: Molybdenum disulfide (MoS₂), Nanostructures, Hall effect, Quantum transport, Thermally activated carrier, Charge carrier mobility, Magnetic transport
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