Abstract
This work from first-principles insight uses a MoS(2)-WS(2) in-plane heterostructure as a potential sensing material for detection of CO and C(2)H(2), two typical dissolved gases in oil-immersed transformers, in order to evaluate the operation status. The adsorption performance of the MoS(2)-WS(2) heterostructure upon two gas species is assessed via three adsorption sites and compared with isolated MoS(2) and WS(2). Results indicate that MoS(2)-WS(2) performs with a much stronger binding force and charge-transfer for adsorptions of CO and C(2)H(2) in comparison to the isolated counterpart, which gives rise to more obvious deformation in the electronic property of MoS(2)-WS(2) as well as a much larger resistance-based sensing response. The recovery time of MoS(2)-WS(2) for desorption of CO and C(2)H(2) molecules is also appropriate to allow the reusability of such a sensor. The findings in this work uncover the admirable sensing potential of transition metal dichalcogenides (TMDs)-based heterostructures upon oil dissolved gases, which opens up a new way to explore novel 2D nanomaterials as resistive gas sensors for dissolved gas analysis in electrical oil-immersed transformers.