Our work has reflected considerable interest in unique Pd nanocluster/MoS2 heterojunction systems due to their potential applications in materials science, chemistry and physics. We focused on exploiting Pd5/MoS2 nanocluster system, a novel heterojunction material for gas sensing applications. In addition, we exploited the electronic properties of Pd dopant on the MoS2 surface to make a comparative study. Our DFT calculations indicate that the Pd5/MoS2 heterojunction structure exhibits a higher affinity for adsorbing gas molecules such as CO, NH3, NO, and NO2, while the perfect MoS2 shows weak gas adsorption capacity. Pd5/MoS2 heterojunction exhibits semiconducting feature with a weakened and narrower band gap, making it more suitable for gas sensing due to its higher conductivity. We analyzed important factors like adsorption distance/energies, density of states, band structure and difference of electron density concerning adsorbed gases on the heterojunction surface. Based on the electron density difference maps, we can see the giant growth of charges over the adsorbed molecules, as well as between the adsorbing atoms. Based on our findings, the conductivity of the nanomaterial undergoes a remarkable change, which helps reinforce the applicability of the Pd5/MoS2 heterojunction nanosystem in sensing and adsorbing gas molecules.
Read full abstract