In:
International Journal of Modern Physics B, World Scientific Pub Co Pte Ltd, Vol. 33, No. 16 ( 2019-06-30), p. 1950166-
Abstract:
The effect of gas molecule (H 2 CO, NO, NO 2 , O 2 and SO 2 ) adsorption on the electronic and magnetic properties of Mn-doped graphene (MnG) is investigated by first-principles calculations in the framework of density functional theory (DFT). Our study reveals that after H 2 CO, NO, NO 2 and SO 2 adsorption, MnG transforms from half-metal to semiconductor, and this transformation indicates that MnG’s conductivity is changed significantly. Meanwhile, O 2 adsorption has no influence on MnG’s original electronic property. Therefore, the substrate of MnG is highly sensitive to H 2 CO, NO, NO 2 and SO 2 . The reconfiguration of electron distribution caused by gas adsorption dramatically alters the spin polarization distribution of the combined system, that is, NO 2 and H 2 CO adsorption leads to local spin polarization, whereas O 2 , NO and SO 2 adsorption result in complete spin polarization. In addition, the external electric field (E-field) is varied from −0.50 V/Å to +0.50 V/Å then applied to the adsorption system. A strong interaction is observed between gas and MnG with a positive E-field as reflected in the enhancement of adsorption energy. The interaction is obviously weakened by introducing the E-field in the negative direction. Hence, the adsorption strength and sensitivity of gas on MnG can be effectively tuned by the E-field. The results can serve as useful references for the design of graphene-based gas sensor.
Type of Medium:
Online Resource
ISSN:
0217-9792
,
1793-6578
DOI:
10.1142/S0217979219501662
Language:
English
Publisher:
World Scientific Pub Co Pte Ltd
Publication Date:
2019
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