MBenes analogous to MXenes, exfoliated from the bulk MAB phase (M = transition metal, A = IIIA and IVA group, and B = boron) have appeared as promising two dimensional (2D) materials due to their intriguing properties. Here, we report the 2D 1T-2H-phase of Mo2B with their functionalized derivatives Mo2BX2 (X= H, OH, O) and investigate their structural, electronic, and adsorption behavior of toxic gases using the first-principles calculations. This study finds that pristine and functionalized MBenes have dynamic and thermal stability and possess metallic nature in both phases. Based on adsorption behavior and comparison with other 2D materials, we find that pristine MBenes are a desirable adsorbent for NO2, SO2, and CO2 capture. In contrast, the moderate adsorption energies for functionalized MBenes-NH3 systems reveal good sensitivity for NH3 gas detection in both phases. In particular, 2H-Mo2BH2 has higher CT (-0.11e) and appropriate adsorption energy (-0.30 eV), leads a shorter recovery time. Further, DOS calculations reveal that the electrical conducting behavior of MBenes makes them suitable for NH3 detection with a short recovery time. Our results would provide the first insight into the surface-functionalized effect on the structural and electronic properties of the MBenes, and shed light on the application of MBenes for the sensing and catalyst of typical toxic and greenhouse gases, respectively.

Foreign