Effect of vacancy defect and dopants on the sensitivity of germanene to H2CO

• Published in: Physica. E, Low-dimensional systems & nanostructures Vol. 142; p. 115268
• Main Authors: Wang, Hui, Zhou, Qingxiao, Ju, Weiwei, Sun, Wenjun
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.08.2022
• ISSN: 1386-9477; 1873-1759
• DOI: 10.1016/j.physe.2022.115268

The geometric and electronic structures, magnetism, and recovery time of vacancy-defected and doped germanene, which is used as a sensor for the detection of H2CO molecule, are examined using first-principles calculation methods. The results reveal that the introduction of vacancy and transition metal dopants (V, Cr, Mn, Fe) increases the adsorption stability of H2CO on germanene. In addition, V-doped vacancy-defected germanene (V-VGe) is converted from semiconductor to conductor by absorbing H2CO molecules, which can be used as an obvious signal to detect H2CO gas. Furthermore, the strong interaction with H2CO and the short recovery time indicates that V-VGe is most sensitive to the H2CO molecules. Overall, the findings of this study provide theoretical reference for the design of a new H2CO gas sensor. First-principles calculation method based on density functional theory is used to study the effect of vacancy and transition metal dopants (V, Cr, Mn, Fe) on the adsorption of H2CO on germanene.The results show that doping effectively improves the sensitivity of the vacancy-defected germanene to H2CO molecule. [Display omitted] •The appearance of vacancy defects enhances the sensitivity of the germanene substrate.•Doped transition metal atoms (V, Cr, Mn, Fe) can improve the adsorption capacity of vacancy-defective germanene to H2CO molecules.•Vacancy-defective germanene doped with V atoms can be used to detect H2CO molecules.