Background: Formaldehyde (HCOH) is the most abundant airborne carbonyl indoor volatile organic compound (VOC), which is well-known to cause serious health effects such as respiratory system disease, immune system disorders, and central nervous system damage.

Methods: The interaction between HCOH and intrinsic, congeners of Au, Ag, Cu-doped SWCNTs were investigated by density functional theory (DFT) to evaluate the detection of formaldehyde.

Results: The results demonstrated that the less adsorption on the surface of intrinsic SWCNT, an HCOH molecule tended to be chemisorbed to the Au, Ag, and Cu atoms of doped SWCNT with larger binding energy of 0.4-0.8 eV and smaller binding distance of 1.9-2.3 Å. Furthermore, charge transfer and density of state studies indicated tha t the electronic properties changed evidently in the most stable HCOH-doped SWCNT systems, mainly at the region of -5.5 to -4.5 eV and Fermi level.

Conclusion: More importantly, the adsorption of HCOH affected the electronic conductance of doped SWCNT. It is expected that the results obtained in this study could provide a useful theoretical guidance for the investigation of molecular films interface bonding and design of HCOH sensing devices.

背景：甲醛（HCOH）是空气中羰基含量最高的室内挥发性有机化合物（VOC），众所周知，甲醛会引起严重的健康影响，例如呼吸系统疾病，免疫系统疾病和中枢神经系统损害。

方法：采用密度泛函理论（DFT）研究了HCOH与金，银，铜掺杂的单质碳纳米管之间的相互作用，以评价甲醛的检测。

结果：结果表明，固有SWCNT表面的吸附较少，HCOH分子倾向于化学吸附到掺杂SWCNT的Au，Ag和Cu原子上，结合能较大，为0.4-0.8 eV，结合距离较小，为1.9 -2.3Å。此外，电荷转移和状态密度研究表明，在最稳定的HCOH掺杂SWCNT系统中，电子性能发生了明显变化，主要在-5.5至-4.5 eV和费米能级范围内。

结论：更重要的是，HCOH的吸附会影响掺杂的SWCNT的电子电导。可以预期，这项研究中获得的结果将为研究分子膜界面键合和HCOH传感设备的设计提供有用的理论指导。