Small Systems Laboratory, Department of Mechanical Engineering, Worcester Polytechnic Institute, Worcester, Massachusetts 01609, United States of America.
Nanotechnology. 2020 Oct 9;31(41):415707. doi: 10.1088/1361-6528/ab9da9. Epub 2020 Jun 17.
In this study, single-wall carbon nanotubes (SWCNTs) decorated by platinum-group transition metals (Pt, Pd, Rh, or Ru) were introduced as promising nanosensors for the detection of toluene, an important biomarker in the exhaled breath of the lung cancer patients. First-principle calculations based on density functional theory (DFT) was employed to scrutinize the impact of an individual toluene gas molecule on the structural, electronic, and magnetic properties of pristine and metal decorated SWCNTs. It was discovered that toluene is physisorbed on the pristine SWCNT through the interaction of the π orbitals of the carbon atoms in the toluene and the nanotube. Decoration of the SWCNT with metal atoms enhanced the adsorption energies significantly by means of strong overlapping between d orbital of the metal atoms and p orbital of C atoms in the benzene ring of toluene. Investigations showed that toluene is strongly chemisorbed on Rh- and Ru-SWCNT systems via strong covalent bonds with the superior response (-96.98% and -99.98%, respectively), and moderately chemisorbed on Pt-SWCNTs (-27.3%) and Pd-SWCNTs (61.60%). Our findings propose metal decorated SWCNT molecular sensors are attractive candidates for the detection of toluene and other lung cancer biomarkers in the exhaled breath of the lung cancer patients.
在这项研究中，引入了由铂族过渡金属（Pt、Pd、Rh 或 Ru）修饰的单壁碳纳米管（SWCNT）作为探测甲苯的有前途的纳米传感器，甲苯是肺癌患者呼气中重要的生物标志物。基于密度泛函理论（DFT）的第一性原理计算被用来仔细研究单个甲苯气体分子对原始和金属修饰的 SWCNT 的结构、电子和磁性性质的影响。研究发现，甲苯通过甲苯中碳原子的π轨道与纳米管之间的相互作用，通过物理吸附在原始 SWCNT 上。金属原子对 SWCNT 的修饰通过金属原子的 d 轨道和甲苯苯环中 C 原子的 p 轨道之间的强烈重叠，显著增强了吸附能。研究表明，甲苯通过与 Rh-和 Ru-SWCNT 系统的强共价键强烈化学吸附（分别为-96.98%和-99.98%），并适度化学吸附在 Pt-SWCNTs（-27.3%）和 Pd-SWCNTs（61.60%）上。我们的研究结果表明，金属修饰的 SWCNT 分子传感器是探测肺癌患者呼气中甲苯和其他肺癌生物标志物的有吸引力的候选物。
