Gas sensing with Au-decorated carbon nanotubes.
Gas sensing with Au-decorated carbon nanotubes.
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DOI：
10.1021/nn200294h
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发表时间：
2011-05
期刊：
影响因子：
17.1
通讯作者：
Z. Zanolli;R. Leghrib;A. Felten;J. Pireaux;E. Llobet;J. Charlier
中科院分区：
文献类型：
--
作者：
Z. Zanolli;R. Leghrib;A. Felten;J. Pireaux;E. Llobet;J. Charlier
通过理论和实验相结合的方法研究了金纳米粒子修饰的碳纳米管（CNT）的传感特性。一方面，第一原理和非平衡格林函数技术可以了解单个纳米管中传感机制的微观特征，例如电子电荷转移和量子电导。另一方面，用金纳米颗粒装饰的碳纳米管在传感器基底上的滴涂沉积及其在检测NO(2)、CO和C(6)H(6)等污染物中的表征提供了对纳米管垫传感能力的深入了解。使用目前的组合方法，解释了使用金功能化纳米管检测某些特定气体（NO(2) 和 CO）的改进。然而，对于 C(6)H(6) 等其他气体，与用氧等离子体功能化的原始 CNT 相比，Au 纳米颗粒似乎在传感过程中并未发挥关键作用。事实上，这些不同的情况可以通过识别气体吸附后电阻的变化（宏观特征）和费米能级的变化（微观特征）之间的关系来解释。对原子水平传感能力的理解开辟了设计新气体传感器并通过预测最适合检测特定分子种类的金属性质来调整其选择性的方法。
The sensing properties of carbon nanotubes (CNTs) decorated with gold nanoparticles have been investigated by means of combined theoretical and experimental approaches. On one hand, first-principles and nonequilibrium Green's functions techniques give access to the microscopic features of the sensing mechanisms in individual nanotubes, such as electronic charge transfers and quantum conductances. On the other hand, drop coating deposition of carbon nanotubes decorated with gold nanoparticles onto sensor substrates and their characterization in the detection of pollutants such as NO(2), CO, and C(6)H(6) provide insight into the sensing ability of nanotube mats. Using the present combined approaches, the improvement in the detection of some specific gases (NO(2) and CO) using Au-functionalized nanotubes is explained. However, for other gases such as C(6)H(6), the Au nanoparticles do not seem to play a crucial role in the sensing process when compared with pristine CNTs functionalized with oxygen plasma. Indeed, these different situations can be explained by identifying the relationship between the change of resistance (macroscopic feature) and the shift of the Fermi level (microscopic feature) after gas adsorption. The understanding of the sensing ability at the atomic level opens the way to design new gas sensors and to tune their selectivity by predicting the nature of the metal that is the most appropriate to detect specific molecular species.