The use of hybrid nanostructures is of great interest to take advantage of their constructing components. However, the reason for the improved features of these structures has not yet been fully explained and there are some ambiguities. So we studied and compared sensing properties of carbon nanotube (CNT) and CNT decorated with zinc oxide (ZnO) nanoparticle (CNT/ZnO). Studied target gas molecules were CH ₄ , CO, H ₂ S and NO ₂ . Different performance of CNT and CNT/ZnO structures were defined by calculating their density of sates before and after gas adsorption. The adsorption energy of molecules on both structures and charge transfer between molecules and their surfaces were also estimated using density functional theory (DFT) method. Compared to the pristine CNT, electrical properties of CNT/ZnO is influenced more notably according to the gas adsorption as the molecules have higher adsorption energy and larger charge transfer with the structure. Thus, the band gap of CNT/ZnO is also more affected by gas adsorption. The relation between band gap variations and the gas response of the structures was modeled and showed that the greater the band gap changes due to a gas adsorption, the better the structure gas sensing responses to it. Therefore, it can be concluded that the ZnO decorated CNT shows better gas sensing properties.

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碳纳米管和氧化锌修饰的碳纳米管的气敏特性建模与比较

利用杂化纳米结构以利用它们的构造成分引起了极大的兴趣。但是，这些结构的改进特征的原因尚未完全解释，并且存在一些歧义。因此，我们研究并比较了碳纳米管（CNT）和装饰有氧化锌（ZnO）纳米颗粒（CNT / ZnO）的CNT的传感特性。研究的目标气体分子为CH ₄ ，CO，H ₂ S和NO ₂ 。CNT和CNT / ZnO结构通过计算气体吸附前后的态密度来定义不同的性能。还使用密度泛函理论（DFT）方法估算了分子在结构上的吸附能以及分子与表面之间的电荷转移。与原始CNT相比，由于分子具有更高的吸附能和更大的电荷转移结构，因此CNT / ZnO的电学性能受气体吸附的影响更大。因此，CNT / ZnO的带隙也更受气体吸附的影响。对带隙变化与结构的气体响应之间的关系进行了建模，结果表明，由于气体吸附，带隙变化越大，结构对它的气敏响应越好。所以，