Nano Research

Article Title

Highly sensitive hybrid nanofiber-based room-temperature CO sensors: Experiments and density functional theory simulations


hybrid nanofiber, high active facet, gas sensor, selectivity, highly sensitive, density functional theory


ABSTRACT Chemical sensors (CSs) are an emerging area in nanoscience research, which focuses on the highly sensitive detection of toxic and hazardous gases and diseaserelated volatile organics. While the field has advanced rapidly in recent years, it lacks the theoretical support required for the rational design of innovative materials with tunable measurement responses. Herein, we present a one-dimensional (1D) hybrid nanofiber decorated with ultrafine NiO nanoparticles (NiO NPs) as an efficient active component for CSs. Highly dispersed (110)-facet NiO NPs with a high percentage of Ni2+ active sites with unsaturated coordination were confined in a TiO2 nanofiber (TiO2 NF) matrix that is favorable for surface catalytic reactions. The CSs constructed using the 1D heterostructure NiO/TiO2 nanofibers (NiO/TiO2 HNFs) exhibited a highly selective response to trace CO gas molecules (1 ppm) with high sensitivity (ᇞR/R0 = 1.02), ultrafast response/ recovery time (Tres/Trecov < 20 s), and remarkable reproducibility at room temperature. The density functional theory (DFT) simulations and experimental results confirmed that the selective response could be attributed to the high molecular adsorption energy of the NiO nanoparticles with (110) facets and abundant interfaces, which act synergistically to promote CO adsorption and facilitate charge transfer.

Graphical Abstract


Tsinghua University Press