Probing the role of CNTs in Pt nanoparticle/CNT/graphene nanohybrids H₂ sensors

Abstract

In the carbon nanotubes film/graphene heterostructure decorated with catalytic Pt nanoparticles using atomic layer deposition (Pt-NPs/CNTs/Gr) H2 sensors, the CNT film determines the effective sensing area and the signal transport to Gr channel. The former requires a large CNT aspect ratio for a higher sensing area while the latter demands high electric conductivity for efficient charge transport. Considering the CNT’s aspect ratio decreases, while its conductivity increases (i.e., bandgap decreases), with the CNT diameter, it is important to understand how quantitatively these effects impact the performance of the Pt-NPs/CNTs/Gr nanohybrids sensors. Motivated by this, this work presents a systematic study of the Pt-NPs/CNTs/Gr H2 sensor performance with the CNT films made from different constituent CNTs of diameters ranging from 1 nm for single-wall CNTs, to 2 nm for double-wall CNTs, and to 10-30 nm for multi-wall CNTs (MWCNTs). By measuring the morphology and electric conductivity of SWCNT, DWCNT and MWCNT films, this work aims to reveal the quantitative correlation between the sensor performance and relevant CNT properties. Interestingly, the best performance is obtained on Pt-NPs/MWCNTs/Gr H2 sensors, which can be attributed to the compromise of the effective sensing area and electric conductivity on MWCNT films and illustrates the importance of optimizing sensor design.

Ab Initio Study of Optical Properties of Hybrid Films Based on Bilayer Graphene and Single-Walled Carbon Nanotubes

“…This sensor showed high sensitivity (gauge factor ~197 at 10% strain) and extensibility (able to be stretched up to 50%), as well as a reproducible response during 1000 loading cycles, including stretching and bending. Among recent applied developments based on graphene-nanotube hybrids, photodetectors and sensors should be noted [20][21][22][23]. Zhang et al proposed a simple and feasible method for creating a highly sensitive broadband photodetector based on graphene-nanotube heterojunction [20].…”

“…The fabricated photodetector demonstrated a high photosensitivity of 10 9 A/W and a fast photoresponse rate of 2.9 ms in the visible region, as well as photosensitivity of 51.5 A/W at 940 nm. Alamri et al proposed an H 2 sensor based on a graphene/SWCNTs heterostructure decorated with catalytic Pt nanoparticles [22]. In the proposed design of the device, the SWCNT film determines the effective sensing area and signal transport to the graphene channel.…”