Effect of CuO introduced on activated carbon fibers formed by electroless plating on the NO gas sensing

To improve the sensitivity of NO gas, ACFs were treated according plating time conditions and used as a NO gas sensor material. [Display omitted] •CuO particles were introduced on ACFs surface via electroless copper plating.•The CuO-ACF electrodes were used as NO gas sensors.•When the plating time is 15min, NO gas sensing and recovery were improved than untreated ACFs.•The introduced CuO acts as a catalyst on ACFs surface to transfer electrons. High-performance gas sensors were fabricated from activated carbon fibers (ACFs) introduced with CuO. The electroless CuO plating of ACFs was carried out to investigate the nitric oxide (NO) gas sensing ability with respect the plating time. The gas sensors were fabricated by dropping a solution (CuO-introduced ACFs+DMF) onto SiO2/Si wafers patterned with Pt electrodes. The NO gas sensing behavior of the ACF-based gas sensors was determined by resistance measurements. As the plating time increased, the CuO content on the ACF surface increased, and the specific surface area of the ACFs decreased. The gas sensor fabricated from untreated ACFs showed a 4% resistance change upon exposure to NO gas, whereas the sensor with CuO-introduced ACFs showed an approximately 12.5% resistance change. This phenomenon is attributed to the increased number of hole carriers in the ACFs due to CuO, which promotes electron transfer, and benefits the effective detection of NO gas. This method provides as a unique surface treatment strategy to improve the NO gas sensing efficiency.