| Abstract [eng] |
This project explores the fabrication and characterisation studies of spray-coated zinc oxide (ZnO) nanotetrapods and their composite material (g-C3N4/ZnO-T) based chemiresistive sensor for enhanced UV and gas sensing performance. It deals with the chemiresistive UV and NO2 sensing performance of the spray-coated zinc oxide nanotetrapods (ZnO-T) and their composite with graphitic carbon nitride (g-C3N4) for NO2 gas detection. We utilise three distinct signal transduction patterns during each phase of the project. ZnO nanotetrapods are utilised due to their outstanding sensing features, which include a unique three-dimensional morphology, more active sites for adsorption of oxygen, an efficient electron transport mechanism, and improved sensitivity to hazardous gases. The fabrication of the sensor consists of the spray-coating and has benefits, including being a cost-effective, scalable, and less energy-dissipating technique. This deposition method is carried out onto the surface of electrodes of variable configurations having different interelectrode gaps. This provides the tuning of sensitivity, optimisation, and the understanding of electron transport properties. The sensing performance was investigated by exposing UV radiation (500 μW/cm2) and 10 ppm NO2 gas to observe the variations of the current over time. The performance parameters of the analysis comprise response time, recovery time, repeatability, responsivity, and stability. These parameter values exhibit variable values for distinct interelectrode gaps. These findings provide essential information about the surface resistance of ZnO nanotetrapods and their composite with melamine-derived graphitic carbon nitride (g-C3N4) and electron transport sensing mechanism. This research offers the exceptional benefits of the spray-coated chemiresistive sensor based on ZnO nanotetrapods, and due to the chemically stable, scalable, low-cost, and versatile nature, it opens new avenues for applications in advanced nanomaterial sensing technology, environmental pollution monitoring, industrial safety, and medical diagnostics. g-C3N4 and ZnO working together allow for faster charge transport, reduce recombination and make the signal stronger than the noise during operation of the sensor. Because the ZnO nanotetrapods do not break easily, they are highly stable and suitable for real-world use. By using a range of electrode gap sizes, scientists can learn how the microstructure and field distribution affect the material’s response. Besides, using advanced, cost-effective fabrication techniques like spray-coating allows the platform to become small and easily combined with suitable substrate for portable sensor devices. The results hint at the possibility of detecting other target gases by adjusting the surface of the sensor, strengthening future efforts in building multi-gas detectors and smart sensing networks. |
