Applied Physics
Mohammed A. Ibrahem; Emanuele Verrelli; Khue T. Lai; Fei Cheng; Mary O’Neill
Abstract
ZnO nanoparticles have gained considerable interest lately due to their remarkable optical and electrical properties, which enable them to have the potential to be the next generation of transparent semiconductors. However, interactions with atmospheric water and surface carbonates limited and seriously ...
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ZnO nanoparticles have gained considerable interest lately due to their remarkable optical and electrical properties, which enable them to have the potential to be the next generation of transparent semiconductors. However, interactions with atmospheric water and surface carbonates limited and seriously threatened device stability and dependability. The UV photoconductivity of the ZnO NP films is heavily influenced by oxygen adsorption and organic species in the ambient air. The stability of the ZnO photodetector prepared, annealed, and tested in a nitrogen atmosphere was improved in terms of current magnitude and sustaining photocurrent cycles. ZnO NPs films processed in the air show considerable change in surface composition compared to nitrogen indicated by surface organic complexes. In an oxidized manufacturing environment, the compounds above were effectively eliminated while partly degraded in nitrogen. We find that the ZnO NPs surface is highly reactive with ambient CO2, generating surface carbonates groups that promote electrically active surface states.
Nanotechnology
Abbas A. Thajeel; Mohammed A. Ibrahem; Duha S. Ahmed
Abstract
Nanoplasmonic sensing, based on the plasmonic resonance absorption of thin, irregularly-shaped Au nanostructures film, with a starting thickness of about 15 nm (±3 nm) sputtered on a quartz substrate, is used to monitor the CeO2 NPs (with an average diameter of 50 nm) film refractive index variations ...
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Nanoplasmonic sensing, based on the plasmonic resonance absorption of thin, irregularly-shaped Au nanostructures film, with a starting thickness of about 15 nm (±3 nm) sputtered on a quartz substrate, is used to monitor the CeO2 NPs (with an average diameter of 50 nm) film refractive index variations using different film thicknesses (90 nm, 146 nm, 172 nm, and 196 nm). Increasing the film thickness of solution-processed CeO2 NPs film, with layer-by-layer deposition on top of Au nanostructures, shows a significant redshift in the plasmonic resonance absorption of the plasmonic metal, from 580 nm to 611 nm. Such an increase is related to the change in the building microstructure of the semiconductor’s film which is reflected in changing its refractive index. Plasmonic surface refractive index sensitivity of 437.5 nm/RIU with FOM of 4.2 has been recorded. Such a sensing technique offers a large potential for developing cost-effective plasmonic nanosensing devices for clinical applications. This sensor structure is versatile and can be utilized to sense and monitor a large variety of materials and chemicals.