Non-modified (ZnO) and modified (Fe2O3@ZnO and CuO@ZnO) structured films are deposited via aerosol assisted chemical vapor deposition. The surface modification of ZnO with iron or copper oxides is achieved in a second aerosol assisted chemical vapor deposition step and the characterization of morphology, structure, and surface of these new structured films is discussed. X-ray photoelectron spectrometry and X-ray diffraction corroborate the formation of ZnO, Fe2O3, and CuO and the electron microscopy images show the morphological and crystalline characteristics of these structured films. Static water contact angle measurements for these structured films indicate hydrophobic behavior with the modified structures showing higher contact angles compared to the non-modified films. Overall, results show that the modification of ZnO with iron or copper oxides enhances the hydrophobic behavior of the surface, increasing the contact angle of the water drops at the non-modified ZnO structures from 122 to 135 and 145 for Fe2O3@ZnO and CuO@ZnO, respectively. This is attributed to the different surface properties of the films including the morphology and chemical composition.

• Keywords
• AACVD, copper oxide, iron oxide, structured films, water contact angle, zinc oxide,
• Publication type
• Journal Article MeSH

Gas sensitive cerium oxide-tungsten oxide core-shell nanowires are synthesized and integrated directly into micromachined platforms via aerosol assisted chemical vapor deposition. Tests to various volatile organic compounds (acetone, ethanol, and toluene) involved in early disease diagnosis demonstrate enhanced sensitivity to acetone for the core-shell structures in contrast to the non-modified materials (i.e., only tungsten oxide or cerium oxide). This is attributed to the high density of oxygen vacancy defects at the shell, as well as the formation of heterojunctions at the core-shell interface, which provide the modified nanowires with 'extra' chemical and electronic sensitization as compared to the non-modified materials.

• Keywords
• acetone, gas sensors, heterojunctions, metal oxides, volatile organic compounds (VOCs),
• MeSH
• Acetone metabolism   MeSH
• Cerium chemistry   MeSH
• Nanowires chemistry   MeSH
• Oxides chemistry   MeSH
• Volatile Organic Compounds metabolism   MeSH
• Tungsten chemistry   MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Acetone MeSH
• Cerium MeSH
• ceric oxide MeSH Browser
• Oxides MeSH
• Volatile Organic Compounds MeSH
• tungsten oxide MeSH Browser
• Tungsten MeSH