Moon, Hi Gyu Choi, You Rim Shim, Young-Seok Choi, Kwon-Il Lee, Jong-Heun Kim, Jin-Sang Yoon, Seok-Jin Park, Hyung-Ho Kang, Chong-Yun Jang, Ho Won 2024-01-20T11:03:15Z 2024-01-20T11:03:15Z 2021-09-04 2013-11-13 1944-8244 https://pubs.kist.re.kr/handle/201004/127443 Self-assembled WO3 thin film nanostructures with 1-dimensional villi-like nanofingers (VLNF) have been synthesized on the SiO2/Si substrate with Pt interdigitated electrodes using glancing angle deposition (GAD). Room-temperature deposition of WO3 by GAD resulted in anisotropic nanostructures with large aspect ratio and porosity having a relative surface area, which is about 32 times larger than that of a plain WO3 film. A WO3 VLNF sensor shows extremely high response to nitric oxide (NO) at 200 degrees C in Time (s) 80% of relative humidity atmosphere, while responses of the sensor to ethanol, acetone, ammonia, and carbon monoxide are negligible. Such high sensitivity and selectivity to NO are attributed to the highly efficient modualtion of potential barriers at narrow necks between individual WO3 VLNF and the intrinsically high sensitivity of WO3 to NO. The theoretical detection limit of the sensor for NO is expected to be as low as 88 parts per trillion (ppt). Since NO is an approved biomarker of chronic airway inflammation in asthma, unprecedentedly high response and selectivity, and ppt-level detection limit to NO under highly humid environment demonstrate the great potential of the WO3 VLNF for use in high performance breath analyzers. English American Chemical Society NITRIC-OXIDE GAS SENSOR SENSING PROPERTIES NANOPARTICLES FABRICATION ASTHMA SNO2 ZNO NANOWIRES DIAGNOSIS Extremely Sensitive and Selective NO Probe Based on Villi-like WO3 Nanostructures for Application to Exhaled Breath Analyzers Article 10.1021/am402456s 1 ACS Applied Materials & Interfaces, v.5, no.21, pp.10591 - 10596 ACS Applied Materials & Interfaces 5 21 10591 10596 scie scopus 000327103500026 2-s2.0-84887591994 Nanoscience & Nanotechnology Materials Science, Multidisciplinary Science & Technology - Other Topics Materials Science Article NITRIC-OXIDE GAS SENSOR SENSING PROPERTIES NANOPARTICLES FABRICATION ASTHMA SNO2 ZNO NANOWIRES DIAGNOSIS semiconducting metal oxide gas sensor WO3 nanostructures glancing angle deposition NO probe exhaled breath analyzer