{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T11:54:48Z","timestamp":1768823688956,"version":"3.49.0"},"reference-count":52,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2021,8,27]],"date-time":"2021-08-27T00:00:00Z","timestamp":1630022400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Science and Technology (MOST) and the Bureau of Energy, Ministry of Economic Affairs, Taiwan","award":["108-2221-E-007-002, 110-2221-E-A49-146, and 110-E2011."],"award-info":[{"award-number":["108-2221-E-007-002, 110-2221-E-A49-146, and 110-E2011."]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this research work, the gas sensing properties of halogenated chloroaluminum phthalocyanine (ClAlPc) thin films were studied at room temperature. We fabricated an air-stable ClAlPc gas sensor based on a vertical organic diode (VOD) with a porous top electrode by the solution process method. The surface morphology of the solution-processed ClAlPc thin film was examined by field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM). The proposed ClAlPc-based VOD sensor can detect ammonia (NH3) gas at the ppb level (100~1000 ppb) at room temperature. Additionally, the ClAlPc sensor was highly selective towards NH3 gas compared to other interfering gases (NO2, ACE, NO, H2S, and CO). In addition, the device lifetime was tested by storing the device at ambient conditions. The effect of relative humidity (RH) on the ClAlPc NH3 gas sensor was also explored. The aim of this study is to extend these findings on halogenated phthalocyanine-based materials to practical electronic nose applications in the future.<\/jats:p>","DOI":"10.3390\/s21175783","type":"journal-article","created":{"date-parts":[[2021,8,31]],"date-time":"2021-08-31T22:58:15Z","timestamp":1630450695000},"page":"5783","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Solution-Processed Chloroaluminum Phthalocyanine (ClAlPc) Ammonia Gas Sensor with Vertical Organic Porous Diodes"],"prefix":"10.3390","volume":"21","author":[{"given":"Govindsamy","family":"Madhaiyan","sequence":"first","affiliation":[{"name":"Institute of Physics, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan"}]},{"given":"An-Ting","family":"Sun","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, National Tsing Hua University, Hsinchu 30010, Taiwan"}]},{"given":"Hsiao-Wen","family":"Zan","sequence":"additional","affiliation":[{"name":"Department of Photonics, Institute of Electro-Optical Engineering, College of Electrical and Computer, Engineering, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan"}]},{"given":"Hsin-Fei","family":"Meng","sequence":"additional","affiliation":[{"name":"Institute of Physics, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan"}]},{"given":"Sheng-Fu","family":"Horng","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, National Tsing Hua University, Hsinchu 30010, Taiwan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5607-1428","authenticated-orcid":false,"given":"Li-Yin","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Photonics, Institute of Electro-Optical Engineering, College of Electrical and Computer, Engineering, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan"}]},{"given":"Hsiao-Wen","family":"Hung","sequence":"additional","affiliation":[{"name":"Intelligent Energy-Saving Systems Division, Green Energy and Environment Research Laboratories, Industrial Technology Research Institute, Hsinchu 30010, Taiwan"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.tifs.2020.02.028","article-title":"Principles and recent advances in electronic nose for quality inspection of agricultural and food products","volume":"99","author":"Ali","year":"2020","journal-title":"Trends Food Sci. 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