{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,18]],"date-time":"2026-01-18T00:20:51Z","timestamp":1768695651007,"version":"3.49.0"},"reference-count":25,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2020,2,26]],"date-time":"2020-02-26T00:00:00Z","timestamp":1582675200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2016YFC0303900"],"award-info":[{"award-number":["2016YFC0303900"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2017YFC0209700"],"award-info":[{"award-number":["2017YFC0209700"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["No. 41475023"],"award-info":[{"award-number":["No. 41475023"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["No. 41730103"],"award-info":[{"award-number":["No. 41730103"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["No. 41575030"],"award-info":[{"award-number":["No. 41575030"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A fully integrated photoacoustic nitrogen dioxide (NO2) sensor is developed and demonstrated. In this sensor, an embedded photoacoustic cell was manufactured by using an up-to-date 3D printing technique. A blue laser diode was used as a light source for excitation of photoacoustic wave in the photoacoustic cell. The photoacoustic wave is detected by a sensitive microelectromechanical system (MEMS) microphone. Homemade circuits are integrated into the sensor for laser diode driving and signal processing. The sensor was calibrated by using a chemiluminescence NO\u2013NO2\u2013NOX gas analyzer. And the performance of this sensor was evaluated. The linear relationship between photoacoustic signals and NO2 concentrations was verified in a range of below 202 ppb. The limit of detection was determined to 0.86 ppb with an integration time of 1 s. The corresponding normalized noise equivalent absorption was 2.0 \u00d7 10\u22128 cm\u22121\u2219W\u2219Hz\u22121\/2. The stability and the optimal integration time were evaluated with an Allan deviation analysis, from which a detection limit of 0.25 ppb at the optimal integration time of 240 s was obtained. The sensor was used to measure outdoor air and the results agree with that obtained from the NO\u2013NO2\u2013NOX gas analyzer. The low-cost and portable photoacoustic NO2 sensor has a potential application for atmospheric NO2 monitoring.<\/jats:p>","DOI":"10.3390\/s20051270","type":"journal-article","created":{"date-parts":[[2020,2,27]],"date-time":"2020-02-27T03:21:16Z","timestamp":1582773676000},"page":"1270","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Fully Integrated Photoacoustic NO2 Sensor for Sub-ppb Level Measurement"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9215-1732","authenticated-orcid":false,"given":"Yang","family":"Dong","sequence":"first","affiliation":[{"name":"Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China"},{"name":"Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, China"}]},{"given":"Mingsi","family":"Gu","sequence":"additional","affiliation":[{"name":"Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China"},{"name":"Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, China"}]},{"given":"Gongdong","family":"Zhu","sequence":"additional","affiliation":[{"name":"Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China"}]},{"given":"Tu","family":"Tan","sequence":"additional","affiliation":[{"name":"Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5813-5093","authenticated-orcid":false,"given":"Kun","family":"Liu","sequence":"additional","affiliation":[{"name":"Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China"}]},{"given":"Xiaoming","family":"Gao","sequence":"additional","affiliation":[{"name":"Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China"}]}],"member":"1968","published-online":{"date-parts":[[2020,2,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2063","DOI":"10.1016\/S1352-2310(99)00460-4","article-title":"Atmospheric chemistry of VOCs and NOx","volume":"34","author":"Atkinson","year":"2000","journal-title":"Atmos. Environ."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Zhu, Y., Kuhlmann, G., Chan, K.L., Donner, S., Sch\u00fctt, A., Wagner, T., and Wenig, M. (2016, January 14\u201317). Citywide Measurements of NO2 Concentrations in Munich Using a Combination of Mobile and Stationary Spectroscopic Measurement Techniques. Proceedings of the Light, Energy and the Environment, Leipzig, Germany.","DOI":"10.1364\/HISE.2016.HM4E.4"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"6078","DOI":"10.1021\/es049701c","article-title":"NO and NO2 Emission Ratios Measured from In-Use Commercial Aircraft during Taxi and Takeoff","volume":"38","author":"Herndon","year":"2004","journal-title":"Environ. Sci. Technol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"715","DOI":"10.1021\/acs.jpca.8b08812","article-title":"Mechanism of the Chemiluminescent Reaction between Nitric Oxide and Ozone","volume":"123","author":"Gudem","year":"2019","journal-title":"J. Phys. Chem. A"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"3539","DOI":"10.1016\/j.ceramint.2012.10.178","article-title":"Enhanced NO2 sensing properties of Zn2SnO4-core\/ZnO-shell nanorod sensors","volume":"39","author":"Park","year":"2013","journal-title":"Ceram. Int."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1612","DOI":"10.1021\/acssensors.7b00463","article-title":"Highly Specific and Wide Range NO2 Sensor with Color Readout","volume":"2","author":"Monereo","year":"2017","journal-title":"ACS Sens."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"7831","DOI":"10.1021\/es902067h","article-title":"A Sensitive and Versatile Detector for Atmospheric NO2 and NOX Based on Blue Diode Laser Cavity Ring-Down Spectroscopy","volume":"43","author":"Fuchs","year":"2009","journal-title":"Environ. Sci. Technol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"4906","DOI":"10.1364\/AO.49.004906","article-title":"High sensitivity detection of NO2 employing cavity ringdown spectroscopy and an external cavity continuously tunable quantum cascade laser","volume":"49","author":"Rao","year":"2010","journal-title":"Appl. Opt. AO"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"4531","DOI":"10.5194\/amt-11-4531-2018","article-title":"Development of an incoherent broadband cavity-enhanced absorption spectrometer for in situ measurements of HONO and NO2","volume":"11","author":"Duan","year":"2018","journal-title":"Atmos. Meas. Tech."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"ACH-4","DOI":"10.1029\/2001JD000779","article-title":"A thermal dissociation laser-induced fluorescence instrument for in situ detection of NO2, peroxy nitrates, alkyl nitrates, and HNO3","volume":"107","author":"Day","year":"2002","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1512","DOI":"10.1364\/OE.23.001512","article-title":"Simultaneous measurement of NO and NO2 by dual-wavelength quantum cascade laser spectroscopy","volume":"23","author":"Jouy","year":"2015","journal-title":"Opt. Express OE"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"4046","DOI":"10.1364\/AO.35.004046","article-title":"Detection of NO and NO2 by (2 + 2) resonance-enhanced multiphoton ionization and photoacoustic spectroscopy near 454 nm","volume":"35","author":"Pastel","year":"1996","journal-title":"Appl. Opt. AO"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"751","DOI":"10.1007\/s003400100686","article-title":"High-precision pulsed photoacoustic spectroscopy in NO2-N2","volume":"73","author":"Slezak","year":"2001","journal-title":"Appl. Phys. B"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1016\/S0143-8166(02)00062-3","article-title":"Photoacoustic detection of NO2 traces with CW and pulsed green lasers","volume":"40","author":"Slezak","year":"2003","journal-title":"Opt. Lasers Eng."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"10846","DOI":"10.1073\/pnas.0604238103","article-title":"Sub-parts-per-billion level detection of NO2 using room-temperature quantum cascade lasers","volume":"103","author":"Pushkarsky","year":"2006","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"481","DOI":"10.1364\/OL.36.000481","article-title":"Application of a broadband blue laser diode to trace NO2 detection using off-beam quartz-enhanced photoacoustic spectroscopy","volume":"36","author":"Yi","year":"2011","journal-title":"Opt. Lett. OL"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"2933","DOI":"10.1364\/OL.40.002933","article-title":"Parts-per-trillion-level detection of nitrogen dioxide by cantilever-enhanced photo-acoustic spectroscopy","volume":"40","author":"Peltola","year":"2015","journal-title":"Opt. Lett. OL"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"329","DOI":"10.1016\/j.snb.2017.03.058","article-title":"Sub-ppb nitrogen dioxide detection with a large linear dynamic range by use of a differential photoacoustic cell and a 3.5W blue multimode diode laser","volume":"247","author":"Yin","year":"2017","journal-title":"Sens. Actuators B Chem."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"501","DOI":"10.1016\/j.sna.2017.06.036","article-title":"Low-cost photoacoustic NO2 trace gas monitoring at the pptV-level","volume":"263","author":"Bierl","year":"2017","journal-title":"Sens. Actuators A Phys."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Kapp, J., Weber, C., Schmitt, K., Pernau, H.-F., and W\u00f6llenstein, J. (2019). Resonant Photoacoustic Spectroscopy of NO2 with a UV-LED Based Sensor. Sensors, 19.","DOI":"10.3390\/s19030724"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"171","DOI":"10.1016\/S0022-4073(97)00168-4","article-title":"Measurements of the NO2 absorption cross-section from 42 000 cm\u22121 to 10 000 cm\u22121 (238\u20131000 nm) at 220 K and 294 K","volume":"59","author":"Vandaele","year":"1998","journal-title":"J. Quant. Spectrosc. Radiat. Transf."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"157","DOI":"10.1016\/j.micpro.2003.12.002","article-title":"Digital lock in amplifier: Study, design and development with a digital signal processor","volume":"28","author":"Gaspar","year":"2004","journal-title":"Microprocess. Microsyst."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Chighine, A., Tsekenis, S.-A., Fisher, E., Polydorides, N., Wilson, D., Lengden, M., Johnstone, W., and McCann, H. (2015, January 1\u20134). TDLAS using FPGA-based lock-in detection for multi-channel Chemical Species Tomography. Proceedings of the 2015 IEEE SENSORS, Busan, Korea.","DOI":"10.1109\/ICSENS.2015.7370677"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"075103","DOI":"10.1063\/1.4731683","article-title":"A microcontroller-based lock-in amplifier for sub-milliohm resistance measurements","volume":"83","author":"Bengtsson","year":"2012","journal-title":"Rev. Sci. Instrum."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1937","DOI":"10.1063\/1.1353198","article-title":"Application of acoustic resonators in photoacoustic trace gas analysis and metrology","volume":"72","author":"Hess","year":"2001","journal-title":"Rev. Sci. Instrum."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/5\/1270\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T09:01:51Z","timestamp":1760173311000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/5\/1270"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,2,26]]},"references-count":25,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2020,3]]}},"alternative-id":["s20051270"],"URL":"https:\/\/doi.org\/10.3390\/s20051270","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,2,26]]}}}