{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2024,9,8]],"date-time":"2024-09-08T22:45:21Z","timestamp":1725835521772},"reference-count":39,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2021,3,17]],"date-time":"2021-03-17T00:00:00Z","timestamp":1615939200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2019M3F2A1073385"],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"This paper introduces a method for improving the sensitivity to NO2 gas of a p-type metal oxide semiconductor gas sensor. The gas sensor was fabricated using CuO nanowires (NWs) grown through thermal oxidation and decorated with ZnO nanoparticles (NPs) using a sol-gel method. The CuO gas sensor with a ZnO heterojunction exhibited better sensitivity to NO2 gas than the pristine CuO gas sensor. The heterojunction in CuO\/ZnO gas sensors caused a decrease in the width of the hole accumulation layer (HAL) and an increase in the initial resistance. The possibility to influence the width of the HAL helped improve the NO2 sensing characteristics of the gas sensor. The growth morphology, atomic composition, and crystal structure of the gas sensors were analyzed using field-emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy, and X-ray diffraction, respectively.<\/jats:p>","DOI":"10.3390\/s21062103","type":"journal-article","created":{"date-parts":[[2021,3,18]],"date-time":"2021-03-18T01:43:31Z","timestamp":1616031811000},"page":"2103","source":"Crossref","is-referenced-by-count":36,"title":["Decoration of CuO NWs Gas Sensor with ZnO NPs for Improving NO2 Sensing Characteristics"],"prefix":"10.3390","volume":"21","author":[{"given":"Tae-Hee","family":"Han","sequence":"first","affiliation":[{"name":"Department of Smart Interdisciplinary Engineering, Pusan National University, Busan 46241, Korea"}]},{"ORCID":"http:\/\/orcid.org\/0009-0001-3863-0265","authenticated-orcid":false,"given":"So-Young","family":"Bak","sequence":"additional","affiliation":[{"name":"Department of Electronics Engineering, Pusan National University, Busan 46241, Korea"}]},{"given":"Sangwoo","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Smart Interdisciplinary Engineering, Pusan National University, Busan 46241, Korea"}]},{"given":"Se Hyeong","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Electronics Engineering, Pusan National University, Busan 46241, Korea"}]},{"given":"Ye-Ji","family":"Han","sequence":"additional","affiliation":[{"name":"Department of Smart Interdisciplinary Engineering, Pusan National University, Busan 46241, Korea"}]},{"given":"Moonsuk","family":"Yi","sequence":"additional","affiliation":[{"name":"Department of Electronics Engineering, Pusan National University, Busan 46241, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1016\/j.snb.2004.12.075","article-title":"Toward innovations of gas sensor technology","volume":"108","author":"Yamazoe","year":"2005","journal-title":"Sens. Actuators B Chem."},{"key":"ref_2","first-page":"10","article-title":"Nanostructures gas sensors for health care: An Overview","volume":"1","author":"Kaushik","year":"2015","journal-title":"J. Pers. Nanomed."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"250","DOI":"10.1016\/j.snb.2014.07.074","article-title":"Nanoscale metal oxide-based heterojunctions for gas sensing: A review","volume":"204","author":"Miller","year":"2014","journal-title":"Sens. Actuators B Chem."},{"key":"ref_4","first-page":"206","article-title":"Semiconductor metal oxide gas sensors: A review","volume":"229","author":"Dey","year":"2018","journal-title":"Sens. Actuators B Chem."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1007\/s10832-009-9583-x","article-title":"Modeling of sensing and transduction for p-type semiconducting metal oxide based gas sensors","volume":"25","author":"Barsan","year":"2010","journal-title":"J. Electroceram."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"340","DOI":"10.1016\/j.snb.2013.01.018","article-title":"Modeling of a p-type resistive gas sensor in the presence of a reducing gas","volume":"181","author":"Bejaoui","year":"2013","journal-title":"Sens. Actuators B Chem."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"607","DOI":"10.1016\/j.snb.2013.11.005","article-title":"Highly sensitive and selective gas sensors using p-type oxide semiconductors: Overview","volume":"192","author":"Kim","year":"2014","journal-title":"Sens. Actuators B Chem."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"160","DOI":"10.1016\/S0925-4005(01)01031-0","article-title":"Gas sensing properties of p-type semiconducting Cr-doped TiO2 thin films","volume":"83","author":"Li","year":"2002","journal-title":"Sens. Actuators B Chem."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"753","DOI":"10.1016\/j.ceramint.2017.09.243","article-title":"Highly selective NO2 sensor based on p-type nanocrystalline NiO thin film prepared by sol-gel dip coating","volume":"44","author":"Zhao","year":"2018","journal-title":"Ceram. Int."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"2775","DOI":"10.1016\/j.tsf.2008.10.090","article-title":"Characterization of n-type and p-type semiconductor gas sensors based on NiOx doped TiO2 thin films","volume":"517","author":"Wisitsoraat","year":"2009","journal-title":"Thin Solid Films"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"485502","DOI":"10.1088\/0957-4484\/21\/48\/485502","article-title":"Conductometric chemical sensor based on individual CuO nanowires","volume":"21","author":"Li","year":"2010","journal-title":"Nanotechnology"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"111","DOI":"10.1080\/10408430490888977","article-title":"Oxide Materials for Development of Integrated Gas Sensors-A Comprehensive Review","volume":"29","author":"Eranna","year":"2004","journal-title":"Crit. Rev. Solid State Mater. Sci."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"181","DOI":"10.1108\/02602280410525977","article-title":"A review of gas sensors employed in electronic nose applications","volume":"24 No.2","author":"Arshak","year":"2004","journal-title":"Sens. Rev."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"235206","DOI":"10.1103\/PhysRevB.73.235206","article-title":"LSDA+U study of cupric oxide: Electronic structure and native point defects","volume":"73","author":"Wu","year":"2006","journal-title":"Phys. Rev. B"},{"key":"ref_15","first-page":"138","article-title":"Fabrication and Characterization of CuO-based Solar Cells","volume":"1","author":"Kidowaki","year":"2012","journal-title":"J. Mater. Sci. Res."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"506","DOI":"10.1016\/j.poly.2018.10.040","article-title":"Electrochemical synthesis and efficient photocatalytic degradation of azo dye alizarin yellow R by Cu\/CuO nanorods under visible LED light irradiation using experimental design methodology","volume":"158","author":"Barzegar","year":"2019","journal-title":"Polyhedron"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1267","DOI":"10.1016\/j.catcom.2006.11.019","article-title":"5.1% Apparent quantum efficiency for stable hydrogen generation over eosin-sensitized CuO\/TiO2 photocatalyst under visible light irradiation","volume":"8","author":"Jin","year":"2007","journal-title":"Catal. Commun."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"146","DOI":"10.1016\/j.physe.2009.09.016","article-title":"Facile synthesis of p-type semiconducting cupric oxide nanowires and their gas-sensing properties","volume":"42","author":"Hoa","year":"2009","journal-title":"Phys. E"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"260","DOI":"10.1002\/pssr.201510414","article-title":"Single and networked CuO nanowires for highly sensitive p-type semiconductor gas sensor applications","volume":"10","author":"Lupan","year":"2016","journal-title":"Phys. Status Solidi RRL"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"2440","DOI":"10.1021\/jp908850j","article-title":"Transport, Analyte Detection, and Opto-Electronic Response of p-Type CuO Nanowires","volume":"114","author":"Hansen","year":"2010","journal-title":"J. Phys. Chem. C"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"8013","DOI":"10.3390\/s120608013","article-title":"Selective Detection of NO2 Using Cr-doped CuO Nanorods","volume":"12","author":"Kim","year":"2012","journal-title":"Sensors"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"414","DOI":"10.1039\/C1RA01001H","article-title":"Design of highly sensitive volatile organic compound sensors by controlling NiO loading on ZnO nanowire networks","volume":"2","author":"Na","year":"2012","journal-title":"RSC Adv."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"465603","DOI":"10.1088\/0957-4484\/20\/46\/465603","article-title":"Synthesis of SnO2-ZnO core-shell nanofibers via a novel two-step process and their gas sensing properties","volume":"20","author":"Choi","year":"2009","journal-title":"Nanotechnology"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"13283","DOI":"10.1039\/C4TA01837K","article-title":"Solvothermal synthesis of ZnO-decorated \u03b1-Fe2O3 nanorods with highly enhanced gas-sensing performance toward n-butanol","volume":"2","author":"Kaneti","year":"2014","journal-title":"J. Mater. Chem. A"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1230","DOI":"10.1016\/j.apsusc.2016.06.007","article-title":"Preparation and characterization of ALD deposited ZnO thin films studied for gas sensors","volume":"387","author":"Boyadjiev","year":"2016","journal-title":"Appl. Surf. Sci."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"312","DOI":"10.1016\/j.snb.2004.04.061","article-title":"Microstructure control of thermally stable TiO2 obtained by hydrothermal process for gas sensors","volume":"103","author":"Ruiz","year":"2004","journal-title":"Sens. Actuators B Chem."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"31","DOI":"10.1016\/j.spmi.2004.08.021","article-title":"The effects of oxidative environments on the synthesis of CuO nanowires on Cu substrates","volume":"36","author":"Xu","year":"2004","journal-title":"Superlattices Microstruct."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Bak, S.-Y., Lee, J., Kim, Y., Lee, S.-H., Woo, K., Lee, S., and Yi, M. (2019). Sensitivity Improvement of Urchin-Like ZnO Nanostructures Using Two-Dimensional Electron Gas in MgZnO\/ZnO. Sensors, 19.","DOI":"10.3390\/s19235195"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"20129","DOI":"10.1021\/acsomega.9b01382","article-title":"Heterostructural CuO-ZnO Nanocomposites: A Highly Selective Chemical and Electrochemical NO2 Sensor","volume":"4","author":"Mali","year":"2019","journal-title":"ACS Omega"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"2079","DOI":"10.1016\/j.msec.2012.05.042","article-title":"CuO nanoparticle decorated ZnO nanorod sensor for low-temperature H2S detection","volume":"32","author":"Wang","year":"2012","journal-title":"Mater. Sci. Eng. C"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"8911","DOI":"10.1039\/C4TC01182A","article-title":"A novel approach to improving oxidizing-gas sensing ability of p-CuO nanowires using biased radial modulation of a hole-accumulation layer","volume":"2","author":"Choi","year":"2014","journal-title":"J. Mater. Chem. C"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"216","DOI":"10.1016\/S0925-4005(01)01043-7","article-title":"Diffusion equation-based study of thin film semiconductor gas sensor-response transient","volume":"83","author":"Matsunaga","year":"2002","journal-title":"Sens. Actuators B Chem."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"861","DOI":"10.1016\/S0026-2692(98)00019-6","article-title":"Sensitivity, response and recovery time of SnO2 based thick-film sensor array for H2, CO, CH4 and LPG","volume":"29","author":"Mishra","year":"1998","journal-title":"Microelectron. J."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"319","DOI":"10.1016\/j.snb.2009.04.026","article-title":"Gas sensors using hierarchical and hollow oxide nanostructures: Overview","volume":"140","author":"Lee","year":"2009","journal-title":"Sens. Actuators B Chem."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"242","DOI":"10.1016\/j.apsusc.2017.03.290","article-title":"Synthesis, characterization and gas sensing properties of ZnO-decorated MWCNTs","volume":"413","author":"Kwon","year":"2017","journal-title":"Appl. Surf. Sci."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"2380","DOI":"10.1016\/j.materresbull.2007.07.045","article-title":"CuO particles and plates: Synthesis and gas-sensor application","volume":"43","author":"Li","year":"2008","journal-title":"Mater. Res. Bull."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"298","DOI":"10.1016\/j.snb.2008.08.026","article-title":"CuO nanowire gas sensors for air quality control in automotive cabin","volume":"135","author":"Kim","year":"2008","journal-title":"Sens. Actuators B Chem."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"282","DOI":"10.1016\/j.snb.2014.06.118","article-title":"A ppb-level formaldehyde gas sensor based on CuO nanocubes prepared using a polyol process","volume":"203","author":"Park","year":"2014","journal-title":"Sens. Actuators B Chem."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"374","DOI":"10.1016\/j.jallcom.2016.02.197","article-title":"Heterojunction CuO@ZnO microcubes for superior p-type gas sensor application","volume":"672","author":"Yin","year":"2016","journal-title":"J. Alloys Compd."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/6\/2103\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,7,9]],"date-time":"2024-07-09T19:14:10Z","timestamp":1720552450000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/6\/2103"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,3,17]]},"references-count":39,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2021,3]]}},"alternative-id":["s21062103"],"URL":"https:\/\/doi.org\/10.3390\/s21062103","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,3,17]]}}}