In this work, we investigate ethanol (EtOH)-sensing mechanisms of a ZnO nanorod (NRs)-based chemiresistor using a near-ambient-pressure X-ray photoelectron spectroscopy (NAP-XPS). First, the ZnO NRs-based sensor was constructed, showing good performance on interaction with 100 ppm of EtOH in the ambient air at 327 °C. Then, the same ZnO NRs film was investigated by NAP-XPS in the presence of 1 mbar oxygen, simulating the ambient air atmosphere and O2/EtOH mixture at the same temperature. The partial pressure of EtOH was 0.1 mbar, which corresponded to the partial pressure of 100 ppm of analytes in the ambient air. To better understand the EtOH-sensing mechanism, the NAP-XPS spectra were also studied on exposure to O2/EtOH/H2O and O2/MeCHO (MeCHO = acetaldehyde) mixtures. Our results revealed that the reaction of EtOH with chemisorbed oxygen on the surface of ZnO NRs follows the acetaldehyde pathway. It was also demonstrated that, during the sensing process, the surface becomes contaminated by different products of MeCHO decomposition, which decreases dc-sensor performance. However, the ac performance does not seem to be affected by this phenomenon.

Department of Physics and Measurements University of Chemistry and Technology Prague Technická 5 166 28 Prague 6 Czech Republic

Department of Surface and Plasma Science Faculty of Mathematics and Physics Charles University 5 Holešovičkách 2 180 00 Prague 8 Czech Republic

Institute of Photonics and Electronics Czech Academy of Sciences Chaberská 1014 57 182 51 Prague 8 Czech Republic

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Norton D.P., Heo Y.W., Ivill M.P., Ip K., Pearton S.J., Chisholm M.F., Steiner T. ZnO: Growth, doping and processing. Mater. Today. 2008;7:34–40. doi: 10.1016/S1369-7021(04)00287-1. DOI

Kuld S., Thorhauge M., Falsig H., Elkjær C.F., Helveg S., Chorkendorff I., Sehested J. Quantifying the promotion of Cu catalysts by ZnO for methanol synthesis. Science. 2016;352:969–974. doi: 10.1126/science.aaf0718. PubMed DOI

Leschkies K.S., Divakar R., Basu J., Enache-Pommer E., Boercker J.E., Carter C.B., Kortshagen U.R., Norris D.J., Aydil E.S. Photosensitization of ZnO nanowires with CdSe quantum dots for photovoltaic devices. Nano Lett. 2007;7:1793–1798. doi: 10.1021/nl070430o. PubMed DOI

Vittal R., Ho K.C. Zinc oxide based dye-sensitized solar cells: A review. Renew. Sustain. Energy Rev. 2017;70:920–935. doi: 10.1016/j.rser.2016.11.273. DOI

Guo J., Zhang J., Zhu M., Ju D., Xu H., Cao B. High-performance gas sensor based on ZnO nanowires functionalized by Au nanoparticles. Sens. Actuators B Chem. 2014;199:339–345. doi: 10.1016/j.snb.2014.04.010. DOI

Kumar R., Al-Dossary O., Kumar G., Umar A. Zinc oxide nanostructures for NO2 gas–sensor applications: A review. NanoMicro Lett. 2015;7:97–120. doi: 10.1007/s40820-014-0023-3. PubMed DOI PMC

Maziarz W., Rydosz A., Pisarkiewicz T., Domański K., Grabiec P. Gas-sensitive properties of Zno nanorods/nanowires obtained by electrodeposition and electrospinning methods. Procedia Eng. 2012;47:841–844. doi: 10.1016/j.proeng.2012.09.278. DOI

Batzill M., Diebold U. The surface and materials science of tin oxide. Prog. Surf. Sci. 2005;79:47–154. doi: 10.1016/j.progsurf.2005.09.002. DOI

Seiyama T., Kato A., Fujiishi K., Nagatani M. A New Detector for Gaseous Components Using Semiconductive Thin Films. Anal. Chem. 1962;34:1502–1503. doi: 10.1021/ac60191a001. DOI

Suzuki T.T., Ohgaki T., Adachi Y., Sakaguchi I., Nakamura M., Ohashi H., Aimi A., Fujimoto K. Ethanol Gas Sensing by a Zn-Terminated ZnO(0001) Bulk Single- Crystalline Substrate. ACS Omega. 2020 doi: 10.1021/acsomega.0c02750. PubMed DOI PMC

Tharsika T., Thanihaichelvan M., Haseeb A.S.M.A., Akbar S.A. Highly sensitive and selective ethanol sensor based on zno nanorod on SnO2 thin film fabricated by spray pyrolysis. Front. Mater. 2019;6:1–9. doi: 10.3389/fmats.2019.00122. DOI

Kaur N., Singh M., Comini E. One-Dimensional Nanostructured Oxide Chemoresistive Sensors. Langmuir. 2020;36:6326–6344. doi: 10.1021/acs.langmuir.0c00701. PubMed DOI PMC

Yamazoe N. New approaches for improving semiconductor gas sensors. Sens. Actuators B Chem. 1991;5:7–19. doi: 10.1016/0925-4005(91)80213-4. DOI

Gurlo A. Interplay between O2 and SnO2: Oxygen ionosorption and spectroscopic evidence for adsorbed oxygen. ChemPhysChem. 2006;7:2041–2052. doi: 10.1002/cphc.200600292. PubMed DOI

Abokifa A.A., Haddad K., Fortner J., Lo C.S., Biswas P. Sensing mechanism of ethanol and acetone at room temperature by SnO2 nano-columns synthesized by aerosol routes: Theoretical calculations compared to experimental results. J. Mater. Chem. A. 2018;6:2053–2066. doi: 10.1039/C7TA09535J. DOI

Shankar P., Rayappan J.B.B. Room temperature ethanol sensing properties of ZnO nanorods prepared using an electrospinning technique. J. Mater. Chem. C. 2017;5:10869–10880. doi: 10.1039/C7TC03771F. DOI

Chen Y., Zhu C.L., Xiao G. Reduced-temperature ethanol sensing characteristics of flower-like ZnO nanorods synthesized by a sonochemical method. Nanotechnology. 2006;17:4537–4541. doi: 10.1088/0957-4484/17/18/002. PubMed DOI

Bhati V.S., Hojamberdiev M., Kumar M. Enhanced sensing performance of ZnO nanostructures-based gas sensors: A review. Energy Rep. 2020;6:46–62. doi: 10.1016/j.egyr.2019.08.070. DOI

Leonardi S.G. Two-dimensional zinc oxide nanostructures for gas sensor applications. Chemosensors. 2017;5:17. doi: 10.3390/chemosensors5020017. DOI

Zhu L., Zeng W. Room-temperature gas sensing of ZnO-based gas sensor: A review. Sens. Actuators A Phys. 2017;267:242–261. doi: 10.1016/j.sna.2017.10.021. DOI

Wang L., Kang Y., Liu X., Zhang S., Huang W., Wang S. ZnO nanorod gas sensor for ethanol detection. Sens. Actuators B Chem. 2012;162:237–243. doi: 10.1016/j.snb.2011.12.073. DOI

Roy S., Banerjee N., Sarkar C.K., Bhattacharyya P. Development of an ethanol sensor based on CBD grown ZnO nanorods. Solid State Electron. 2013;87:43–50. doi: 10.1016/j.sse.2013.05.003. DOI

Mani G.K., Rayappan J.B.B. ZnO nanoarchitectures: Ultrahigh sensitive room temperature acetaldehyde sensor. Sens. Actuators B Chem. 2016;223:343–351. doi: 10.1016/j.snb.2015.09.103. DOI

Nowicki M. A modified impedance-frequency converter for inexpensive inductive and resistive sensor applications. Sensors. 2019;19:121. doi: 10.3390/s19010121. PubMed DOI PMC

Bobkov A., Varezhnikov A., Plugin I., Fedorov F.S., Trouillet V., Geckle U., Sommer M., Goffman V., Moshnikov V., Sysoev V. The multisensor array based on grown-on-chip zinc oxide nanorod network for selective discrimination of alcohol vapors at sub-ppm range. Sensors. 2019;19:4265. doi: 10.3390/s19194265. PubMed DOI PMC

Gurlo A., Riedel R. In situ and operando spectroscopy for assessing mechanisms of gas sensing. Angew. Chem. Int. Ed. 2007;46:3826–3848. doi: 10.1002/anie.200602597. PubMed DOI

Hongsith N., Wongrat E., Kerdcharoen T., Choopun S. Sensor response formula for sensor based on ZnO nanostructures. Sens. Actuators B Chem. 2010;144:67–72. doi: 10.1016/j.snb.2009.10.037. DOI

Geunjae K., Kijung Y. Adsorption and reaction of ethanol on ZnO nanowires. J. Phys. Chem. C. 2008;112:3036–3041.

Xu J., Han J., Zhang Y., Sun Y., Xie B. Studies on alcohol sensing mechanism of ZnO based gas sensors. Sens. Actuators B Chem. 2008;132:334–339. doi: 10.1016/j.snb.2008.01.062. DOI

Baikie I.D., Grain A., Sutherland J., Law J. Near ambient pressure photoemission spectroscopy of metal and semiconductor surfaces. Phys. Status Solidi. 2015;12:259–262. doi: 10.1002/pssc.201400086. DOI

Prosvirin I.P., Bukhtiyarov A.V., Bluhm H., Bukhtiyarov V.I. Application of near ambient pressure gas-phase X-ray photoelectron spectroscopy to the investigation of catalytic properties of copper in methanol oxidation. Appl. Surf. Sci. 2016;363:303–309. doi: 10.1016/j.apsusc.2015.11.258. DOI

Wolfbeisser A., Kovács G., Kozlov S.M., Föttinger K., Bernardi J., Klötzer B., Neyman K.M., Rupprechter G. Surface composition changes of CuNi-ZrO2 during methane decomposition: An operando NAP-XPS and density functional study. Catal. Today. 2017;283:134–143. doi: 10.1016/j.cattod.2016.04.022. DOI

Vorokhta M., Khalakhan I., Vondráček M., Tomeček D., Vorokhta M., Marešová E., Nováková J., Vlček J., Fitl P., Novotný M., et al. Investigation of gas sensing mechanism of SnO2 based chemiresistor using near ambient pressure XPS. Surf. Sci. 2018;687:284–290. doi: 10.1016/j.susc.2018.08.003. DOI

Hozák P., Vorokhta M., Khalakhan I., Jarkovská K., Cibulková J., Fitl P., Vlček J., Fara J., Tomeček D., Novotný M., et al. New Insight into the Gas-Sensing Properties of CuOx Nanowires by Near-Ambient Pressure XPS. J. Phys. Chem. C. 2019;123:29739–29749. doi: 10.1021/acs.jpcc.9b09124. DOI

Yatskiv R., Tiagulskyi S., Grym J., Vaniš J., Bašinová N., Horak P., Torrisi A., Ceccio G., Vacik J., Vrňata M. Optical and electrical characterization of CuO/ZnO heterojunctions. Thin Solid Films. 2020;693:137656. doi: 10.1016/j.tsf.2019.137656. DOI

Tomecek D., Hruska M., Fitl P., Vlcek J., Maresova E., Havlova S., Patrone L., Vrnata M. Phthalocyanine Photoregeneration for Low Power Consumption Chemiresistors. ACS Sens. 2018;3:2558–2565. doi: 10.1021/acssensors.8b00922. PubMed DOI

Myslík V., Vysloužil F., Vrňata M., Rozehnal Z., Jelíinek M., Fryček R., Kovanda M. Phase ac-sensitivity of oxidic and acetylacetonic gas sensors. Sens. Actuators B Chem. 2003;89:205–211. doi: 10.1016/S0925-4005(02)00466-5. DOI

Fitl P., Vrnata M., Kopecky D., Vlcek J., Skodova J., Bulir J., Novotny M., Pokorny P. Laser deposition of sulfonated phthalocyanines for gas sensors. Appl. Surf. Sci. 2014;302:37–41. doi: 10.1016/j.apsusc.2014.01.128. DOI

Mudiyanselage K., Burrell A.K., Senanayake S.D., Idriss H. XPS and NEXAFS study of the reactions of acetic acid and acetaldehyde over UO2(100) thin film. Surf. Sci. 2019;680:107–112. doi: 10.1016/j.susc.2018.10.017. DOI

Jacobs G., Keogh R.A., Davis B.H. Steam reforming of ethanol over Pt/ceria with co-fed hydrogen. J. Catal. 2007;245:326–337. doi: 10.1016/j.jcat.2006.10.018. DOI

Vohs J.M., Barteau M.A. Formation of Stable Alkyl and Carboxylate Intermediates in the Reactions of Aldehydes on the ZnO(0001) Surface. Langmuir. 1989;5:965–972. doi: 10.1021/la00088a015. DOI

Singh M., Kaur N., Drera G., Casotto A., Ermenegildo L.S., Comini E. SAM Functionalized ZnO Nanowires for Selective Acetone Detection: Optimized Surface Specific Interaction Using APTMS and GLYMO Monolayers. Adv. Funct. Mater. 2020;2003217:1–12. doi: 10.1002/adfm.202003217. DOI

Zuo J., Erbe A. Optical and electronic properties of native zinc oxide films on polycrystalline Zn. Phys. Chem. Chem. Phys. 2010;12:11467–11476. doi: 10.1039/c004532b. PubMed DOI

Wang C., Yin L., Zhang L., Xiang D., Gao R. Metal oxide gas sensors: Sensitivity and influencing factors. Sensors. 2010;10:2088–2106. doi: 10.3390/s100302088. PubMed DOI PMC

Zimmermann P., Sobotík P., Kocán P., Ošt’Ádal I., Vorokhta M., Acres R.G., Matolín V. Adsorption of ethylene on Sn and in terminated Si(001) surface studied by photoelectron spectroscopy and scanning tunneling microscopy. J. Chem. Phys. 2016;145:094701. doi: 10.1063/1.4961737. PubMed DOI

Rai P., Yu Y.T. Citrate-assisted hydrothermal synthesis of single crystalline ZnO nanoparticles for gas sensor application. Sens. Actuators B Chem. 2012;173:58–65. doi: 10.1016/j.snb.2012.05.068. DOI

Saboor F.H., Khodadadi A.A., Mortazavi Y., Asgari M. Microemulsion synthesized silica/ZnO stable core/shell sensors highly selective to ethanol with minimum sensitivity to humidity. Sens. Actuators B Chem. 2017;238:1070–1083. doi: 10.1016/j.snb.2016.07.127. DOI

Kunat M., Girol S.G., Burghaus U., Wöll C. The Interaction of Water with the Oxygen-Terminated, Polar Surface of ZnO. J. Phys. Chem. B. 2003;107:14350–14356. doi: 10.1021/jp030675z. DOI