J. Semicond. > 2025, Volume 46 > Issue 3 > 032101
|

ARTICLES

Fabrication and application of SiNWs based PANI:MOx heterostructures for human respiratory monitoring

Muhammad Taha Sultan1, 3, , Anca Dumitru2, Elham Fakhri1, Rachel Brophy1, Snorri Thorgeir Ingvarsson3, Andrei Manolescu1 and Halldor Gudfinur Svavarsson1

+ Author Affiliations

 Corresponding author: Muhammad Taha Sultan, muhammads@ru.is

DOI: 10.1088/1674-4926/24090035CSTR: 32376.14.1674-4926.24090035

PDF

Turn off MathJax

Abstract: In this study, we investigate an innovative hybrid structure of silicon nanowires (SiNWs) coated with polyaniline (PANI):metal oxide (MOx) nanoparticles, i.e., WO3 and TiO2, for respiratory sensing. To date, few attempts have been made to utilize such hybrid structures for that application. The SiNWs were fabricated using metal-assisted chemical etching (MACE), whereas PANI:MOx was deposited using chemical oxidative polymerization. The structures were characterized using Raman spectroscopy, X-ray diffraction, and scanning electron microscopy. The sensing characteristics revealed that the hybrid sensor exhibited a considerably better response than pure SiNWs:MOx and SiNWs:PANI. Such an enhancement in sensitivity is attributed to the formation of a p−n heterojunction between PANI and MOx, the wider conduction channel provided by PANI, increased porosity in SiNWs/PANI:WO3 hybrid structures, which creates active sites, increased oxygen vacancies, and the large surface area compared to that available in pure MOx nanoparticles. Furthermore, less baseline drift and increased sensor stability were established for the SiNWs structure coated with PANI:WO3, as compared to PANI:TiO2.

Key words: SiNWs, metal oxides, sensor, XRD, Raman spectroscopy, scanning electron micrscopy



[1]
Akbari-Saatlu M, Procek M, Mattsson C, et al. Silicon nanowires for gas sensing: A review. Nanomaterials, 2020, 10, 2215 doi: 10.3390/nano10112215
[2]
Yu S G, Zhang H Y, Zhang J, et al. High-sensitivity RGO-TiO2 humidity sensor driven by triboelectric nanogenerators for non-contact monitoring of human respiration. J Alloys Compd, 2023, 935, 168006 doi: 10.1016/j.jallcom.2022.168006
[3]
Andreozzi E, Centracchio J, Punzo V, et al. Respiration monitoring via forcecardiography sensors. Sensors, 2021, 21, 3996 doi: 10.3390/s21123996
[4]
Mansour E, Vishinkin R, Rihet S, et al. Measurement of temperature and relative humidity in exhaled breath. Sens Actuat B Chem, 2020, 304, 127371 doi: 10.1016/j.snb.2019.127371
[5]
Wang C X, Yin L W, Zhang L Y, et al. Metal oxide gas sensors: Sensitivity and influencing factors. Sensors, 2010, 10, 2088 doi: 10.3390/s100302088
[6]
Liu X, Cheng S, Liu H, et al. A survey on gas sensing technology. Sensors (Basel), 2012, 12, 9635 doi: 10.3390/s120709635
[7]
Panigrahi P K, Chandu B, Puvvada N. Recent advances in nanostructured materials for application as gas sensors. ACS Omega, 2024, 9, 3092 doi: 10.1021/acsomega.3c06533
[8]
Guo S Y, Hou P X, Zhang F, et al. Gas sensors based on single-wall carbon nanotubes. Molecules, 2022, 27, 5381 doi: 10.3390/molecules27175381
[9]
Kong Y L, Li Y X, Cui X X, et al. SnO2 nanostructured materials used as gas sensors for the detection of hazardous and flammable gases: A review. Nano Mater Sci, 2022, 4, 339 doi: 10.1016/j.nanoms.2021.05.006
[10]
Sun Y F, Liu S B, Meng F L, et al. Metal oxide nanostructures and their gas sensing properties: A review. Sensors, 2012, 12, 2610 doi: 10.3390/s120302610
[11]
Ji F X, Ren X P, Zheng X Y, et al. 2D-MoO3 nanosheets for superior gas sensors. Nanoscale, 2016, 8, 8696 doi: 10.1039/C6NR00880A
[12]
Umar A, Alshahrani A A, Algarni H, et al. CuO nanosheets as potential scaffolds for gas sensing applications. Sens Actuat B Chem, 2017, 250, 24 doi: 10.1016/j.snb.2017.04.062
[13]
Comini E. Metal oxides nanowires chemical/gas sensors: Recent advances. Mater Today Adv, 2020, 7, 100099 doi: 10.1016/j.mtadv.2020.100099
[14]
Fakhri E, Sultan M T, Manolescu A, et al. Application of p- and n-type silicon nanowires as human respiratory sensing device. Sensors, 2023, 23, 9901 doi: 10.3390/s23249901
[15]
Kale P, Sahoo M K. Removal of Ag remanence and improvement in structural attributes of silicon nanowires array via sintering. Sci Rep, 2021, 11, 24189 doi: 10.1038/s41598-021-03654-5
[16]
Huang Z P, Geyer N, Werner P, et al. Metal-assisted chemical etching of silicon: A review. Adv Mater, 2011, 23, 285 doi: 10.1002/adma.201001784
[17]
Fakhri E, Sultan M T, Manolescu A, et al. Synthesis and photoluminescence study of silicon nanowires obtained by metal assisted chemical etching. 2021 International Semiconductor Conference (CAS), 2021, 147 doi: 10.1109/CAS52836.2021.9604178
[18]
He W S, Zhao Y H, Xiong Y H. Bilayer polyaniline-WO3 thin-film sensors sensitive to NO2. ACS Omega, 2020, 5, 9744 doi: 10.1021/acsomega.9b04122
[19]
Masuda Y, Uozumi A. Highly responsive diabetes and asthma sensors with WO3 nanoneedle films for the detection of biogases with low concentrations. NPG Asia Mater, 2023, 15, 69 doi: 10.1038/s41427-023-00515-7
[20]
Kulkarni S B, Navale Y H, Navale S T, et al. Hybrid polyaniline-WO3 flexible sensor: A room temperature competence towards NH3 gas. Sens Actuat B Chem, 2019, 288, 279 doi: 10.1016/j.snb.2019.02.094
[21]
Bandgar D K, Navale S T, Naushad M, et al. Ultra-sensitive polyaniline–iron oxide nanocomposite room temperature flexible ammonia sensor. RSC Adv, 2015, 5, 68964 doi: 10.1039/C5RA11512D
[22]
Bonyani M, Zebarjad S M, Janghorban K, et al. Enhanced NO2 gas sensing properties of ZnO-PANI composite nanofibers. Ceram Int, 2023, 49, 1238 doi: 10.1016/j.ceramint.2022.09.103
[23]
Pippara R K, Chauhan P S, Yadav A, et al. Room temperature hydrogen sensing with polyaniline/SnO2/Pd nanocomposites. Micro Nano Eng, 2021, 12, 100086 doi: 10.1016/j.mne.2021.100086
[24]
Tian J F, Yang G, Jiang D G, et al. A hybrid material consisting of bulk-reduced TiO2, graphene oxide and polyaniline for resistance based sensing of gaseous ammonia at room temperature. Microchim Acta, 2016, 183, 2871 doi: 10.1007/s00604-016-1912-6
[25]
Kumar R, Yadav B C. Fabrication of polyaniline (PANI)—tungsten oxide (WO3) composite for humidity sensing application. J Inorg Organomet Polym Mater, 2016, 26, 1421 doi: 10.1007/s10904-016-0412-9
[26]
Mhamdi H, Zaghouani R B, Fiorido T, et al. Study of n-WO3/p-porous silicon structures for gas-sensing applications. J Mater Sci Mater Electron, 2020, 31, 7862 doi: 10.1007/s10854-020-03324-8
[27]
Chaudhary V, Kaur A. Enhanced room temperature sulfur dioxide sensing behaviour of in situ polymerized polyaniline–tungsten oxide nanocomposite possessing honeycomb morphology. RSC Adv, 2015, 5, 73535 doi: 10.1039/C5RA08275G
[28]
Wang Z H, Lan K B, Wang Z, et al. High-performance PANI sensor on silicon nanowire arrays for sub-ppb NH3 detection. Talanta, 2025, 282, 127086 doi: 10.1016/j.talanta.2024.127086
[29]
Jain A, Nabeel A N, Bhagwat S, et al. Fabrication of polypyrrole gas sensor for detection of NH3 using an oxidizing agent and pyrrole combinations: Studies and characterizations. Heliyon, 2023, 9, e17611 doi: 10.1016/j.heliyon.2023.e17611
[30]
Khuspe G D, Bandgar D K, Sen S, et al. Fussy nanofibrous network of polyaniline (PANi) for NH3 detection. Synth Met, 2012, 162, 1822 doi: 10.1016/j.synthmet.2012.08.022
[31]
Huang J, Yang T L, Kang Y F, et al. Gas sensing performance of polyaniline/ZnO organic-inorganic hybrids for detecting VOCs at low temperature. J Nat Gas Chem, 2011, 20, 515 doi: 10.1016/S1003-9953(10)60230-7
[32]
Fratoddi I, Venditti I, Cametti C, et al. Chemiresistive polyaniline-based gas sensors: A mini review. Sens Actuat B Chem, 2015, 220, 534 doi: 10.1016/j.snb.2015.05.107
[33]
Duong N H, Nguyen T T, Nguyen D T, et al. Effect of TiO2 on the gas sensing features of TiO2/PANi nanocomposites. Sensors, 2011, 11, 1924 doi: 10.3390/s110201924
[34]
Li S Q, Lin P F, Zhao L P, et al. The room temperature gas sensor based on Polyaniline@flower-like WO3 nanocomposites and flexible PET substrate for NH3 detection. Sens Actuat B Chem, 2017, 259, 505 doi: 10.1016/j.snb.2017.11.081
[35]
Lascu I, Locovei C, Bradu C, et al. Polyaniline-derived nitrogen-containing carbon nanostructures with different morphologies as anode modifier in microbial fuel cells. Int J Mol Sci, 2022, 23, 11230 doi: 10.3390/ijms231911230
[36]
Xu L J, Yin M L, Liu S F. Ag(x)@WO3 core-shell nanostructure for LSP enhanced chemical sensors. Sci Rep, 2014, 4, 6745 doi: 10.1038/srep06745
[37]
Challagulla S, Tarafder K, Ganesan R, et al. Structure sensitive photocatalytic reduction of nitroarenes over TiO2. Sci Rep, 2017, 7, 8783 doi: 10.1038/s41598-017-08599-2
[38]
Hardcastle F D. Raman spectroscopy of titania (TiO2) nanotubular water-splitting catalysts. Arkansas Academy Science, 2011, 65, 43 doi: 10.54119/jaas.2011.6504
[39]
Mousli F, Chaouchi A, Hocine S, et al. Diazonium-modified TiO2/polyaniline core/shell nanoparticles. Structural characterization, interfacial aspects and photocatalytic performances. Appl Surf Sci, 2019, 465, 1078 doi: 10.1016/j.apsusc.2018.09.252
[40]
Pakdel H, Galstyan V, D’Arco A, et al. Synthesis of WO3 nanopowder using a green surfactant for efficient gas sensing applications. Ceram Int, 2023, 49, 30501 doi: 10.1016/j.ceramint.2023.06.314
[41]
Aldrees A, Khan H, Alzahrani A, et al. Synthesis and characterization of tungsten trioxide (WO3) as photocatalyst against wastewater pollutants. Appl Water Sci, 2023, 13, 156 doi: 10.1007/s13201-023-01938-x
[42]
Ishida Y, Motono S, Doshin W, et al. Small nanosized oxygen-deficient tungsten oxide particles: Mechanistic investigation with controlled plasma generation in water for their preparation. ACS Omega, 2017, 2, 5104 doi: 10.1021/acsomega.7b00986
[43]
Fewster P. Reciprocal space mapping. Crit Rev Solid State Mater Sci, 1996, 22, 269 doi: 10.1080/10408439708241259
[44]
Stanchu H V, Kuchuk A V, Barchuk M, et al. Asymmetrical reciprocal space mapping using X-ray diffraction: A technique for structural characterization of GaN/AlN superlattices. Cryst Eng Comm, 2017, 19, 2977 doi: 10.1039/C7CE00584A
[45]
Tai H L, Wang S, Duan Z H, et al. Evolution of breath analysis based on humidity and gas sensors: Potential and challenges. Sens Actuat B Chem, 2020, 318, 128104 doi: 10.1016/j.snb.2020.128104
[46]
Ates H C, Dincer C. Wearable breath analysis. Nat Rev Bioeng, 2023, 1, 80 doi: 10.1038/s44222-022-00011-7
[47]
Fakhri E, Plugaru R, Sultan M T, et al. Piezoresistance characterization of silicon nanowires in uniaxial and isostatic pressure variation. Sensors, 2022, 22, 6340 doi: 10.3390/s22176340
[48]
Zhang S S, Lou L, Lee C K. Piezoresistive silicon nanowire based nanoelectromechanical system cantilever air flow sensor. Appl Phys Lett, 2012, 100, 023111 doi: 10.1063/1.3675878
[49]
Kim C, Ahn H, Ji T. Flexible pressure sensors based on silicon nanowire array built by metal-assisted chemical etching. IEEE Electron Device Lett, 2020, 41, 1233 doi: 10.1109/LED.2020.3001977
[50]
Ghosh R, Song M S, Park J, et al. Fabrication of piezoresistive Si nanorod-based pressure sensor arrays: A promising candidate for portable breath monitoring devices. Nano Energy, 2021, 80, 105537 doi: 10.1016/j.nanoen.2020.105537
[51]
Song Y H, Shu C, Song Z H, et al. Self-powered health monitoring with ultrafast response and recovery enabled by nanostructured silicon moisture-electric generator. Chem Eng J, 2023, 468, 143797 doi: 10.1016/j.cej.2023.143797
[52]
Qin Y X, Jiang Y Q, Zhao L M. Modulation of agglomeration of vertical porous silicon nanowires and the effect on gas-sensing response. Adv Eng Mater, 2018, 20, 1700893 doi: 10.1002/adem.201700893
[53]
Morganti D, Leonardi A A, Lo Faro M J, et al. Ultrathin silicon nanowires for optical and electrical nitrogen dioxide detection. Nanomaterials, 2021, 11, 1767 doi: 10.3390/nano11071767
[54]
Park S B, Khattar D. Tachypnea. Emerg Office Pediatr, 2024, 8, 33
[55]
Lou C G, Hou K X, Zhu W T, et al. Human respiratory monitoring based on Schottky resistance humidity sensors. Materials, 2020, 13, 430 doi: 10.3390/ma13020430
[56]
Kundu S, Majumder R, Ghosh R, et al. Relative humidity sensing properties of doped polyaniline-encased multiwall carbon nanotubes: Wearable and flexible human respiration monitoring application. J Mater Sci, 2020, 55, 3884 doi: 10.1007/s10853-019-04276-z
[57]
Ekande O S, Kumar M. Review on polyaniline as reductive photocatalyst for the construction of the visible light active heterojunction for the generation of reactive oxygen species. J Environ Chem Eng, 2021, 9, 105725 doi: 10.1016/j.jece.2021.105725
[58]
Xie H, Li N, Chen X Z, et al. Surface oxygen vacancies promoted photodegradation of benzene on TiO2 film. Appl Surf Sci, 2020, 511, 145597 doi: 10.1016/j.apsusc.2020.145597
[59]
Chen H, Liu Y, Xie C S, et al. A comparative study on UV light activated porous TiO2 and ZnO film sensors for gas sensing at room temperature. Ceram Int, 2012, 38, 503 doi: 10.1016/j.ceramint.2011.07.035
[60]
Rahman K H, Kar A K. Effect of band gap variation and sensitization process of polyaniline (PANI)-TiO2 p−n heterojunction photocatalysts on the enhancement of photocatalytic degradation of toxic methylene blue with UV irradiation. J Environ Chem Eng, 2020, 8, 104181 doi: 10.1016/j.jece.2020.104181
[61]
Nunes D, Fortunato E, Martins R. Flexible nanostructured TiO2-based gas and UV sensors: A review. Discov Mater, 2022, 2, 2 doi: 10.1007/s43939-022-00023-5
[62]
Liu D, Lin L M, Chen Q F, et al. Low power consumption gas sensor created from silicon nanowires/TiO2 core–shell heterojunctions. ACS Sens, 2017, 2, 1491 doi: 10.1021/acssensors.7b00459
[63]
Qin Y X, Wang Z F, Liu D, et al. Dendritic composite array of silicon nanowires/WO3 nanowires for sensitive detection of NO2 at room temperature. Mater Lett, 2017, 207, 29 doi: 10.1016/j.matlet.2017.07.042
[64]
Staerz A, Weimar U, Barsan N. Understanding the potential of WO3 based sensors for breath analysis. Sensors, 2016, 16, 1815 doi: 10.3390/s16111815
[65]
Kim S J, Choi S J, Jang J S, et al. Mesoporous WO3 nanofibers with protein-templated nanoscale catalysts for detection of trace biomarkers in exhaled breath. ACS Nano, 2016, 10, 5891 doi: 10.1021/acsnano.6b01196
[66]
Xu M T, Wang Y J, Chen F C, et al. Breathable Nanomesh pressure sensor with layered polyaniline grown at gas-liquid interface. Chem Eng J, 2022, 445, 136717 doi: 10.1016/j.cej.2022.136717
[67]
Wang X W, Zhang D Z, Zhang H B, et al. In situ polymerized polyaniline/MXene (V2C) as building blocks of supercapacitor and ammonia sensor self-powered by electromagnetic-triboelectric hybrid generator. Nano Energy, 2021, 88, 106242 doi: 10.1016/j.nanoen.2021.106242
[68]
Beygisangchin M, Hossein Baghdadi A, Kartom Kamarudin S, et al. Recent progress in polyaniline and its composites; Synthesis, properties, and applications. Eur Polym J, 2024, 210, 112948 doi: 10.1016/j.eurpolymj.2024.112948
[69]
Han B, Popov A L, Shekunova T O, et al. Highly crystalline WO3 nanoparticles are nontoxic to stem cells and cancer cells. J Nanomater, 2019, 5384132 doi: 10.1155/2019/5384132
Fig. 1.  (Color online) Schematic representation of randomly aligned vertical SiNWs using MACE.

DownLoad: Full-Size Img PowerPoint
Fig. 2.  (Color online) Representation of structural schemes considered for respiratory sensing mechanism, i.e., (a) SiNWs with PANI, (b) SiNWs with MOx particles and (c) SiNWs coated with hybrid PANI:MOx nanocomposite. (d) A schematic representation of structure with metal contacts.

DownLoad: Full-Size Img PowerPoint
Fig. 3.  (Color online) Room temperature Raman spectra of WO3 and TiO2 nanopowder. The respetive peaks are marked for both WO3 and TiO2, respectively. In (b) the dotted line represents the Raman modes of anatase TiO2 whereas the solid line represents rutile TiO2.

DownLoad: Full-Size Img PowerPoint
Fig. 4.  (Color online) Room temperature Raman spectra of SiNWs structure coated with PANI, PANI:WO3, and PANI:TiO2. The Raman peaks are marked for PANI and that for WO3 and TiO2, respectively .

DownLoad: Full-Size Img PowerPoint
Fig. 5.  (Color online) XRD diffractogram for (a) polyaniline (b) WO3 nanopowder and TiO2 nanopowder. The green indicated lines in (b) and (c) represent the standard tabulated position of WO3 and anatase (a-TiO2) and the red indicated line in (c) represents the standard tabulated position for rutile(r)-TiO2, according to JCPDS no. 98-007-1692, 00-021-1272, and 00-021-1276, respectively.

DownLoad: Full-Size Img PowerPoint
Fig. 6.  (Color online) Reciprocal space map of (a) SiNWs and (b) SiNWs with PANI along (004) crystallographic plane.

DownLoad: Full-Size Img PowerPoint
Fig. 7.  (Color online) SEM microgrpahs. (a) and (b) cross-sectional and top-view of SiNWs structures obtained by MACE, (c) top-view of SiNWs coated with PANI, (d) and (e) cross-sectional and top-view of SiNWs coated with PANI:TiO2, (f) top-view of SiNWs coated with PANI:WO3, along with a magnified image showing the presence of NWs, (g) and (h) cross-sectional and top-view of SiNWs spin-coated with WO3, respectively. The scale bars are provided along with each figure.

DownLoad: Full-Size Img PowerPoint
Fig. 8.  (Color online) A schematic illustration of SiNWs sensing mechanism based on the bundling with NW−NW junction, demonstrating the modulation in potential barrier in air and during exposure to oxidizing and reducing analyte, respectively.

DownLoad: Full-Size Img PowerPoint
Fig. 9.  (Color online) Respiratory sensing for three different breathing patterns i.e., (a)−(c) normal, rapid, and deep breathing, respectively, using SiNWs structures decorated with PANI and PANI:MOx, respectively. The highlighted regions represent the exhaling and inhaling stimulus characteristics.

DownLoad: Full-Size Img PowerPoint
Fig. 10.  (Color online) Schematic illustration of p−n junction formation in (a) hybrid p-type PANI encapsulating n-type MOx nanoparticles. The figure demonstrate the depletion layer width alteration in air and in presence of oxidizing or reducing agent. (b) Potential band alignment and charge transfer in p-type SiNWs coated with hybrid of p-PANI:n-WO3. (c) Energy band with p−n junction formed between p-type SiNWs spin coated with n-type MOx nanoparticles.

DownLoad: Full-Size Img PowerPoint
Fig. 11.  (Color online) (a) Room temperature plot of dR/dt for SiNWs structure with and without hybrid PANI:WO3 deposition, respectively. The inset shows the resistance vs time plot of SiNWs with arrow representing a drift in baseline. (b) Plot for room temperature change in resistance as a function of time under varying breathing stimulus using SiNWs structures decorated with (top) PANI:WO3 using electroless deposition and (bottom) WO3 nanoparticles using spin-coating, respectively. The insets show magnified pattern under rapid breathing.

DownLoad: Full-Size Img PowerPoint
Fig. 12.  (Color online) Response of the structure (SiNWs/ PANI: WO3) after shelving for more than two-months.

DownLoad: Full-Size Img PowerPoint
Fig. 13.  (Color online) (a) Photograph of data acquisition electronics, utilizing an oscilloscope, assisted with Arduino microcontroller board (not shown here). (b) 3D printed mask with an outer cover for mounting sample and an inner grid which can be integrated with course filter for damage protection. (c) Sample before mounting with size ~10 × 10 mm2. (d) Circuit diagram of breath sensor.

DownLoad: Full-Size Img PowerPoint

Table 1.   Response time calculated from Fig. 9 for respective structures.

Structures Rt (s)
NB TB DB
SiNWs/PANI 1.32 0.18 1.63
SiNWs/PANI:TiO2 0.44 0.21 0.68
SiNWs/PANI:WO3 0.37 0.15 0.45
SiNWs/WO3 0.45 0.3 1.18
SiNWs 0.72 0.37 1.45
DownLoad: CSV
[1]
Akbari-Saatlu M, Procek M, Mattsson C, et al. Silicon nanowires for gas sensing: A review. Nanomaterials, 2020, 10, 2215 doi: 10.3390/nano10112215
[2]
Yu S G, Zhang H Y, Zhang J, et al. High-sensitivity RGO-TiO2 humidity sensor driven by triboelectric nanogenerators for non-contact monitoring of human respiration. J Alloys Compd, 2023, 935, 168006 doi: 10.1016/j.jallcom.2022.168006
[3]
Andreozzi E, Centracchio J, Punzo V, et al. Respiration monitoring via forcecardiography sensors. Sensors, 2021, 21, 3996 doi: 10.3390/s21123996
[4]
Mansour E, Vishinkin R, Rihet S, et al. Measurement of temperature and relative humidity in exhaled breath. Sens Actuat B Chem, 2020, 304, 127371 doi: 10.1016/j.snb.2019.127371
[5]
Wang C X, Yin L W, Zhang L Y, et al. Metal oxide gas sensors: Sensitivity and influencing factors. Sensors, 2010, 10, 2088 doi: 10.3390/s100302088
[6]
Liu X, Cheng S, Liu H, et al. A survey on gas sensing technology. Sensors (Basel), 2012, 12, 9635 doi: 10.3390/s120709635
[7]
Panigrahi P K, Chandu B, Puvvada N. Recent advances in nanostructured materials for application as gas sensors. ACS Omega, 2024, 9, 3092 doi: 10.1021/acsomega.3c06533
[8]
Guo S Y, Hou P X, Zhang F, et al. Gas sensors based on single-wall carbon nanotubes. Molecules, 2022, 27, 5381 doi: 10.3390/molecules27175381
[9]
Kong Y L, Li Y X, Cui X X, et al. SnO2 nanostructured materials used as gas sensors for the detection of hazardous and flammable gases: A review. Nano Mater Sci, 2022, 4, 339 doi: 10.1016/j.nanoms.2021.05.006
[10]
Sun Y F, Liu S B, Meng F L, et al. Metal oxide nanostructures and their gas sensing properties: A review. Sensors, 2012, 12, 2610 doi: 10.3390/s120302610
[11]
Ji F X, Ren X P, Zheng X Y, et al. 2D-MoO3 nanosheets for superior gas sensors. Nanoscale, 2016, 8, 8696 doi: 10.1039/C6NR00880A
[12]
Umar A, Alshahrani A A, Algarni H, et al. CuO nanosheets as potential scaffolds for gas sensing applications. Sens Actuat B Chem, 2017, 250, 24 doi: 10.1016/j.snb.2017.04.062
[13]
Comini E. Metal oxides nanowires chemical/gas sensors: Recent advances. Mater Today Adv, 2020, 7, 100099 doi: 10.1016/j.mtadv.2020.100099
[14]
Fakhri E, Sultan M T, Manolescu A, et al. Application of p- and n-type silicon nanowires as human respiratory sensing device. Sensors, 2023, 23, 9901 doi: 10.3390/s23249901
[15]
Kale P, Sahoo M K. Removal of Ag remanence and improvement in structural attributes of silicon nanowires array via sintering. Sci Rep, 2021, 11, 24189 doi: 10.1038/s41598-021-03654-5
[16]
Huang Z P, Geyer N, Werner P, et al. Metal-assisted chemical etching of silicon: A review. Adv Mater, 2011, 23, 285 doi: 10.1002/adma.201001784
[17]
Fakhri E, Sultan M T, Manolescu A, et al. Synthesis and photoluminescence study of silicon nanowires obtained by metal assisted chemical etching. 2021 International Semiconductor Conference (CAS), 2021, 147 doi: 10.1109/CAS52836.2021.9604178
[18]
He W S, Zhao Y H, Xiong Y H. Bilayer polyaniline-WO3 thin-film sensors sensitive to NO2. ACS Omega, 2020, 5, 9744 doi: 10.1021/acsomega.9b04122
[19]
Masuda Y, Uozumi A. Highly responsive diabetes and asthma sensors with WO3 nanoneedle films for the detection of biogases with low concentrations. NPG Asia Mater, 2023, 15, 69 doi: 10.1038/s41427-023-00515-7
[20]
Kulkarni S B, Navale Y H, Navale S T, et al. Hybrid polyaniline-WO3 flexible sensor: A room temperature competence towards NH3 gas. Sens Actuat B Chem, 2019, 288, 279 doi: 10.1016/j.snb.2019.02.094
[21]
Bandgar D K, Navale S T, Naushad M, et al. Ultra-sensitive polyaniline–iron oxide nanocomposite room temperature flexible ammonia sensor. RSC Adv, 2015, 5, 68964 doi: 10.1039/C5RA11512D
[22]
Bonyani M, Zebarjad S M, Janghorban K, et al. Enhanced NO2 gas sensing properties of ZnO-PANI composite nanofibers. Ceram Int, 2023, 49, 1238 doi: 10.1016/j.ceramint.2022.09.103
[23]
Pippara R K, Chauhan P S, Yadav A, et al. Room temperature hydrogen sensing with polyaniline/SnO2/Pd nanocomposites. Micro Nano Eng, 2021, 12, 100086 doi: 10.1016/j.mne.2021.100086
[24]
Tian J F, Yang G, Jiang D G, et al. A hybrid material consisting of bulk-reduced TiO2, graphene oxide and polyaniline for resistance based sensing of gaseous ammonia at room temperature. Microchim Acta, 2016, 183, 2871 doi: 10.1007/s00604-016-1912-6
[25]
Kumar R, Yadav B C. Fabrication of polyaniline (PANI)—tungsten oxide (WO3) composite for humidity sensing application. J Inorg Organomet Polym Mater, 2016, 26, 1421 doi: 10.1007/s10904-016-0412-9
[26]
Mhamdi H, Zaghouani R B, Fiorido T, et al. Study of n-WO3/p-porous silicon structures for gas-sensing applications. J Mater Sci Mater Electron, 2020, 31, 7862 doi: 10.1007/s10854-020-03324-8
[27]
Chaudhary V, Kaur A. Enhanced room temperature sulfur dioxide sensing behaviour of in situ polymerized polyaniline–tungsten oxide nanocomposite possessing honeycomb morphology. RSC Adv, 2015, 5, 73535 doi: 10.1039/C5RA08275G
[28]
Wang Z H, Lan K B, Wang Z, et al. High-performance PANI sensor on silicon nanowire arrays for sub-ppb NH3 detection. Talanta, 2025, 282, 127086 doi: 10.1016/j.talanta.2024.127086
[29]
Jain A, Nabeel A N, Bhagwat S, et al. Fabrication of polypyrrole gas sensor for detection of NH3 using an oxidizing agent and pyrrole combinations: Studies and characterizations. Heliyon, 2023, 9, e17611 doi: 10.1016/j.heliyon.2023.e17611
[30]
Khuspe G D, Bandgar D K, Sen S, et al. Fussy nanofibrous network of polyaniline (PANi) for NH3 detection. Synth Met, 2012, 162, 1822 doi: 10.1016/j.synthmet.2012.08.022
[31]
Huang J, Yang T L, Kang Y F, et al. Gas sensing performance of polyaniline/ZnO organic-inorganic hybrids for detecting VOCs at low temperature. J Nat Gas Chem, 2011, 20, 515 doi: 10.1016/S1003-9953(10)60230-7
[32]
Fratoddi I, Venditti I, Cametti C, et al. Chemiresistive polyaniline-based gas sensors: A mini review. Sens Actuat B Chem, 2015, 220, 534 doi: 10.1016/j.snb.2015.05.107
[33]
Duong N H, Nguyen T T, Nguyen D T, et al. Effect of TiO2 on the gas sensing features of TiO2/PANi nanocomposites. Sensors, 2011, 11, 1924 doi: 10.3390/s110201924
[34]
Li S Q, Lin P F, Zhao L P, et al. The room temperature gas sensor based on Polyaniline@flower-like WO3 nanocomposites and flexible PET substrate for NH3 detection. Sens Actuat B Chem, 2017, 259, 505 doi: 10.1016/j.snb.2017.11.081
[35]
Lascu I, Locovei C, Bradu C, et al. Polyaniline-derived nitrogen-containing carbon nanostructures with different morphologies as anode modifier in microbial fuel cells. Int J Mol Sci, 2022, 23, 11230 doi: 10.3390/ijms231911230
[36]
Xu L J, Yin M L, Liu S F. Ag(x)@WO3 core-shell nanostructure for LSP enhanced chemical sensors. Sci Rep, 2014, 4, 6745 doi: 10.1038/srep06745
[37]
Challagulla S, Tarafder K, Ganesan R, et al. Structure sensitive photocatalytic reduction of nitroarenes over TiO2. Sci Rep, 2017, 7, 8783 doi: 10.1038/s41598-017-08599-2
[38]
Hardcastle F D. Raman spectroscopy of titania (TiO2) nanotubular water-splitting catalysts. Arkansas Academy Science, 2011, 65, 43 doi: 10.54119/jaas.2011.6504
[39]
Mousli F, Chaouchi A, Hocine S, et al. Diazonium-modified TiO2/polyaniline core/shell nanoparticles. Structural characterization, interfacial aspects and photocatalytic performances. Appl Surf Sci, 2019, 465, 1078 doi: 10.1016/j.apsusc.2018.09.252
[40]
Pakdel H, Galstyan V, D’Arco A, et al. Synthesis of WO3 nanopowder using a green surfactant for efficient gas sensing applications. Ceram Int, 2023, 49, 30501 doi: 10.1016/j.ceramint.2023.06.314
[41]
Aldrees A, Khan H, Alzahrani A, et al. Synthesis and characterization of tungsten trioxide (WO3) as photocatalyst against wastewater pollutants. Appl Water Sci, 2023, 13, 156 doi: 10.1007/s13201-023-01938-x
[42]
Ishida Y, Motono S, Doshin W, et al. Small nanosized oxygen-deficient tungsten oxide particles: Mechanistic investigation with controlled plasma generation in water for their preparation. ACS Omega, 2017, 2, 5104 doi: 10.1021/acsomega.7b00986
[43]
Fewster P. Reciprocal space mapping. Crit Rev Solid State Mater Sci, 1996, 22, 269 doi: 10.1080/10408439708241259
[44]
Stanchu H V, Kuchuk A V, Barchuk M, et al. Asymmetrical reciprocal space mapping using X-ray diffraction: A technique for structural characterization of GaN/AlN superlattices. Cryst Eng Comm, 2017, 19, 2977 doi: 10.1039/C7CE00584A
[45]
Tai H L, Wang S, Duan Z H, et al. Evolution of breath analysis based on humidity and gas sensors: Potential and challenges. Sens Actuat B Chem, 2020, 318, 128104 doi: 10.1016/j.snb.2020.128104
[46]
Ates H C, Dincer C. Wearable breath analysis. Nat Rev Bioeng, 2023, 1, 80 doi: 10.1038/s44222-022-00011-7
[47]
Fakhri E, Plugaru R, Sultan M T, et al. Piezoresistance characterization of silicon nanowires in uniaxial and isostatic pressure variation. Sensors, 2022, 22, 6340 doi: 10.3390/s22176340
[48]
Zhang S S, Lou L, Lee C K. Piezoresistive silicon nanowire based nanoelectromechanical system cantilever air flow sensor. Appl Phys Lett, 2012, 100, 023111 doi: 10.1063/1.3675878
[49]
Kim C, Ahn H, Ji T. Flexible pressure sensors based on silicon nanowire array built by metal-assisted chemical etching. IEEE Electron Device Lett, 2020, 41, 1233 doi: 10.1109/LED.2020.3001977
[50]
Ghosh R, Song M S, Park J, et al. Fabrication of piezoresistive Si nanorod-based pressure sensor arrays: A promising candidate for portable breath monitoring devices. Nano Energy, 2021, 80, 105537 doi: 10.1016/j.nanoen.2020.105537
[51]
Song Y H, Shu C, Song Z H, et al. Self-powered health monitoring with ultrafast response and recovery enabled by nanostructured silicon moisture-electric generator. Chem Eng J, 2023, 468, 143797 doi: 10.1016/j.cej.2023.143797
[52]
Qin Y X, Jiang Y Q, Zhao L M. Modulation of agglomeration of vertical porous silicon nanowires and the effect on gas-sensing response. Adv Eng Mater, 2018, 20, 1700893 doi: 10.1002/adem.201700893
[53]
Morganti D, Leonardi A A, Lo Faro M J, et al. Ultrathin silicon nanowires for optical and electrical nitrogen dioxide detection. Nanomaterials, 2021, 11, 1767 doi: 10.3390/nano11071767
[54]
Park S B, Khattar D. Tachypnea. Emerg Office Pediatr, 2024, 8, 33
[55]
Lou C G, Hou K X, Zhu W T, et al. Human respiratory monitoring based on Schottky resistance humidity sensors. Materials, 2020, 13, 430 doi: 10.3390/ma13020430
[56]
Kundu S, Majumder R, Ghosh R, et al. Relative humidity sensing properties of doped polyaniline-encased multiwall carbon nanotubes: Wearable and flexible human respiration monitoring application. J Mater Sci, 2020, 55, 3884 doi: 10.1007/s10853-019-04276-z
[57]
Ekande O S, Kumar M. Review on polyaniline as reductive photocatalyst for the construction of the visible light active heterojunction for the generation of reactive oxygen species. J Environ Chem Eng, 2021, 9, 105725 doi: 10.1016/j.jece.2021.105725
[58]
Xie H, Li N, Chen X Z, et al. Surface oxygen vacancies promoted photodegradation of benzene on TiO2 film. Appl Surf Sci, 2020, 511, 145597 doi: 10.1016/j.apsusc.2020.145597
[59]
Chen H, Liu Y, Xie C S, et al. A comparative study on UV light activated porous TiO2 and ZnO film sensors for gas sensing at room temperature. Ceram Int, 2012, 38, 503 doi: 10.1016/j.ceramint.2011.07.035
[60]
Rahman K H, Kar A K. Effect of band gap variation and sensitization process of polyaniline (PANI)-TiO2 p−n heterojunction photocatalysts on the enhancement of photocatalytic degradation of toxic methylene blue with UV irradiation. J Environ Chem Eng, 2020, 8, 104181 doi: 10.1016/j.jece.2020.104181
[61]
Nunes D, Fortunato E, Martins R. Flexible nanostructured TiO2-based gas and UV sensors: A review. Discov Mater, 2022, 2, 2 doi: 10.1007/s43939-022-00023-5
[62]
Liu D, Lin L M, Chen Q F, et al. Low power consumption gas sensor created from silicon nanowires/TiO2 core–shell heterojunctions. ACS Sens, 2017, 2, 1491 doi: 10.1021/acssensors.7b00459
[63]
Qin Y X, Wang Z F, Liu D, et al. Dendritic composite array of silicon nanowires/WO3 nanowires for sensitive detection of NO2 at room temperature. Mater Lett, 2017, 207, 29 doi: 10.1016/j.matlet.2017.07.042
[64]
Staerz A, Weimar U, Barsan N. Understanding the potential of WO3 based sensors for breath analysis. Sensors, 2016, 16, 1815 doi: 10.3390/s16111815
[65]
Kim S J, Choi S J, Jang J S, et al. Mesoporous WO3 nanofibers with protein-templated nanoscale catalysts for detection of trace biomarkers in exhaled breath. ACS Nano, 2016, 10, 5891 doi: 10.1021/acsnano.6b01196
[66]
Xu M T, Wang Y J, Chen F C, et al. Breathable Nanomesh pressure sensor with layered polyaniline grown at gas-liquid interface. Chem Eng J, 2022, 445, 136717 doi: 10.1016/j.cej.2022.136717
[67]
Wang X W, Zhang D Z, Zhang H B, et al. In situ polymerized polyaniline/MXene (V2C) as building blocks of supercapacitor and ammonia sensor self-powered by electromagnetic-triboelectric hybrid generator. Nano Energy, 2021, 88, 106242 doi: 10.1016/j.nanoen.2021.106242
[68]
Beygisangchin M, Hossein Baghdadi A, Kartom Kamarudin S, et al. Recent progress in polyaniline and its composites; Synthesis, properties, and applications. Eur Polym J, 2024, 210, 112948 doi: 10.1016/j.eurpolymj.2024.112948
[69]
Han B, Popov A L, Shekunova T O, et al. Highly crystalline WO3 nanoparticles are nontoxic to stem cells and cancer cells. J Nanomater, 2019, 5384132 doi: 10.1155/2019/5384132

24090035Supporting_information.pdf

    • Search

    Advanced Search >>

    GET CITATION

    shu

    Export: BibTex EndNote

    Article Metrics

    Article views: 298 Times PDF downloads: 36 Times Cited by: 0 Times

    History

    Received: 18 September 2024 Revised: 06 November 2024 Online: Accepted Manuscript: 29 November 2024Uncorrected proof: 06 February 2025Published: 14 March 2025

    Catalog

      Email This Article

      User name:
      Email:*请输入正确邮箱
      Code:*验证码错误
      Send
      Article Navigation >  Journal of Semiconductors  > 2025  >  46(3): 032101
      Muhammad Taha Sultan, Anca Dumitru, Elham Fakhri, Rachel Brophy, Snorri Thorgeir Ingvarsson, Andrei Manolescu, Halldor Gudfinur Svavarsson. Fabrication and application of SiNWs based PANI:MOx heterostructures for human respiratory monitoring[J]. Journal of Semiconductors, 2025, 46(3): 032101. doi: 10.1088/1674-4926/24090035 ****M T Sultan, A Dumitru, E Fakhri, R Brophy, S T Ingvarsson, A Manolescu, and H G Svavarsson, Fabrication and application of SiNWs based PANI:MOx heterostructures for human respiratory monitoring[J]. J. Semicond., 2025, 46(3), 032101 doi: 10.1088/1674-4926/24090035
      Citation:
      Muhammad Taha Sultan, Anca Dumitru, Elham Fakhri, Rachel Brophy, Snorri Thorgeir Ingvarsson, Andrei Manolescu, Halldor Gudfinur Svavarsson. Fabrication and application of SiNWs based PANI:MOx heterostructures for human respiratory monitoring[J]. Journal of Semiconductors, 2025, 46(3): 032101. doi: 10.1088/1674-4926/24090035 ****
      M T Sultan, A Dumitru, E Fakhri, R Brophy, S T Ingvarsson, A Manolescu, and H G Svavarsson, Fabrication and application of SiNWs based PANI:MOx heterostructures for human respiratory monitoring[J]. J. Semicond., 2025, 46(3), 032101 doi: 10.1088/1674-4926/24090035
      shu

      Fabrication and application of SiNWs based PANI:MOx heterostructures for human respiratory monitoring

      DOI: 10.1088/1674-4926/24090035
      CSTR: 32376.14.1674-4926.24090035
      • 1.

        Reykjavik University, Department of Engineering, Menntavegur 1, 101, Reykjavik, Iceland

      • 2.

        University of Bucharest, Faculty of Physics, PO Box MG-11, 077125, Magurele, Romania

      • 3.

        University of Iceland, Saemundargata 2, 102 Reykjavík, Iceland

      More Information
      • Muhammad Taha Sultan is a research specialist at Reykjavik Univeristy. He received his MSc. in Materials Science from CAU University Kiel, Germany and Ph.D. in Applied Physics in 2019 from Reykjavik University, Iceland. His research interest is in field of thin-films and nanotechnology along with their application in devices such as sensor, photovoltaics, photodetectors, magnetism and smart windows
      • Halldor Gudfinur Svavarsson：Halldor Gudfinnur Svavarsson is a professor at Reykjavik University. He has a B.Sc. degree in chemistry from University of Iceland and an M.Sc. degree in mat. Science Eng. from the Technological University of Tampere, Finland. In 2003, he graduated with a Ph.D. degree in physics from the University of Iceland. His main research interest is in the field of silicon nano-nanostructures for sensing applications
      • Corresponding author: muhammads@ru.is
      • Received Date: 2024-09-18
      • Revised Date: 2024-11-06
        • Available Online: 2024-11-29

      Catalog

        Journal of Semiconductors © 2017 All Rights Reserved   京ICP备05085259号-2

        /

        DownLoad:  Full-Size Img  PowerPoint
        Return
        Return