A Study on the sensitivity and selectivity properties of Polymer based gas-vapor sensors

Abstract

In this study, the water soluble poly (diphenylamine sulfonic acid) (PSDA) and the diblock copolymer of PSDA with poly(ethylene glycol) (PEG) were used to construct the interdigitated film electrodes (IDEs). Their responses against humidity and various solvent vapors were investigated by impedance measurements. Sorption and desorption behaviors of the solvents were determined by simultaneous registration of the impedance (Z) and the resistive (R, resistance) and capacitive (X, reactance) components of the Z under different potential bias and alternating current (ac) frequencies. The sensor responses were discussed considering the polar/non-polar and polarizability properties of the polymers and solvents. The effect of ac frequency and potential bias on the sensitivity and selectivity of the sensors were discussed.  It was found that the solvent polarity is the primary effect on the electrical conductance and capacitance of both PSDA homo polymer and PSDA-b-PEG block copolymer. The results supported that the dipolarity-polarizability properties of solvents have also a critical role on sensor response at low ac frequencies. The more polarizable solvents gave higher sensor responses at lower ac frequencies. The equilibrium response of the PSDA based sensor was correlated with the dielectric constant of the solvents. The values of Z and R of PSDA film under saturated solvent vapors at 1 kHz ac frequency were linearly correlated (R² was 0.955, 0.993 and 0.957 for Z, R and X, respectively, in semi-logarithmic scale) with the values of the dielectric constants of the solvents, except water. A similar correlation (R²= 0.996) was obtained by using the R values of the PSDA film at 100 kHz ac frequency. In the case of PSDA-b-PEG polymer film, it was also possible to establish an almost linear correlation (R²=0.943) between the R at 100 kHz ac frequency and the values of the dielectric constants of the solvents, except acetone and water. Consequently, it was found that the applied ac frequency was distinctive on both the sensitivity and selectivity of the studied sensor. 

References

1. Mayer U, A semiempirical model for the description of solvent effects on chemical reactions, Pure Appl. Chem. 1979; 51: 1697-1712.
2. Shevade AV, Ryan MA, Homer ML, Manfreda AM, Zhou H, Manatt KS, Molecular modelling of polymer composite–analyte interactions in electronic nose sensors, Sens. Actuators B. 2003 Sep; 93: 84-91. DOI: 10.1016/S0925-4005(03)00245-4.
3. Li JR, Xu JR, Zhang MQ, Rong MZ, Carbon black/polystyrene composites as candidates for gas sensing materials, Carbon. 2003 Dec; 41 (12): 2353-60. DOI: 10.1016/S0008-6223(03)00273-2.
4. Bouvree A, Feller JF, Castro M, Grohens Y, Rinaudo M, Conductive Polymer nano-bio Composites (CPC): Chitosan-carbon nanoparticle a good candidate to design polar vapor sensors, Sensors and Actuators B. 2009 Apr; 138 (1): 138-47. DOI: 10.1016/j.snb.2009.02.022.
5. Zeng W, Zhang MQ, Rong MZ, Zheng G, Conductive polymer composites as gas sensors with size-related molecular discrimination capability, Sensors and Actuators B. 2007 Jun; 124: 118-26. DOI: 10.1016/j.snb.2006.12.021.
6. Vercelli B, Zecchin S, Comisso N, Zotti G, Berlin A, Dalcanale E, Groenendaal LB, Solvoconductivity of polyconjugated polymers: the roles of polymer oxidation degree and solvent electrical permittivity, Chem. Mater. 2002 Oct; 14 (11): 4768-74. DOI: 10.1021/cm0205938.
7. Chen SG, Hu JW, Zhang MQ, Rong MZ, Effects of temperature and vapor pressure on the gas sensing behavior of carbon black filled polyurethane composites, Sensors and Actuators B. 2005 Mar; 105 (2): 187-93. DOI: 10.1016/j.snb.2004.05.060.
8. Hu JW, Cheng GS, Zhang MQ, Li MW, Xiao DS, Chen SG, Rong MZ, Zheng Q, Electrical Response of Poly(ethylene Oxide)-Based Conductive Composites to Organic Vapors: Effect of Filler Content, Vapor Species, and Temperature, Journal of Applied Polymer Science. 2005 Nov; 98 (4): 1517-23. DOI: 10.1002/app.21973.

9. Cakar F, Moroglu MR, Cankurtaran H, Karaman F, Conducting poly(ether imide)–graphite composite for some solvent vapors sensing application, Sensors and Actuators B. 2010 Mar; 145 (1): 126-32. DOI: 10.1016/j.snb.2009.11.045.
10. Izutsu K, Electrochemistry in Nonaqueous Solutions, Part One: Fundamentals of Chemistry in Nonaqueous Solutions. Weinheim: WILEY-VCH; 2009. P. 10. ISBN: 978-3-527-32390-6.
11. Kamlet MJ, Taft RW, Linear Solvation Energy Relationships. Local Empirical Rules or Fundamental Laws of Chemistry? A reply to Chemometricians. Acta Chem. Scand. 1985 Jan; B39: 611-28. DOI: 10.3891/acta.chem.scand.39b-0611.
12. Hierlemann A, Zellers ET, Ricco AJ, Use of linear salvation energy relationships for modeling responses from polymer-coated acoustic-wave vapor sensors, Anal. Chem. 2001 Jun; 73 (14): 3458-66. DOI: 10.1021/ac010083h.
13. Chen J, Tsubokawa N, Novel Gas Sensor from Polymer-Grafted Carbon Black: Vapor Response of Electric R of Conducting Composites Prepared from Poly(ethylene-block-ethylene oxide)-Grafted Carbon Black, J. Appl. Poly. Sci. 2000 Sep; 77 (11): 2437-47. DOI: 10.1002/1097-4628(20000912)77:11<2437::AID-APP12>3.0.CO;2-F.
14. Dong XM, Fu RW, Zhang MQ, Zhang B, Rong MZ, Electrical R response of carbon black filled amorphous polymer composite sensors to organic vapors at low vapor concentrations, Carbon. 2004 Jan; 42 (12-13): 2551-59. DOI:10.1016/j.carbon.2004.05.034.
15. Sun A, Li Z, Wei T, Li Y, Cui P, Highly sensitive humidity sensor at low humidity based on the quaternized polypyrrole composite film, Sensors and Actuators B. 2009 Oct; 142 (1): 197-203. DOI: 10.1016/j.snb.2009.08.028.
16. Cankurtaran H, Yazici O, Dinc S, Karaman F, Humidity Sensitive Properties of Electronically Conductive Poly(diphenylamine sulfonic acid) and Its Block Copolymer and Blends, Int. J. Electrochem. Sci. 2013 Mar; 8 (3): 3265-78. URL:http://www.electrochemsci.org/papers/vol8/80303265.pdf
17. Zor ŞD, Cankurtaran H, Impedimetric Humidity Sensor Based on Nanohybrid Composite of Conducting Poly(diphenylamine sulfonic acid), Journal of Sensors. 2016; Article ID 5479092, 9 pages http://dx.doi.org/10.1155/2016/5479092.
18. Lee CW, SW J, Gong MS, Polymeric humidity sensor using polyelectrolytes derived from alkoxysilane cross-linker, Sensors Actuators B. 2005 Mar; 105 (2): 150-58. DOI: 10.1016/j.snb.2004.05.037.
19. Casalini R, Kilitziraki D, Wood D, Petty M, Sensitivity of the electrical admittance of a polysiloxane film to organic vapours, Sensors and Actuators B. 1999 Jul; 56 (1): 37-44. DOI: 10.1016/S0925-4005(99)00039-8.
20. Harrey PM, Ramsey BJ, Evans PSA, Harrison DJ, Capacitive-type humidity sensors fabricated using the offset lithographic printing process, Sensors and Actuators B. 2002 Dec; 87 (2): 226-32. DOI: 10.1016/S0925-4005(02)00240-X.
21. Kim JH, Hong SM, Moon BM, Kim K, High-performance capacitive humidity sensor with novel electrode and polyimide layer based on MEMS technology, Microsystem Technologies Micro and Nanosystems Information Storage and Processing Systems. 2010 Dec; 16 (12): 2017-21. DOI: 10.1007/s00542-010-1139-0.
22. Lee MJ, Min NK, Yoo KP, Microhotplate-based high-speed polyimide capacitive humidity sensors, Sensor Letters. 2009 Aug; 7 (4): 517-22. DOI: 10.1166/sl.2009.1102.
23. Wang Y, Park S, Yeow JTW,, Langner A, Müller F, A capacitive humidity sensor based on ordered macroporous silicon with thin film surface coating, Sensors and Actuators B. 2010 Aug; 149 (1): 136-42. DOI:10.1016/j.snb.2010.06.010.
24. Oikonomou P, Manoli K, Goustouridis D, Raptis I, Sanopoulou M, Polymer/BaTiO3 nanocomposites based chemocapacitive sensors, Microelectronic Engineering. 2009 Apr; 86 (4): 1286-8. DOI: 10.1016/j.mee.2008.11.081.
25. Bearzotti A, Fratoddi I, Palummo L, Petrocco S, Furlani A, Lo Sterzo C, Russo MV, Highly ethynylated polymers: synthesis and applications for humidity sensors, Sensors and Actuators B. 2001 Jun; 76 (1-3): 316-21. DOI: 10.1016/S0925-4005(01)00607-4.
26. Mohr GJ, Spichiger-Keller UE, Development of an optical membrane for humidity, Microchim. Acta. 1998 Mar; 130 (1-2): 29-34. DOI: 10.1007/BF01254587.
27. Sakai Y, Sadaoka Y, Matsuguchi M, Humidity sensors based on polymer thin films, Sensors and Actuators B. 1996 Sep; 35 (1-3): 85-90. DOI: 10.1016/S0925-4005(96)02019-9.
28. Hua FJ, Ruckenstein E, Synthesis of a water-soluble diblock copolymer of polysulfonic diphenyl aniline and poly(ethylene oxide), J. Poly. Sci., Part A: Polymer Chemistry. 2004 May; 42 (9): 2179-91. DOI: 10.1002/pola.20042.
29. Schmidt JW, Moldover MR, Dielectric Permittivity of Eight Gases Measured with Cross Capacitors, Int. J. Thermophys. 2003 Feb; 24 (2): 375-403. DOI: 10.1023/A:1022963720063.
30. Gong MS, Kim JU, Kim JG, Preparation of water durable humidity sensor by attachment of polyelectrolyte membrane to electrode substrate by photochemical crosslinking reaction, Sensors and Actuators B. 2010 Jun; 147 (2): 539-47. DOI: 10.1016/j.snb.2010.04.017.
31. Anderson JH, Parks GA, Electrical Conductivity of Silica Gel in the Presence of Adsorbed Water, The Journal of Physical Chemistry. 1968 Oct; 72 (10): 3662-68. DOI: 10.1021/j100856a051.
32. Abboud JLM, Notario R, Critical compilation of scales of solvent parameters. Part I. Pure, non-hydrogen bond donor solvents, Pure Appl. Chem. 1999 Jan; 71 (4): 645-718. DOI: 10.1351/pac199971040645.
33. Stuart BH, Williams DR, A study of the absorption of chlorinated organic solvents by poly(ether ether ketone) using vibrational spectroscopy, Polymer. 1995 Oct; 36 (22): 4209-13. DOI: 10.1016/0032-3861(95)92215-Z.