An Electrochemical Wind Velocity Sensor - Analytical Chemistry (ACS

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An Electrochemical Wind Velocity Sensor siddhi khaire, Pramod Gaikwad, Mruthyunjayachari Chattanahalli Devendrachari, Alagar Raja Kottaichamy, Zahid Manzoor Bhat, Swapnil Varhade, Shahid Pottachola Shafi, Ravikumar Thimmappa, and Musthafa Ottakam Thotiyl Anal. Chem., Just Accepted Manuscript • DOI: 10.1021/acs.analchem.7b04841 • Publication Date (Web): 13 Mar 2018 Downloaded from http://pubs.acs.org on March 16, 2018

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Analytical Chemistry

An Electrochemical Wind Velocity Sensor Siddhi Khaire, Pramod Gaikwad, Mruthyunjayachari Chattanahalli Devendrachari, Alagar Raja Kottaichamy, Zahid Manzoor Bhat, Swapnil Varhade, Shahid Pottachola Shafi, Ravikumar Thimmappa, Musthafa Ottakam Thotiyl* Department of Chemistry and Centre for Energy Science, Indian Institute of Science Education and Research (IISER) Pune, Dr. Homi Bhabha Road, Pashan, Pune-411008, India. *Correspondence: [email protected] ABSTRACT: Electrochemical interfaces invariably generate unipolar electromotive force due to unidirectional nature of electrochemical double layers. Herein we show an unprecedented generation of a time varying bipolar electric field between identical half-cell electrodes induced by tailored interfacial migration of magnetic particles. The periodic oscillation of bipolar electric field is monotonically correlated with velocity dependent torque, opening new electrochemical pathways targeting velocity monitoring systems.

State of the art electrochemical energy storage and conversion devices such as batteries, fuel cells, supercapacitors and solar cells generate always unipolar electromotive force (EMF), and so far no attempt has been made to generate alternating EMF signals in electrochemical systems.1-12 Here we have designed a concentration type electrochemical cell containing magnetic particles for the generation of alternating voltage with decent frequency response and its direct applicability as an electrochemical anemometer to measure wind velocity. Anemometers are widely used around the world for measuring the wind speed and it has little evolved since its invention in 15th century.13-15 The mechanical anemometers consist of 3 to 4 hemispherical cups held at the end of horizontal arms and the overall assembly is glued on a vertical shaft.13-15 The hemispherical cups move at a rate proportional to the wind speed and counting the rotations per minute of any hemispherical cup over a time period measures the wind speed.13-15 By measuring the periodically oscillating electromotive force (EMF) between two identical half-cell electrodes housed in a cell containing magnetic particles, we demonstrate the proof of concept of an electrochemical anemometer which can measure the wind velocity. We have designed a concentration type electrochemical cell containing magnetic particles for constructing an anemometer. As shown in Scheme 1, the electrochemical cell contains two identical Cu electrodes and magnetic particles are suspended in the electrolyte. The rotation of an external permanent magnet around the electrodes brings in a concentration gradient of magnetic particles on respective electrodes with a net voltage difference between the electrodes, Scheme 1, attenuating the EMF periodically between positive and negative phase over a time period.

Scheme 1. Schematics of electrochemical interface generating periodically oscillating electromotive force and its applicability as wind speed measuring system or anemometer EXPERIMENTAL SECTION Materials and methods Ferric (II) chloride terahydrate, iron particles, anhydrous ferric (III) chloride, HCl, H2SO4, 3-amino benzoic acid, ammonium per sulphate, ammonium hydroxide, and aniline were of analytical grade and were procured from Alfa Aesar, India. Cu foil of thickness 0.1mm was purchased from Sigma Aldrich. Aniline was distilled prior to the synthesis of copolymer covered magnetic particles. Synthesis of magnetic particles γ-Fe3O4 was synthesized by co-precipitation method.16-18 Accurately weighed quantity (2.4g) of anhydrous FeCl3 was dissolved in 50ml of distilled water, and separately 1.98g FeCl2 tetrahydrate (0.016mol) was dissolved in 50ml distilled. Both the solutions were sonicated to get clear solution. After

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sonication both the solutions were mixed with vigorous stirring. To the above reaction mixture ammonium hydroxide solution was gradually added until the reaction mixture attains pH=12 with the formation of dark brown precipitate. The reaction mixture was stirred vigorously at 50oC for about 30 minutes, and followed by sonication for about 1 hour. Then the reaction mixture was stirred continuously at 80oC for about 3 hours. Finally the obtained Fe3O4 particles were collected using a magnet and washed thoroughly with acetone for several times and kept for drying in a hot air oven at 60oC for 24 hours.

Dynamic Light Scattering technique using the Malvern Zetasizer Nano ZS 90 machine. Device fabrication and operation of Electrochemical Anemometer The setup consists of a cell equipped with identical Cu electrodes and magnetic particles are suspended in the electrolyte. The cell is held stationary on the shaft attached to a fan by means of a bearing. A 0.5T magnet is mounted on the fan which rotates with the wind. When the magnet is close to one of the electrodes, a concentration gradient is developed and the particles converge at one of the electrodes. As a result, the properties of that electrode get modified and a voltage develops across the cell. When the magnet moves with the fan to the other electrode, the concentration gradient reverses and a voltage of the opposite polarity is generated across the cell. As the magnet rotates along with the fan around the stationary cell due to wind velocity, the concentration gradient of the magnetic particles in the electrolyte is modulated in accordance with the position of the magnet. Thus a time varying bipolar signal whose frequency is dependent on the wind velocity that rotates the fan is achieved across the cell. This output is given to a signal conditioning circuit based on an Arduino Uno board (Microcontroller Atmega328) for which the block diagram is given in Figure S1. An amplifier based comparator converts the bipolar alternating signal into a unipolar digital signal with amplitude of 5V peak to peak which is then given to the Arduino Uno. The Arduino counts incoming pulses and prints the RPM and corresponding wind speed on the 20*4 Alphanumeric Liquid Crystal Display. The sequence of the interrupt-based program is given in Figure S2.

Synthesis of 3-amino benzoic acid covered Fe3O4 Copolymer covered γ-Fe3O4 magnetic particles were synthesized as follows. γ-Fe3O4 was synthesized by coprecipitation method as detailed above. To the dark brown precipitate obtained after the addition of ammonium hydroxide, about 2.6g of 3- amino benzoic acid dissolved in alcohol was added drop wise with vigorous stirring. Then the reaction mixture was sonicated for 1 hour. After sonication the reaction mixture was stirred continuously at 80oC for about 3 hours. Finally the obtained 3-amino benzoic acid covered Fe3O4 particles were collected using a magnet and washed thoroughly with acetone for several times and kept for drying in a hot air oven at 60oC for 24 hours. Preparation of poly (aniline - co - 3 - amino benzoic acid) covered Fe3O4 Poly (aniline - co - 3 - amino benzoic acid) covered Fe3O4 were synthesized by copolymerizing aniline and 3-amino benzoic acid in 1:2 ratio.19,20 For the synthesis of copolymer accurately weighed 2.0g of 3-amino benzoic acid covered Fe3O4 magnetic particles were added to a 250ml round bottomed flask containing 80 ml 0.5 M HCl solution and dispersed well with stirring. To the same round bottomed flask, accurately weighed 1.0g of aniline was added and stirred well to get homogeneous mixture. Ice cold solution of ammonium persulphate (5.0 g in 10ml) was added drop wise to the above homogeneous reaction mixture. After 30 minutes of complete addition of ammonium persulphate solution the reaction mass changed its color to dark green color. The stirring was continued for about 24 hours at room temperature. After completion of reaction the obtained product was collected by filtration, and washed thoroughly with water and dried in vacuum oven at 60oC for about 24 hours.

RESULTS AND DISCUSSION By measuring the frequency of AC voltage across the electrodes, one can measure the rotations per minute (RPM) of the stage housing the magnet that in turn can be correlated with the wind speed (Scheme 1) if the stage is made to move in wind blow, Scheme 1. Magnetic particles were prepared as reported in the literature. XRD pattern (Figure S3a, Supporting Information) demonstrates the γ-Fe3O4 phase of iron oxide, JCPDS card number 79-0417. SEM with EDS (Figure S3b and S3c, Supporting Information) indicate nearly uniform particles and the presence of Fe and O as constituent elements. Magnetic hysteresis data, Figure S3d suggests superparamagnetic property of Fe3O4 because of near zero remanence and coercivity and the nanoparticles exhibiting superparamagnetic behavior have lower saturation magnetization values than the bulk Fe3O4 (~92 emu g−1).21,22,23 FTIR spectra (Figure S3e, Supporting Information) clearly show the presence of Fe-O stretching at ~600 cm-1 and -OH bending and stretching vibrations at ~1630 cm-1 and ~3450 cm-1 respectively.24,25 All these evidence the formation of magnetic γ-Fe3O4 phase of nanoparticles. The electrochemical cell was fabricated as explained in experimental section. The cell contained two identical Cu electrodes having identical area kept at a distance of ~1 cm. A permanent magnet of strength 0.5 Tesla is mounted on a rotating axial fan, Scheme 1. The voltage profile when the stage with a permanent magnet is rotated around the electrochemical cell without magnetic particles demonstrated a

Characterization % transmittance of the bare and copolymer covered magnetic γ-Fe3O4 particles before and after cycling in the electrochemical anemometer was measured using a Perkin Elmer Lambda 950 machine in the UV-Vis region. Morphology of both the particles before and after use was investigated by a JSM-5300LV (Japan) scanning electron microscope (SEM). Powder X-Ray Diffraction technique was used to analyze the bare and copolymer covered particles before and after use using Bruker D8 Advance machine. Magnetization measurements were carried out to establish that the particles are magnetic (super paramagnetic) and retain magnetism even after several cycles. The size range of fresh, cycled and stored magnetic particles was estimated by


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Figure 1. (a) Voltage obtained by rotating the magnet around the cell without magnetic particles and (b) the sudden rise in voltage when uncoated magnetic particles are added to the cell. The alternating voltage profile obtained for (c) uncoated particles and redox active conducting polymer coated particles on continuous rotation of the stage at 15 RPM and (d) for pure iron particles at 10 RPM.

conductivity of Fe3O4 particles. To improve the voltage amplitude, we have coated the magnetic particles with a redox active conducting polymer (see experimental section for more details), Figure S4a-f, Supporting Information. The large background signal in the cyclic voltammogram of magnetite particle after covering with conducting polymer, Figure S4e, reflects improved charge transport to and from the particle. The AC amplitude generated by the polymer coated magnetic particles clearly demonstrates significant improvements, Figure 1c. This could be due to improved interfacial electron transport and relatively faster establishment of the Nernstian equilibrium. By replacing magnetite particles with pure iron particles, we demonstrate that the AC output can be amplified 8 times with a peak to peak voltage of ~650 mV, and a peak power output of ~18 µW/cm2, Figure 1d (See also Figure S5). This preliminary result suggests that by tuning the physicochemical properties of the migrating particles, this device may offer additional opportunity such as AC energy storage

near zero voltage profile without any attenuation over time, Figure 1a. The zero electromotive force between the two

electrodes is due to the identicality of either electrodes and the absence of any concentration gradient at either electrode. On introducing magnetic particles into the solution and on rotating the stage, when the magnet is near electrode 1, Scheme 1, a sudden voltage jump was observed in the positive direction, Figure 1b.This is due to enhanced concentration gradient of magnetic particles on electrode 1 resulting in a net EMF between identical Cu electrodes. On the other hand, when the magnet is closer to electrode 2, the voltage grows in the negative direction owing to increased concentration gradient on this electrode, Scheme 1 and Figure 1b. The periodic attenuation between the positive and negative EMF can be seen on rotating the stage, Figure 1c demonstrating the generation of alternating voltage from electrochemical cells. The voltages in either direction were in the range of few millivolts which could be due to the lower electronic



Figure 2. (a) Dependence of cell voltage on the amount of particles, (b) stability of voltage with time when the magnet is permanently kept for a certain duration on either electrodes, (c) frequency dependency studies and (d) calibration curve for rpm obtained by the electrochemical system vs. a photogate reference.

amplitude is observed at higher particle content which could be attributed to similar distribution of particles on active electrode area beyond a certain particle density. Generated voltage demonstrated decent stability without significant decay over time when the magnet is permanently kept near either electrode for longer time duration, Figure 2b, suggesting decent stability of respective electrochemical interfaces. However there is a kind of memory effect as the voltage is seen to pick up from where it left off after the magnet is brought near electrode 1 again. We are yet to investigate this in depth but one of the possible reasons could be some surface changes taking place on the magnetite particles when they are brought near the electrodes. The frequency response of the electrochemical cell was then monitored by changing the RPM of the stage and then measuring the alternating voltage signals from the electrochemical cell. With increase in frequency of the stage, the voltage response from the cell decreased possibly due to lower time available in creating a

from wind energy. It should be noted that the plateau like behavior in Figure 1 near 0 V has more to do with cell architecture. The electrodes were fixed inside a cylindrical cell containing suspended magnetite particles (please refer experimental section). Due to the finite thickness of the electrodes, the particles first strike the edge of the electrode and then follow the magnet to the surface of the electrode. Hence, on both occasions when the voltage goes positive or negative, such a plateau effect is observed. The role of magnetic particles is only to alter the electrode potential of two identical half-cell electrodes one at a time in the presence of an external magnet, which is further confirmed by the EMF scaling up when the amount of magnetic particles are increased in the electrochemical cell, Figure 2a. This suggests that a net concentration of magnetic particles near the half-cell electrodes is responsible for the net EMF, reflecting the behavior of a concentration cell. Saturation in voltage


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Figure 3. (a) Response of the electrochemical anemometer during extended cycling, (b) peak to peak voltage output with respect to cycle number, (c) XRD pattern and (d) FTIR spectra for polymer covered Fe3O4 particles at various stages of cycling.

was also investigated by storing the magnetite particles in the electrolyte for 4 days and then performing physico-chemical characterization techniques such as Dynamic Light Scattering (DLS), FTIR and XRD. It was seen that the particles show minor agglomeration and there is no change in properties of the particles as the FTIR, XRD and DLS do not show any noticeable change or shift, Figures S7 and S8, Supporting Information. Magnetic hysteresis data show the superparamagnetic properties are maintained even after storage, Figure S9, Supporting Information. All these demonstrate extended cyclability and long term stability of magnetic particles in chosen electrolytes during the periodic migration between the half-cell electrodes, however we do not rule out the possibility of time dependent surface changes on the particles. Since the frequency of the voltage across the cell is a linear function of the frequency of the stage housing the magnet as demonstrated in Figure 2d, if the stage is kept in the path of wind blow, the electrochemical interface can be used as an electrochemical means for measuring wind speed. The modulation of concentration gradient when the stage is moved in wind blow leads to modulation of cell

concentration gradient at the interfaces, Figure 2c. However the frequency of bipolar voltage across the cell is scaled up linearly to the frequency of the stage measured by a photogate, Figure 2d, suggesting the setup can accurately measure the rotations per minute of the stage. This suggests that the system presented here has the potential to function as an anemometer to measure the wind speed if the stage is made to move in wind blow as demonstrated below. Extended cyclability is shown in Figure 3a,b and the system is cyclable for almost 1000 cycles at a selected frequency. It is seen that the voltage is retained ~75% after 1000 cycles. This could be due to some surface changes taking place on the magnetite particles during the migration between the electrodes. The stability of particles during different cycles was investigated by various physicochemical techniques. SEM with EDS did not demonstrate any noticeable agglomeration, Figure S6a-S6f, Supporting Information, during cycling. XRD patterns of magnetic particles during extended cycling did not reveal noticeable crystallographic changes, Figure 3b. FTIR spectra show the presence of Fe-O vibrations and –OH vibration even after extended cycling, Figure 3c. The long term storage stability



Figure 4. (a) Device assembly of electrochemical anemometer, (b) calibration curve for electrochemical anemometer vs. state of the art GM816 mini digital anemometer, (c) electrochemical anemometer output at constant wind speed (RPM is ∼ 54) and (d) signal conditioned output of electrochemical anemometer.

corresponding signal conditioned output demonstrate a stable and a reproducible response over cycling, Figure 4c, 4d, suggesting the stability of electrochemical interface. The accompanying video (Video S1) demonstrates the functioning of the device as an electrochemical means for measuring wind velocity.

voltage in the form an oscillating signal. This oscillating signal is processed using an Arduino Uno electronic board equipped with ATmega 318 microprocessor and the RPM of the fan is measured, Figure 4a. This is calibrated for wind speed using a state of the art anemometer (GM816 Mini Digital Anemometer) for reference. Thus it is found that the performance of the electrochemical anemometer is on par with state of the art electronic anemometers, Figure 4b. However, the theoretical resolution for the state of the art anemometer is 0.5 km/hr, while the electrochemical anemometer has a resolution of ~1 km/hr. The comparatively lower resolution is because of the fan specifications like weight, number of blades, size etc. For a smaller and lighter setup, the resolution can be improved. Nevertheless, the linear response observed clearly suggest that the electrochemical cell presented here can function as an anemometer and measure wind speed, Figure 4b. The device output at a constant wind speed and the

CONCULSION In essence, we have demonstrated the proof of concept of an electrochemical interface which can generate a periodically oscillating EMF induced by controlled migration of magnetic particles via an external magnetic field. The frequency of bipolar EMF showed a monotonic correlation with magnitude of the force causing it, opening new electrochemical means targeting velocity measurement systems.


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Analytical Chemistry (11) Larcher, D.; Tarascon, J.-M. Nat. Chem. 2014, 7 (1), 19. (12) Hassoun, J.; Lee, K. S.; Sun, Y. K.; Scrosati, B. J. Am. Chem. Soc. 2011, 133 (9), 3139-3143. (13) Fritschen, L. J. J. Appl. Meteorol. 1967, 6, 695–698. (14) Marvin, C. F. Mon. Weather Rev. 1932, 60, 43–56. (15) Carrion, S. P.; Cano, J. C.; Palmer, F. S. Sensors. 2014, 14, 21418-21452. (16) Mascolo, M. C.; Pei, Y.; Ring, T. Materials (Basel). 2013, 6. (17) Hariani, P.; Faizal, M.; Ridwan, R.; Marsi, M.; Setiabudidaya, D. Int. J. Environ. Sci. Dev. 2013, 4, 336. (18) Kulkarni, S. A.; Sawadh, P. S.; Kokate, K. K. IJCA Proc. Int. Conf. Benchmarks Eng. Sci. Technol. 2012 2012, ICBEST (2), 17. (19) Moghadam, P. N.; Khalafy, J.; Taheri, T. Polym. Adv. Technol. 2010, 21 (4), 235. (20) Nazarzadeh Zare, E.; Mansour Lakouraj, M.; Ramezani, A. New J. Chem. 2016, 40 (3), 2521. (21) Fattahi, H.; Arsalani, N.; Nazarpoor, M. eXPRESS Polym. Lett. 2010, 4, 329. (22) Mahdavi, M.; Ahmad, M.; Jelas Haron, M.; Namvar, F.; Nadi, B.; Zaki Ab Rahman, M.; Amin, J. Molecules 2013, 18, 7533. (23) Cornell, R. M.; Schwertmann, U. The iron oxides : structure, properties, reactions, occurrence, and uses; Weinheim ; New York : VCH, 1996. (24) Bordbar, A. K.; Rastegari, A. A.; Amiri, R.; Ranjbakhsh, E.; Abbasi, M.; Khosropour, A. R. Biotechnol. Res. Int. 2014, 2014, 1. (25) Lopez, J. A.; González, F.; Bonilla, F. A.; Zambrano, G.; Gómez, M. E. Rev. Latinoam. Metal. y Mater. 2010, 30 (60), 60.

ASSOCIATED CONTENT Supporting Information The supporting information contains characterization of magnetic nanoparticles before and after extended cycling, block diagram and flow chart of the electrochemical wind velocity monitoring system. The Supporting Information is available free of charge on the ACS Publications website.

AUTHOR INFORMATION Corresponding Author Corresponding Author: Musthafa Ottakam Thotiyl, Department of Chemistry and Centre for Energy Science, Indian Institute of Science Education and Research (IISER) Pune,Dr. Homi Bhabha Road, Pashan, Pune-411008, India. E-mail: [email protected]

Author Contributions SK carried out the experiments related to the electrochemical anemometer. PG contributed towards development of the setup and experiments related to the electrochemical anemometer. MCD synthesized and characterized the magnetic nanoparticles. ARK, ZMB, SV, SPS and RK carried out extended cycling of the electrochemical anemometer. MOT wrote the manuscript. All authors have participated in the interpretation of the results of the manuscript.

ACKNOWLEDGMENT MOT acknowledges DST-SERB, MHRD fast track, and DST Nanomission for financial assistance.

REFERENCES (1) Mourad, E.; Coustan, L.; Lannelongue, P.; Zigah, D.; Mehdi, A.; Vioux, A.; Freunberger, S. A.; Favier, F.; Fontaine, O. Nat. Mat. 2016, 16, 446. (2) Mahne, N.; Schafzahl, B.; Leypold, C.; Leypold, M.; Grumm, S.; Leitgeb, A.; Strohmeier, G. A.; Wilkening, M.; Fontaine, O.; Kramer, D.; Slugovc, C.; Borisov, S. M.; Freunberger, S. A. Nat. Energy 2017, 2 (5), 17036. (3) Gonzalez-Pedro, V.; Juarez-Perez, E. J.; Arsyad, W.-S.; Barea, E. M.; Fabregat-Santiago, F.; Mora-Sero, I.; Bisquert, J. Nano Lett. 2014, 14 (2), 888. (4) Yan, Y.; Gunzelmann, D.; Pozo-Gonzalo, C.; F. Hollenkamp, A.; Howlett, P.; R. MacFarlane, D.; Forsyth, M. Electrochim. Acta 2017, 235. (5) Cavaliere, S.; Subianto, S.; Savych, I.; Tillard, M.; J. Jones, D.; Rozière, J. J. Phys. Chem. C 2013, 117, 18298. (6) Li, L.; Chen, L.; Mukherjee, S.; Gao, J.; Sun, H.; Liu, Z.; Ma, X.; Gupta, T.; Singh, C. V.; Ren, W.; Cheng, H. M.; Koratkar, N. Adv. Mater. 2017, 29 (7) Ravikumar; Scott, K. Chem. Commun. 2012, 48 (45), 5584-5586 (8) Reddy, M. V; Rao, G. V. S.; Chowdari, B. V. R. Chem. Rev. 2013, 113, 5364−5457. (9) Gao, W.; Singh, N.; Song, L.; Liu, Z.; Arava, L.; Ci, L.; Vajtai, R.; Zhang, Q.; Wei, B.; M Ajayan, P. Nat. Nanotechnol. 2011, 6, 496. (10) Miroshnikov, M.; Divya, K. P.; Babu, G.; Meiyazhagan, A.; Arava, L. M. R.; Ajayan, P. M.; John, G. J. Mater. Chem. A 2016, 4, 12370.



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