Cerium Oxide Nanocomposite

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ScienceDirect Materials Today: Proceedings 8 (2019) 223–230

www.materialstoday.com/proceedings

ICMEE 2018

Synthesis, Structural, Morphological and Optical Characterization of Polyaniline hydrochloride/Cerium Oxide Nanocomposite J .Vidyaa,* and P.Balamurugana a,*

PG and Research Department of Physics,Government Arts College (Men), Nandanam,Chennai-600035,India.

Abstract

Polyaniline hydrochloride/cerium oxide nanocomposite has been prepared by in-situ polymerization technique. Field emission scanning electron microscopy confirms the morphology of the nanocomposite was spherical with diameter around 80nm. The X-ray diffraction, optical spectra, thermal analysis and EDAX spectra confirm the interaction between polyaniline hydrochloride and CeO2 nanoparticles. TG analysis reveals that a polyaniline hydrochloride/CeO2 nanocomposite has good thermal stability. The specific surface area of spherical nanostructure was found to be 21.39m2/g, pore volume is 0.080164cm3/g, and average pore radius was 14.5 nm. © 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the Materials For Energy and Environment. Keywords: Polymerization; Polyaniline hydrochloride; Cerium oxide; Composite; nanostructure.

1. Introduction Nanocomposites formed from metal oxides and intrinsically conducting polymer provides new insights because of their distinctive electrical, thermal, electrochemical, structural, optical and electro catalytic properties [1-7]. Conducting polymers performance was improved by the introduction of metal oxide on its polymer matrix. The nano size of conducting polymer with metal oxide nanocomposite materials find many industrial applications such as waste water purification, electrical circuits, super capacitors, solar cells and electromagnetic wave absorption [8-

* Corresponding author. Tel.: +91-960-028-6100 E-mail address: [email protected] 2214-7853 © 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the Materials For Energy and Environment.

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13]. Among all kinds of conducting polymers and its derivatives are widely used in many technical applications because of their unique proton dupability, low cast, easy polymerization, good conductivity, variable oxidation state, chemical stability [14-15]. Presently cerium dioxide nanoparticles have been used in many applications, since its electro catalytic behavior, optical transparency and oxygen storage capacity [16-18]. In this paper, the structural, morphology, adsorption & desorption isotherm and optical properties of polyaniline hydrochloride/cerium oxide nanocomposite were discussed. 2. Experimental 2.1. Materials Ceriumnitrate, Aniline, Ammoniumperoxydisulfide and Hydrochloricacid. All chemicals were analytical grade. Double distilled water was used for preparation of various solutions. 2.2. Synthesis of Polyaniline hydrochloride/Cerium oxide The nanocomposite of polyaniline hydrochloride/cerium oxide was prepared by the in-situ polymerization method. The cerium oxide nanoparticles prepared by chemical precipitation method was dispersed in 25 ml of 1M hydrochloric acid and then it was added with 0.1M aniline dispersed in 100 ml of aqueous 1M HCl by vigorous stirring at 5ºC for half an hour. After that APS (0.25 mol) was dissolved in 1M HCl and dropped into the reactor. After dropping the initiator, the reaction mixture was kept constant stirring for 24 h. When the reaction was finished, the dark green precipitate resulting from the polymerization reaction was filtered and washed with distilled water and acetone sequentially in order to remove the excess initiator, monomer, and oligomer. This precipitate is then dried in an oven at 60Cº for 24h. 3. Result and Discussions 3.1. Structural Analysis

Fig .3.1. XRD spectra of polyaniline hydrochloride/Cerium oxide Nanocomposite

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Figure.3.1. shows the X-ray diffraction Spectra of polyaniline hydrochloride/cerium oxide nanocomposite. The polyaniline hydrochloride/cerium oxide composite shows the sharp crystalline peaks at 15°, 20° and 25° corresponding to (011), (020) and (200) planes of polyaniline hydrochloride [4,18]. This spectra also shows sharp peaks at 28˚, 33˚, 47˚, 56˚, 60˚ and 69˚ corresponding to (111), (200), (220), (311), (222) and (400) planes of face centered cubic (fcc) fluorite structure of cerium oxide and were in concurrence with JCPDS 81-0792 [19]. This structural analysis confirms the good crystalline nature of as prepared polyaniline hydrochloride/cerium oxide nanocomposite. 3.2. Micro structural Analysis a

b

Figure 3.2 (a&b) FE-SEM images of polyaniline hydrochloride/cerium oxide nanocomposite

Field emission scanning electron microscopic (FE-SEM) analysis represents the morphology of the polyaniline hydrochloride/cerium oxide nanocomposite at different magnifications. Figure 3.2 (a&b) shows the FE-SEM micrograph images of nanocomposite. The particles are spherical and aggregated morphology with average diameter of 80nm. The outer surface of the spherical composite covered with nanofiber. This is because of cleft on outer surface of the spherical cerium oxide particles which trait the formation of nanofiber on its surface. This spherical structure of nanocomposite was obtained by the addition of nanocrystalline cerium oxide particles in polyaniline matrix. 3.3. Compositional analysis - energy dispersive spectroscopy

3.3.EDAX spectra of polyaniline/cerium oxide

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The elemental analysis of polyaniline hydrochloride/cerium oxide composites were carried out by using FESEM/EDAX. Figure 3.3 depicts the presence of elements namely carbon, nitrogen, oxygen, sulphur, chlorine and cerium was found to be 68.0%, 13.06%, 7.52%, 1.52%, 8.5% and 1.06% respectively. It confirms the presence of cerium element, nitrogen and sulphur impurities in the prepared polyaniline hydrochloride/cerium oxide nanocomposite. 3.4. Thermal Analysis

Fig. 3.4.TGA of polyaniline hydrochloride/cerium oxide nanocomposite

The TG analysis was carried out from room temperature to 900°C under nitrogen gas atmosphere. The TGA curve of composite (Fig.3.4) shows three inflexions. The first decomposition observed at 100°C due to the water evaporation from the polyaniline hydrochloride/cerium oxide nanocomposite. The second weight loss obtained in the range 180-330°C was due to the decomposition of dopant from polymer matrix. The third weight loss observed between 350-900°C due to degradation of polymer back bone. The polyaniline hydrochloride/cerium oxide composite shows the good thermal stability and the formation of polyaniline hydrochloride/cerium oxide nanocomposite was also confirmed by 20% weight loss at 350˚C and 80% weight loss at 900˚C. It has been repeatedly reported that the thermal stability of polyaniline was up to 700˚C [1, 10&24]. In this work the addition of cerium oxide particles increase the thermal stability of the nanocomposite up to 900˚C. 3.5. Surface area Analysis The surface area and the porosity property of as prepared polyaniline hydrochloride/cerium oxide nanocomposite were analyzed. Fig.3.5 a) shows the type IV nitrogen adsorption and desorption isotherm with high p/p0 which indicate the presence of mesopores on the surface of as prepared nanocomposite [32,33] and surface area was 21.39m2 /g. Fig.3.5 b) shows the narrow pore size distribution (BJH), in the range 2 to 350 nm, and the pore radius is in the size 14.5 nm.

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Fig.3.5 (a &b) Pore size distribution of polyaniline hydrochloride/cerium oxide nanocomposite 3.6. Optical Analysis Fig.3.6.1. shows the UV-Vis spectroscopy of polyaniline hydrochloride/cerium oxide nanocomposite and the nanocomposite was in emeraldine state with absorbance peaks at 312 nm &338 nm and 605 nm due to electron transition between benzenoid rings (π-π*) and charge transfer from benzenoid ring to quinoid ring respectively [1, 24, 15]. The absorption band from 600-700 nm is considered due to the agglomeration of cerium oxide nanoparticles. The broad band at 480-800 nm can be presume as the integrate effect of cerium oxide nanoparticle and transition from highest occupied energy level to lowest unoccupied energy level of quinonoid ring [25].

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Fig.3.6.1. UV-Vis spectroscopy of polyaniline hydrochloride/cerium oxide nanocomposite

3.6.2. Photoluminescence Spectroscopy The photoluminescence (PL) spectrum of polyaniline hydrochloride/cerium oxide nanocomposite is shown in Fig.3.6.2. The sample is excited under 350 nm the emission wavelength was observed at 441nm corresponding to blue emission due to the artefact [26, 27, 28] and the recombination of electron and hole pairs.

Fig.3.6.2.PL Spectra of polyanilinehydrochloride/Cerium oxide Nanocomposite

3.7. FTIR- Spectra Analysis The important characteristic peaks were observed in FTIR spectra of polyaniline hydrochloride/cerium oxide is shown in Fig. 3.7. The peak at 3446 cm-1 is due to the N-H stretching vibration of aromatic amine and vibration bands of O-H [30]. The peaks at 2920 cm-1 is corresponding to the aromatic C-H stretching vibration [29]. The peaks at 787 cm-1 and 592 cm-1 are due to C-H out-of-plane bending vibration and Ce-O bonds [31]. The peaks at 1288cm-1 and 1529cm-1 is assigned to the C–N stretching [31] and C=C starching vibration of bezenoid ring . The peak at 1117 cm-1 is due to in-plane bending vibrations of C–H mode of N=Q=N, Q=N + H=B and B–N + H–B. formed during protination and this measure of electron delocalization in polyailine chain [14].

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Fig.3.7. FTIR Spectra of Polyaniline hydrochloride/Cerium oxide Nanocomposite

4. Conclusion Polyaniline hydrochloride/cerium oxide nanocomposite was prepared by in situ chemical polymerization method and the formation of spherical nanostructure was confirmed by FE-SEM images. Structural anlysis shows that the cerium oxide nanoparticle improves the crystalline nature of the polyanilne. TGA, UV-Vis and FTIR spectral analysis confirm the interaction between polyaniline matrix and cerium oxide nanoparticles. Photoluminesence studies of the nanocomposite showing strong blue emision suggest that the polyaniline hydrochloride/cerium oxide nanocomposite can be ued in electroluminesence and display devices. Aknowledgement Authors are grateful to PG and Research Department of Physics, Government arts college (Men) ,Nandanam, Chennai-35, India for providing the reasearch facilities. References [1] Manawwer Alam, Anees A.ansari, Naser M.Alandis, Arabian journal of Chemistry (2013),6, 341-345 [2] Asif Ali Khan, Umair Bai., Composites: Part B 50 (2014) 862-869. [3] Nazish Parveen, Neelima Mahato, Mohd Omish Ansari, Moo Hwan Cho, Composite Part B 87 (2016) 281-290. [4]J.S.M. da silva, S.M.de Souza, G.Trovati, E.A.Sanches, J. Molecular Structure 1127 (2017) 337-344. [5] Suyog M. Pethe, Subhash B. Kondawar, Adv.Mat.Lett. (2014), 5(12), 728-733. [6]Shaojun Guo, Shaojun Dong, Erkang Wang, Small, (2009), 5, No.16, 1869-1876. [7] Ruiwen Yan, Baokang Jin, Dan L.i, Jun Zheng, Yuying Li, Cheng Qain, synthetic Metals 235 (2018) 110-114. [8] Jen-Hsien Huang, Mohammed Aziz Ibrahem,Chih-Wel Chu, RSC Adv,(2013), 3,26438-26442. [9] Qianhui Wu, Guowang Diao, Chemical Engineering Journal 304 (2016) 29-38. [10] Dhaneswar das, Lakhya J.Borthakur, Swapan K.dolui, RSC Adv.,2016, 6, 44878-44887 [11] Haibo Yang, Ting Ye, Ying Lin, RSC.Adv., (2015),103488– 103493. [12] Xin Xi, Ruili Liu, Tao Huang, Yi Xu, Dongqing Wu, J. colloid & Interface Science 483 (2016) 34-40. [13] Panbo Liu, Ying Huang, Jing Yan, Yang Zhao, J.Mater. Chem.C 2016, 4, 6362. [14] Ferooze Ahmad Rafiqi, Kowsar Majid, Synthetic Metals 202 (2015) 147-156. [15] Kuestan A. Ibrahim, arabian Journal of Chemistry, (2017), S2668-S2674.

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[16] Xiazhang Li, Junchao Qian, Zhigang Chen, Powder Technology 239 (2013) 415–421 [17] Fanming Meng, Leini Wanga, Jingbiao Cui, c. Journal of Alloys and Compounds 556 (2013) 102–108 [18] S.R.Takpire, K.R.Nemade, S.A. Waghuley,Materilas and Design 101 (2016) 294-300. [19] Rahy, A.Yang D.J., Mater. Lett. 2008, 62, 4311–4314. [20] Fanming Meng , Leini Wang, Jingbiao Cui, Journal of Alloys and Compounds 556 (2013) 102–108. [21] Fujun Miao, Changlu shao, Xinghua Li, Electrochimica Acta 176 (2015) 293-300. [22] Pandiaraj Sekar, Sreekumar kurungot, Applied Materials & interfaces Vol.7, issue.14 (2015) 7661-7669. [23] L.Ai, Y.Liu, X.Y.Zhang, Z.Y.Ge, Synthetic Metals 191 (2014) 41-46 [24] Salma Bilal, Anwar-ul-Haq Ali Shah, Synthetic Metals 206 (2015) 131-144. [25] Anees A.Ansari, D.Malhothra, J.Nanosci. Nanotechnol. 2009, Vol. 9, No.3. [26] Debanghsu Chaudhuri , D. D. Sarma, Chem. Commun., 2006, 2681–2683 [27] Amrut. S. Lanje1, Advances in Applied Science Research, 2010, 1 (2): 36-40 [28] S. Raja, M. Deepa,Indian Journal of Advances in Chemical Science 3(2) (2015) 198-203 [29] P.Muhamed Ashraf, K.V.Lalitha, Leela Edwin, Sensors and Actuators B 208 (2015) 369-378. [30] Linghao He,Bingbing Cui, Zhihong zhang, Sensors and Actuators B: Chemicals, Volume 258, (2017) 813-821. [31] S.Mandal, S.S.Mahapatra, R.K.Patel, J.environmental chemical Engineering, 3 (2015) 870-885. [32] Laveena P.D’Souza, R.Balakrishna, Industrial &Engg.Chem.Research,Vol.52,issue 46,16162-16168 [33] Wanlu Yang, Zan Gao, Jun Wang, j.Power sources 272 (2014) 915-921.