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1100092612 ICSIS iiiiliilill 1100091!612 'I he d I eel ot ;unmumum 111trate and ethylene glycol 10 carhoxyrnclh)l cellulose solid polymer clcctrol)tcs for rc:charl!c hh: prolnn butter) I Khad Jah llllmun J...mnarudm Perpustakaan Sultanah Nur Zahlra1t Univers1n M ala y~1a Terengganu. t.b~~; ~ ~ ~ "'v - PERPUSTAKAAN SULTANAH NUR ZAHIRAH UNIVERSITI MALAYSIA TERENGGANU (UMT) 21030 KUALA TERENGGANU I[OUU~oolZ f- ~-- f-.-- ' lihat Sebelah

THE EFFECT OF AMMONIUM NITRATE AND ETHYLENE GLYCOL IN CARBOXYMETHYL CELLULOSE SOLID POLYMER ELECTROLYTES FOR RECHARGEABLE PROTON BATTERY KIIADIJAII IIILMUN KAMARUDIN Thesis submitted in fulfillment of the requirement for the degree of Doctor of Philosophy in Physics in the School of Fundamental Science Universiti Malaysia Terengganu February 2016

ABSTRACT Abstract of thesis presented to the Senate of Universiti Malaysia Terengganu in fulfilment of the requirement for the degree of Doctor of Philosophy THE EFFECT OF AMMONIUM NITRATE AND ETHYLENE GLYCOL IN CARBOXYMETHYL CELLULOSE SOLID POLYMER ELECTROLYTES FOR RECHARGEABLE PROTON BATTERY KHADIJAH HILMUN KAMARUDIN February 2016 Main Supervisor School : Associate Professor Mohd llunar Nizam Mohamad Isa, Ph.D. : School of Fundamental Science Solid polymer electrolytes (SPEs) have been recognised as promising electrolytes to overcome the limitation in gevliquid counterparts. In this research, the potential of carboxymethyl cellulose (CMC)-based SPEs was studied. Two systems, namely System I which comprised of CMC doped ammonium nitrate (NH4N03) salt and System II which comprised of CMC-~03 plasticized ethylene glycol (EG) are prepared via solution casting technique. The interactions between polymer, salt and plasticizer in both systems are observed by FTIR analysis. The amorphousness and thermal behaviour of both systems are obtained by XRD and TGA-DTG analyses, respectively. The incorporation of 45 wt.% NH4N03 salt in System I has optimized the ambient temperature ionic conductivity to (7. 71 ± 0.04) x 10" 3 Scm '. Ionic conductivity is enhanced to (3.80 ± 0.06) x 10" 2 Scm ' on the addition of20 wt.% EG plasticizer in System 11. The temperature-dependent ionic conductivity for both electrolyte systems is Arrhenian and thermally activated. The activation energy did ll

not show the significant effect to the enhancement of ionic conductivity in both systems. However, the activation energy in System I is higher than in System II. Ionic conductivity is observed to be influenced by the number density (n), mobility (JI) and diffusion coefficient (D) of mobile charge carriers in System l. Whereas, ionic conductivity in System II is affected only by n and inversely proportional to J1 and D. These transport parameters are affected by the fraction of ionic species in both systems. The majority of mobile charge carriers is recognized to be ions as evidenced by transference number measurement via DC polarization technique. This analysis also supported that the mobile charge carriers in both systems are W cations or protons. Conduction mechanism in both systems is described by the relation of Jonschcr's universal power law and hopping mechanism models. Quantum mechanical tunneli ng model was identified to represent the ionic conduction mechanism in both systems. Electrical studies show that the SPEs are ionic conductors. The electrical behaviour of SPEs is attributed to the conductivity relaxation process. The highest conducting SPEs in both systems were applied in the fabrication of rechargeable proton batteries. Based on the batteries performance, it can be concluded that the rechargeable proton batteries in the present work are suitable to be applied in low current based electrochemical device applications. 111

ABSTRAK Abstrak tesis yang dikemukakan kepada Senat Universiti Malaysia Terengganu scbagai memenuhi kepcrluan untuk ijazah Doktor Falsafah KESAN AM ONIUM NITRA T DAN ETILENA GLIKOL DALAM ELEKTROLIT PEPEJAL POLIMER KARBOKSILMETIL SELULOSA UNTUK BA TERI PROTON CAS SEMULA KHADIJAH HILMUN KAMARUDIN Februari2016 Penyelia Utama Pusat Pengajian : Profesor Madya Mobd Ikmar Nizam Mobamad Isa, Ph.D. : Pusat Pengajian Saios Asas Elektrolit pepejal polimer (SPEs) telab dikenalpasti sebagai elektrolit yang berupaya untuk rnengatasi kekurangan yang dialami oleh elektrolit gel/cecair. Dalam kajian ini, potensi karboksilmetil selulosa (CMC) berasaskan SPEs telah dikaji. Dua sistem iaitu Sistem I terdiri daripada CMC berdop garam ammonium nitrat CN'H4N03) dan Sistem II terdiri daripada CMC-NJ-LtN0 3 berpemplastik etilena glikol (EG) telah disediakan melalui teknik penuangan larutan. Interaksi-interaksi diantara polimer, garam dan pemplastik dalam kedua-dua sistem telah dicerap melalui analisis IR. Keamorfusan dan perlakuan haba kedua-dua sistem diperolehi daripada analisis XRD dan TGA-DTG. Dengan penambahan 45 wt.% garam NH.tN03 dalam Sistem I telah mcngoptimumkan kekonduksian ion suhu ambien/sekeliling pada (7.71 ± 0.04) x 10" 1 Scm 1 Kckonduksian ion dipertingkatkan kcpada (3.80 ± 0.06) x 10" 2 Scm 1 dengan penarnbahan 20 wt.% pemplastik EG dalam Sistem II. Analisis kcbergantungan kekonduksian ion terhadap suhu menunjukkan kedua-dua sistem lv

t ~IJ,ILI:nnf'\.Ctt211 ~Uild1ld!l I'C\JII ~".dlllldfl Umversm r,1alays a Tcrenqganu. elektrolit adalah Arrhenian dan diaktifkan secara terrna. Tenaga pengaktifan tidak menunjukkan kcsan yang kctara terhadap penambahan kekonduksian ion dalam kedua-dua sistcm. Walau bagaimanapun. tenaga pengaktifan bagi Sistem I didapati lcbih tinggi berbanding Sistem II. Kekonduksian ion dipengaruhi oleh kepadatan nombor (n). mobiliti (p) dan pekali peresapan (D) pembawa cas bergerak dalam Sistcm I. Manakala, kekonduksian ion dalam Sistem II hanya dipengaruhi oleh n dan bcrkadar songsang dengan J.L dan D. Parameter-parameter angkutan ini dipengaruhi olch pecahan spesies-spesies ion. Majoriti pembawa cas bergerak dikenalpasti scbagai ion seperti yang telah dibuktikan oleh pengukuran jumlah pemindahan mclalui teknik pcngkutuban DC. Analisis ini juga menyokong bahawa pembawa cas bcrgcrak dalam kedua-dua sistem adajah H.. kation atau proton. Mekanisma kckonduksian untuk kedua-dua sistem diterangkan berdasarkan hukum kuasa sejagat Jonschcr dan model-model mckanisme lompatan. Model penerowongan mekanik kuantum telah dikenalpasti untuk mewakili mekanisma kekonduksian ion dalam kcdua-dua sistem. Kajian elektrik menunjukkan bahawa SPEs adalah pcngalirlkonduktor ion. Perlakuan elektrik SPEs adalah disebabkan oleh proses kekonduksian relaksasilkekenduran. SPEs dengan kekonduksian tertinggi dalam kcdua-dua sistem telah digunakan dalam fabrikasi bateri proton cas semula. Berdasarkan prcstasi daripada bateri-bateri tersebut, ia boleh disimpulkan bahawa bateri proton cas semula dalam kajian ini sesuai untuk diaplikasikan dalam pcnggunaan peranti elektrokimia berarus rendah. v