Potensi 49% poli(metil metakrilat) cangkukan getah asli (MG49) sebagai elektrolit pepejal polimer untuk diaplikasi dalam sistem peranti elektrokimia telah dikaji. Filem MG49 dengan garam LiBF4 sebagai dopan disediakan dengan menggunakan teknik pengacuan larutan. Kekonduksian ion yang diuji dengan menggunakan alat spektroskopi impedans elektrokimia menunjukkan kekonduksian optimum pada penambahan 25% bt garam LiBF4, dengan nilai kekonduksian ion, 1.49×10-9 S.cm-1 pada suhu bilik. Pemerhatian struktur dan morfologi dijalankan dengan menggunakan analisis pembelauan sinar-X dan mikroskopi imbasan elektron. Hasil menunjukkan pengkompleksan dan penghabluran berlaku dalam sistem polimer elektrolit. Hal ini menyebabkan nilai kekonduksian elektrik yang rendah didapati walaupun telah mencapai tahap optimum penambahan garam LiBF4.
This paper reports on the effect of molecular weight on the morphological and mechanical properties of liquid epoxidised natural rubber acrylate (LENRA)/silica hybrid composites prepared by sol-gel technique. The sol-gel reaction was conducted at different concentration of tetraethylorthosilicate (TEOS), used as a precursor of silica. TEOS were introduced in 10, 20, 30, 40 and 50 parts per hundred rubber (phr) in the composites. Two different molecular weights of ENR were used to study the effect of molecular weight on the mechanical and morphological properties of the compounds. These compounds were cured by ultraviolet (UV) irradiation. The mechanical properties were studied through pendulum hardness and scratch tests. Higher molecular weight of ENR showed better mechanical properties than lower molecular weight. Transmission electron microscope was used to determine the silica size and to study the distribution and dispersion of the silica particles. High molecular weight showed greater distribution and dispersion of silica particles with diameter of 13 nm–256 nm. Morphological and mechanical properties of LENRA/silica hybrid composites were improved by using high molecular weight of ENR.
Ionic conductivity of composite polymer electrolyte PVC-Al2O3-LiClO4 as a function of Al2O3 concentration has been studied. The electrolyte samples were prepared by solution casting technique. Their ionic conductivity was measured using impedance spectroscopy technique. It was observed that the conductivity of the electrolyte varies with Al2O3 concentration. The highest room temperature conductivity of the electrolyte of 3.43 × 10-10 S.cm-1 was obtain at 25% by weight of Al2O3 and that without Al2O3 filler was found to be 2.43 × 10-11 S.cm-1. The glass transition temperature decreases with the increase of Al2O3 percentage due to the increasing amorphous state, meanwhile the degradation temperature increases with the increase of Al2O3 percentage. Both of these thermal properties influence the enhancement of the conductivity value. The morphology of the samples shows the even distribution of the Al2O3 filler in the samples. However, the filler starts to agglomerate in the sample when high percentage of Al2O3 is being used. In conclusion, the addition of Al2O3 filler improves the ionic conductivity of PVC-Al2O3-LiCIO4 solid polymer electrolyte.
Kajian terhadap elektrolit polimer berasaskan 49% poli(metil metakrilat) cangkukan getah asli (MG49) dengan
natrium iodida (NaI) dalam aplikasi sel suria terpeka pewarna (DSSC) telah dijalankan. Kesan kepekatan garam
ke atas sifat elektrokimia, morfologi, kimia dan kehabluran MG49-NaI telah dianalisis menggunakan spektroskopi
impedan elektrokimia (EIS), mikroskopi imbasan elektron (SEM), spektroskopi inframerah transformasi Fourier (FTIR)
dan pembelauan sinar-X (XRD). Morfologi keratan rentas menunjukkan struktur membran berliang mikro dan homogen.
Nilai kekonduksian ion tertinggi pada suhu bilik bagi membran elektrolit polimer MG49-NaI pada penambahan 30 %
bt. garam NaI adalah 8.86 × 10-5 S cm-1. Analisis inframerah menunjukkan interaksi antara atom oksigen dengan ion
natrium berlaku pada kumpulan berfungsi eter (C–O–C) dan karbonil (C=O). Sifat kehabluran MG49-NaI polimer
elektrolit didapati berkurang dengan peningkatan kepekatan garam. Analisis kronoamperometri memberikan nilai
nombor pindahan ion (tion) sebanyak 0.92 membuktikan elektrolit polimer MG49-NaI (30 % bt.) adalah pengkonduksi
jenis ion. Ujian prestasi DSSC keadaan pepejal bagi FTO/TiO2
-N719/MG49-NaI (30 % bt.)/I2
/Pt sampel telah memberikan
keputusan kecekapan setinggi 0.26% dengan prestasi fotovoltaik, Jsc, Voc dan ff masing-masing adalah 1.30 mA cm-2, 0.56
V dan 34.91. Membran dalam keadaan pepejal-kuasi atau separa pepejal memberikan nilai kecekapan 3.48 % dengan
nilai Voc = 0.75 V, Jsc = 12.71 mA cm-2 dan FF = 37.70.