Abstract
The primary purpose of this study was to explore the role of innivativeness in explaining user satisfaction in using e-campus. The study uses only one independent variable which is ...innovativeness. Data were collected by mean of paper-and-pencil self-administered questionnaire. Data were collected from 500 undergraduate and postgraduate students from private university in Kuantan Malaysia using a validated set of questionnaire. A series of regression statistics has been performed to answer the research question. A regression model revealed that innovativeness had significant impacts on satisfaction with e-campus use with a total variance of 13. per cent. The study highlights the importance of innovativeness in in explaining e-campus satisfaction.
In this work, natural dyes based on anthocyanin and chlorophyll pigments were extracted from the powder of P. rubra flowers and S. androgynous leaves respectively and used as sensitizers to fabricate ...zinc oxide (ZnO) based dye-sensitized solar cell (DSSC). It was observed in optical properties analysis that anthocyanin molecules formed a better bond with ZnO surface compared to chlorophyll. Moreover, anthocyanin sensitized ZnO also exhibits higher increment in nanoparticles diameter compared to that of chlorophyll sensitized ZnO due to the chemical adsorption occurant. The anthocyanin sensitized DSSC also shows better photovoltaic performance with power conversion efficiency (PCE) of 0.038 % compared to chlorophyll sensitized DSSC which exhibited PCE value of 0.014 % due to better charges transfer at the interface between the dye molecule and ZnO nanoparticle.
The development of biopolymer electrolytes based on methylcellulose (MC) has been accomplished by incorporating ammonium bromide (NB) to the polymer-salt system. The biopolymer electrolytes were ...prepared via solution-casting method. The conductivity and permittivity characteristics of the material were studied. The biopolymer-salt complex formation have been analysed through Fourier Transform Infrared (FTIR) spectroscopy and X-ray diffraction (XRD). The conductivity of the sample was measured by EIS HIOKI. Upon addition of 20 wt.% of NB, highest conductivity of 3.25×10-4 μScm-1 was achieved at ambient temperature. The temperature dependence of the biopolymer electrolytes exhibit Arrhenius behaviour. This result had been further proven in FTIR study.
Cyclic voltammetry can be used to investigate the chemical reactivity of species ion via oxidation and reduction process. The purpose of this study is to determine the level energy of high occupied ...molecule orbital (HOMO) and low unoccupied molecule orbital (LUMO) in polythiophene (PT), Poly (3-thiophene acetic acid) (P3TAA), polypyrrole (PPY) and chlorophyll (Chlo) through oxidation and reduction of molecular ions by cyclic voltammetry method. PT, P3TAA, PPY and Chlo solutions were prepared in a solvent of acetonitrile at the concentration range of 10-2 to 10-4 M. The current-voltage measurements for these solutions are performed using cyclic voltammetry method on input voltage from -2.0 V to 2.0 V. The working electrode used is indium tin oxide (ITO). The result of voltammogram is showed that the activity of PT species were produced three oxidation and one reduction processes. The formal reduction potential, Eo¢ is 0.83 (positive) meaning that oxidation process was dominant. So that the reaction of PT species was exhibited irreversible electrochemical behavior. The reaction of P3TAA species was exhibited reversible electrochemical behavior, where the range value of oxidation, DEpa and reduction, DEpc were in range of 0.825 V to 1.120 V and -0.230 V to 0.131 V respectively. PYY species reaction was exhibited irreversible electrochemical behavior where two oxidation states occur within -0.145 V to -0.202 V and 0.870 V to 1.63 V respectively. The species activity of Chlo was exhibited irreversible electrochemical behavior where only the oxidation process was obviously appeared at range of 0.80 V to 0.95 V. The LUMO energy levels of PT, P3TAA PPY and Chlo were 5.84 eV, 5.34 eV, 1.10 eV and 3.85 eV respectively, while HOMO energy levels of PT, P3TAA PPY and Chlo were 4.61 eV, 4.25eV, 3.70 eV and 5.93 eV. The average value of energy gap of PT, P3TAA, PPY and Chlo were 1.23 eV, 1.08 eV, 2.23 eV and 1.10 eV respectively.
Dye-sensitized solar cell (DSSC) is a photovoltaic device that can be produced from natural source pigments or natural dyes. The selection of natural dyes for DSSC application is currently under ...research. The utilization of natural dye materials that are easy to obtain, cost-effective, and non-toxic can reduce waste during DSSC fabrication. Natural dyes can be extracted from plants through extraction and chromatography methods. The suitability and viability of utilizing natural dyes as photosensitizers in DSSCs can be predicted using appropriate software simulation by varying related parameters to produce high power conversion efficiency. In this context, the purpose of the review is to highlight the evolution of performance improvement in the development of DSSCs with consideration of natural dye extraction and software simulation. This review also focuses on the results of extracting natural dyes from herbal ingredients, which are still very limited in information, and several parts of herbal plants that can be used as natural dye sources in the future of solid-state DSSCs have been identified. Based on the results of this review, the highest efficiency was obtained for the DSSC that used chlorophyll pigments as natural dyes using
Peltophorum pterocarpum
leaves with 6.07%, followed by anthocyanin pigments as natural dyes using raspberries (black) fruits with 1.5%, flavonoid pigments as natural dyes using
Curcuma longa
herbs with 0.64%, and flavonoid pigments as natural dyes using
Indigofera tinctoria
flowers with 0.46%.
Graphical Abstract
Natural dye is attractive to be used in dye sensitized solar cell (DSSC) as an alternative sensitizer. The main advantage of natural dye is its low cost production. Only simple procedure is needed to ...produce natural dyes where the pigments of plant parts like flowers, leaves, fruits and tubers were extracted using common solvents in the laboratory. In addition, the resources of natural dye are not only abundant, but also completely biodegradable. In this work, the natural dye was produced by extracting anthocyanin pigment from Ardisia elliptica fruits and called as Ardisia elliptica dye (AED). The highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) level of AED was −6.06 eV and −3.88 eV respectively. AED is absorbed light in the green region with maximum absorption at a wavelength of 536.49 nm and the band gap was 2.31 eV which is acceptable as sensitizer for DSSC. Our photoelectrode of DSSC was fabricated by sensitizing zinc oxide (ZnO) nanoparticles layer with AED in different sensitizing duration (dye-loading time) and the best obtained photo conversion efficiency (PCE) was 0.04% which has been sensitized for 20 min.
Situasi pengurangan kadar kelahiran dan peningkatan tahap kesihatan penduduk merupakan antara faktor utama yang menjadikan Malaysia bakal menuju ke arah sebuah negara menua menjelang tahun 2035. ...Walau bagaimanapun, pelbagai isu berkaitan pengabaian dan penderaan warga emas kerap dihebahkan di media massa dan media cetak. Bagi mengatasi cabaran ini, kajian ini dijalankan untuk membina Model Perlindungan Hak-Hak Warga Emas dari Pengabaian Menurut Perundangan Islam di Malaysia (Model ERIsP). Pendekatan kajian reka bentuk dan pembangunan diterapkan dalam kajian ini. Berdasarkan pendekatan yang digunakan, kajian ini dikelaskan kepada tiga 3 fasa utama. Fasa pertama kajian ini merupakan analisis keperluan dengan melaksanakan pendekatan kajian literatur bersistematik dan sesi temu bual bersama warga emas yang dipilih. Keperluan pembinaan model ini dianalisis dengan menggunakan teknik analisis kandungan terhadap data kajian literatur dan teknik tematik terhadap data dan transkrip temu bual. Fasa seterusnya menggunakan Kaedah Fuzzy Delphi(FDM) bagi membina komponen dan elemen model menurut persepsi dan keputusan pakar. Fasa ketiga iaitu fasa terakhir kajian ialah penilaian kebolehgunaan model berasaskan temu bual bersama pakar. Penilaian ini dianalisis menggunakan Teknik Kumpulan Nominal (NGT). Hasil kajian yang diperoleh membuktikan bahawa Model ERIsP amat penting kepada golongan ini. Lima 5 komponen utama dan elemen-elemen komponen utama juga dipersetujui oleh kesemua pakar dalam kajian ini bagi memberikan perlindungan yang baik kepada warga emas. Pembangunan Model ERIsP juga dilihat amat signifikan untuk dijadikan sebagai panduan dalam memelihara hak-hak warga emas bagi mengatasi isu pengabaian golongan ini.
Hybrid solar cell (HSC) in a form of novel photovoltaic is considered among promising research topic due to its low cost's preparation and environmental friendly solar cells. This paper concerns a ...systematic study on concentration of TiO2 and effect of coating techniques towards solar cells's efficiency. However, this paper is limited to doctor blade and spin coating techniques only. These samples were then characterised based on morphology, thickness, optical absorption, electrical conductivity and solar cell's efficiency using various techniques including FESEM, profilometer, UV-Vis and, autolab with irradiance of 100 mW/m2. From the results, TiO2/PEDOT:PSS with dye Eugenia clavifora (EC) obtained the highest efficiency of 1.33% using doctor blade technique compared to 0.00108% for spin coating technique. Sample thickness was obtained at 60.25 ± 1.20 nm corresponding to the concentration of TiO2 at 0.20 M. Thus, it can be conclude that, power conversion efficiency (PCE) was dependent to the deposition techniques of the thin film.
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