A study on the synthesis of multiwalled carbon nanotubes (MWCNT) and zinc oxide (ZnO) hybrid materials using the mecahnochemical technique has been conducted. MWCNT was dispersed in sodium dodecyl sulfate (SDS) solution. ZnO was formed at milling time between 2 and 5 hours, where at 10 hours the XRD results showed only small peaks of ZnO. This suggests that at longer milling time, the ZnO crystals were either become amorphous or have reduced in sized so as not to be detected using XRD. ZnO has also been doped with Manganese (Mn) which have affected the crystal structure and surface morphology of the sample.Keywords:Doping, Manganese nitrate, Mechanochemical technique, Multiwalled carbon nanotubes (MWCNT), Surfactant method , Zinc Oxide (ZnO)

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The structural, electronic and optical properties of pure and neodymium (Nd) doped anatase titanium dioxide (TiO2)are investigated via first-principles calculations within density functional theory (DFT) approach. The band gap reduces to ~0.398 eV when Ti4+ is substituted with Nd3+ in TiO2 crystal structure. The presence of Nd 4f states in the conduction band of TiO2 clarifies the reducing of the band gap. The dielectric constant and refractive index of Nd-doped TiO2 increase compare to pure TiO2. Nd-doped TiO2 able to enhance light absorption to longer wavelength spectrum. The first-principles results obtained satisfy the criteria for Nd-doped TiO2 to become feasible photoanode material in dye-sensitized solar cell (DSSC) device.

First-principles study based on density functional theory (DFT) framework for structural, electronic and optical properties of titanium dioxide (TiO2) in anatase and rutile phases are investigated. Anatase phase exhibits wide band gap compare to rutile phase. The partial and total density of states for TiO2 (anatase and rutile) describes the occupying of titanium (Ti) and oxygen (O) atoms at each energy level. TiO2 has a high dielectric constant to avoid the recombination process while its high refractive index provides the efficient of light diffusion. The optical absorption of TiO2 occurs in ultraviolet (UV) light of the wavelength photon. The results from the first-principles calculations will be helpful to give an understanding about the properties of TiO2 as promising photoanode in dye-sensitized solar cell (DSSC).

The declination of science interest appears to be a significant concern as becoming a global trend issue. As the government will face negative impact from this issue, the government encourage any contribution effort from the universities and industries to increase the social interest. Thus this study was conducted for the purpose of investigating the influencing aspects in students' stream choice of either physics or biology stream. 36 respondents chosen are students from third semester for 2017/2018 session of Diploma in Science from Universiti Teknologi MARA (UiTM) Perak Branch Tapah Campus. Data collection was done quantitatively from questionnaires participated by all respondents through an academic program named 'Running Physicists' which organized by the faculty. Demographic and contributing factors from family background, peer, and passion were measured as the prompting aspects in student's stream choices. Cronbach's Alpha for demographic factor is 0.815 of consistency value gives reliable value for measuring respondents' opinion. The contribution factors show significant relation on family, peer, and passion with mean value of 3.59, 2.95 and 4.32 respectively for physics respondents and mean value of 3.71, 2.71 and 4.43 correspondingly for biology respondents. The enrolment of respondents in stream choice is dominated by personal abilities and passion with the subject's background.