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Mixed iron molybdenum multisulfide composite thin films had been deposited at 550 °C for 20 min from dual source precursors of Cp2Fe and [CpMo(SMe)2]2 (2) via AACVD method. The 10, 20, 40, and 80 mol% of added Cp2Fe as the dopant produced thin films with different morphologies, particle sizes, thicknesses, and oxidation states for the iron atom. The x-ray diffraction (XRD) analyses showed the presence of MoS2/Mo2S3/Fe(MoS2)2 while the existence of standing flakes array was observed in the 3D atomic force microscopy (AFM) analyses. The photoelectrochemical study of these thin films revealed that at overpotential of 1.23 V vs RHE under solar simulator of 100 mW/cm2, the 40 mol% Fe-doped thin film comprising both Fe2+/Fe3+ yielded the highest photocurrent density of 1.241 mA/cm2, while the 80 mol% Fe-doped thin film containing only Fe3+ showed lower photocurrent density of 0.761 mA/cm2 but with the highest photosensitivity of 1.396 with the longest lifetime for the electron hole recombination. However, the electrochemical impedance spectroscopy (EIS) analyses showed that the 80 mol% Fe-doped thin film with the thickest coating had the lowest charge mobility. This study had shown that the amount of doped iron in molybdenum multisulfide and its oxidation state also influenced its photoelectrochemical properties as well. The mechanism of electron transfer involved in this study has been illustrated by a Z-scheme. [ABSTRACT FROM AUTHOR]

Composites consisting of a polymeric matrix and renewable resources have attracted scientific attention due to the idea of sustainable development. The objective of this study was to blend the polyvinyl alcohol (PVOH) and oil palm ashes (OPA) using solution casting approach. The results revealed that increasing the OPA loading in PVOH film would decrease both tensile strength and elongation at break of the blended films. The morphology of the tensile fractured surface was examined which supported the result obtained from tensile properties. Also, the thermal characteristics of PVOH/OPA films were studied. The glass transition temperature and crystallization temperature were increased when the OPA loading was increased. Thermogravimetric analysis indicated that the thermal stability of PVOH/OPA film was higher than the unfilled PVOH film. [ABSTRACT FROM AUTHOR]

In the present study, characterization and morphological study of oil palm ash (OPA) and thermal properties of OPA-filled natural rubber (NR) compounds were carried out. The morphological study revealed that the OPA particle was irregular with rough surface and porous structure. Energy dispersive x-ray analysis and an x-ray fluorescence spectrometry indicated that silicon was the highest component in OPA. Fourier transform infrared analysis and x-ray diffraction indicated that the main mineralogical components in OPA were quartz and calcite. The study results of the OPA-filled NR compounds showed that the thermal resistance and retention properties after thermal ageing were notably enhanced with the addition of OPA and improved as the OPA loading was increased. [ABSTRACT FROM PUBLISHER]

Chemically modified Oil Palm Ash (OPA)-filled natural rubber composites were prepared by modifying the functional group of OPA with cetyltrimethylammonium bromide (CTAB) prior to compounding by using laboratory conventional laboratory-sized two-roll mills. The functional groups of CTAB-modified OPA were analyzed by using Fourier Transform Infrared (FTIR) and compared with those of non-modified ones. The CTAB-modified OPA-filled NR composites showed shorter scorch time and cure time as compared to those of non-modified OPA, which was attributed to the new functional groups occurred. The tensile test results showed that the OPA-filled NR composites with CTAB modification exhibit improvement in tensile strength, tensile modulus, and hardness but lower elongation at break as compared to nonmodified ones. The tensile fractured surface of modified OPA filled NR composites revealed the well embedded and better distribution of CTAB-modified OPA in NR matrix. The toluene uptake was also found to be lower for the modified OPA-filled NR composites and showed better rubber-filler interaction; it further showed that surface modification with CTAB could compatibilize the OPA particles and NR matrix. POLYM. COMPOS., 35:691-697, 2014. © 2013 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]