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This study reported the modification of corncob cellulose using propylene carbonate and hexadecyltrimethylammonium bromide (CTAB) to impart the desired functionalities. The modified corncob cellulose was characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and zeta potential. Different parameters were studied in modifying functionalities of corncob cellulose, i.e., the ratio of CTAB and propylene carbonate, retention time and temperature. After modification, an increase in weight percent was obtained. According to the FTIR spectrum, there was an extra peak at 1780 cm-1 which belongs to C=O groups and an increase in intensity at 1000–1300 cm-1 which belongs to CN stretching of the quaternary ammonium group. SEM images and zeta potential results supported the quaternary ammonium group was successfully grafted on isolated corn cob cellulose, which are essential for initiating photocatalytic reactions.

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]