Mohd Sani Sarjadi

Synthesis of ion imprinted polymers for selective recognition and separation of rare earth metals

Lanthanide-ion imprinted polymers (L-IIPs) were synthesized by stoichiometric amounts of rare earth ions and the cavities in the polymers were created for the corresponding lanthanide ions. The maximum sorption capacities were estimated to be 125.3, 126.5, 127.6, 128.2 and 129.1 mg/g for Pr, Nd, Sm, Eu and Gd, respectively at pH 6. In the selectivity study, the L-IIPs exhibited good selectivity to the specific rare earth ions in the presence of coexisting cations. The imprinting results were found to be excellent with some rare earth ions over other competitor rare earth ions with the same charges and close ionic radius.

The recent development of carbazole-, benzothiadiazole-, and isoindigo-based copolymers for solar cells application: A review

This review summarized the photovoltaic performance and polymeric properties of the modified poly[N-9′-heptadecanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole)] in the 21st century. These modifications comprised fluorination, substitution, ladderization, spacer alteration, donoracceptor rearrangement, and etcetera. Besides that, this paper also sorted out the copolymers which are tailored from carbazole donor and isoindigo acceptor. Meanwhile, the copolymers that consist of both benzothiadiazole and isoindigo but not carbazole were also put together in this paper for better comparison purpose. The summary of all these modifications will be able to provide a better insight for the future molecular designation of the copolymeric backbones in the application of polymeric solar cells.

Synthesis of Carbazole Based Co-polymers Containing Thienothiophene and Benzothiadiazole Units in a Direct Arylation Scheme

The photovoltaic effect can be used to harvest energy from sunlight, enabling a cleaner approach to generating energy. Organic photovoltaics based on polymers are an attractive replacement of expensive, high energy consuming silicon solar cells. However, the limitations of efficiency have prevented industrial application, and polymer-based solar cells remain uncompetitive. Thus, optimisation of efficiency is required before potential application of these devices. In this work, the polymers were synthesised by direct arylation, in order to investigate its suitability for application in photovoltaic cell. Morphological, spectroscopic and charge-transport measurements are used to investigate the influence of either the dithienyl or thienothiophene moieties on the structure and photophysical properties of the copolymer rationalise the solar cell characteristics. The polymers obtained were characterised using 1H-NMR, 13C-NMR, IR, UV and thermal gravimetric analysis. The absorption spectral, thermal, electrochemical and photovoltaic properties of the random copolymers were investigated. Finally, a new series of carbazole-based dithienyl or thienothiophene polymers was successfully synthesised and characterised.

Synthesis of Tapioca Cellulose-based Poly(amidoxime) Ligand for Removal of Heavy Metal Ions

ABSTRACT Poly(acrylonitrile)/cellulose block copolymer (PAN-b-cell) was prepared by using a free radical initiating process and then the nitrile functional groups of the PAN blocks of the copolymers were transformed into amidoxime ligands. The resulting poly(amidoxime) ligands could complex with heavy metal ions; for example, the reflectance spectra of the [Cu -ligand]n+ was found to be at the highest absorbance, about 94%, at pH 6. The pH was the key parameter for metal ions sensing by the ligand. The adsorption capacity for copper was very good, 272 mg g−1, with a fast adsorption rate (t1/2 = 10 min). The adsorption capacities for other heavy metal ions such as Fe3+, Cr3+, Co3+ and Ni2+ were also good, being 242, 219, 201 and 195 mg g−1, respectively, at pH 6. The heavy metal ions removal efficiency from water was 98% at low concentration. The data proved that the heavy metal ions adsorption onto the polymer ligands were well fitted with the Langmuir isotherm model (R2>0.99), which suggests that the cellulose-based adsorbent surface namely the poly(amidoxime) ligand, was homogenous and a monolayer. The reusability was examined by a sorption/desorption process for six cycles and the extraction efficiency was determined. This new adsorbent could be reused for 6 cycles without any significant loss in its original removal function.

The Effect of the Seawater Treatment on the Thermal and Morphological Properties of Oil Palm Empty Fruit Bunches Filled Poly (vinyl alcohol)

Since Malaysia and the surrounding of the South East Asian countries has developed a large amount of oil palm EFB as a waste product after being processed as a fuel or other application, thus oil palm EFB fibre has displayed great potential as reinforcing material in polymer.The aim of this study to characterize the morphological and thermal effects of the seawater treated of oil palm empty fruit bunch single fibres and composites. The fibres of oil palm EFB has been treated using seawater from Pulau Tiga, at day-3 until day-30, the different filler loading of 1%, 3% and 5% of untreated and treated composites were prepared using casting method. The thermal properties of the composites of untreated and seawater treated were analysed using Thermogravimetric Analysis (TGA). Based on the thermal effect, Pulau Tiga composites have the good thermal stability due to the highest onset temperature. The morphological examined using Scanning Electron Microscopy (SEM). The morphological changes enhanced with the seawater treatment, however, at the filler loading of 5%, the composites easily cracked with more voids detected. In conclusion, seawater treatment significantly improved an extra enhancement in thermal stability and the morphological changes improved with the seawater treatment at 1% of the fibre loading.

Liquid Crystals Decorated Gold Nanoparticles for Photoswitching Properties

Md. Lutfor Rahman, Mohd Sani Sarjadi, Shaheen M. Sarkar, Mashitah M. Yusoff, Yuvaraj A. R., and Sandeep Kumar Faculty for Science and Natural Resources, Universiti Malaysia Sabah, 88400 Kota Kinabalu, Sabah, Malaysia, Faculty of Industrial Sciences & Technology, Universiti Malaysia Pahang, 26300 Gambang, Kuantan, Pahang, Malaysia, Raman Research Institute, Raman Avenue, Sadashivanagar, Bangalore 560080, India Email: lutfor73@gmail.com

Alternative pathway to brominate 2,13-benzothiadiazole: Preparation of 4,7-dibromobenzo[c]-1,2,5-thiadiazole via N-bromosuccinimide

This present work reports an alternative pathway to brominate the 2,1,3-benzothiadiazole (BT). The conventional method to brominate a phenyl/benzene ring is to use the bromine solution (Br 2 ) together with hydrobromic acid (HBr). This is because the phenyl/benzene rings exhibit high stability due to the delocalized -conjugation, which the substitution of bromines into the rings can only be done through a strong bromination source, e.g. the Br 2 /HBr. Besides that, there is another bromine source, known as N-bromosuccinimide (NBS), which is normally used for bromination of thiophene rings but not the phenyl/benzene ring. The bromination ability of NBS is relatively mild than the Br 2 /HBr. Herein, this research shows that bromination of benzene/phenyl ring through NBS is possible under a drastic condition that involved the usage of 96% concentrated sulphuric acid and chloroform at room temperature. This alternative pathway can be used when there is limit access to the Br 2 and bromination through NBS is relatively less dangerous than the Br 2 /HBr.