We present solution-processed organic solar cells based on subphthalocyanine acceptors with strong light harvesting in the visible region and an efficiency up to 3.5%.

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Telah dilakukan penelitian tentang derajat deasetilasi kitosan dari cangkang rajungan. Penelitian ini bertujuan menentukan pengaruh konsentrasi NaOH dan lama perendaman terhadap derajat deasetilasi kitosan. Penelitian dimulai dengan mengisolasi kitin melalui tahap deproteinasi, demineralisasi, dan depigmentasi menggunakan NaOH 1M, HCl 1M dan H2O2 3% secara berurutan. Selanjutnya kitin yang diperoleh dianalisis dengan FTIR. Produksi kitosan dilakukan dengan cara deasetilasi kitin dengan melakukan dua variasi yaitu waktu perendaman selama 2, 4, 6, dan 8 jam dan variasi konsentrasi NaOH dengan konsentrasi 40, 50, 60, dan 70%. Selanjutnya kitosan yang diperoleh dianalisis dengan metode FTIR. Hasil penelitian menunjukkan bahwa derajat deasetilasi terbesar pada kondisi perendaman selama 8 jam dengan DD sebesar 77,99% dan konsentrasi NaOH 70% dengan DD sebesar 77%. Kenaikan derajat deasetilasi dipengaruhi oleh kenaikan waktu perendaman dan konsentrasi NaOH.

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Synthesis of ferrate (FeO4 2−) from iron plate of transformer waste electrochemically in high alkaline medium and its application for dye degradation has been carried out. The effect of parameters such as time, NaOH concentration, type of electrolyte solution and ferrate stability were studied. The ferrate solution formed is dark purple in colour with a maximum wavelength of 505 nm. The ferrate was compacted by fresh drying to produce Na2FeO4 crystals and characterized by XRF, XRD and FT-IR techniques. The ferrate was applied to degrade methylene blue, methyl orange, rhodamine and remazol black B dyes. The results showed the highest degradation of dyestuff in methylene blue by 98% and COD reduction by 73.69% at pH 8, ferrate dose of 1.1 mg and contact time of 70 min. This shows that ferrate is an environmentally friendly material which can be used to degrade toxic dyes.

Synthesis of ferrate using NaOCl and Fe(OH)3 from electrolysis of used iron, and its application for metanil yellow degradation had been done. The electrolysis was conducted using used iron and zink plates at anode and cathode electrodes, respectively, Na2SO4 electrolyte. The dissolved iron ion from the electrolysis then was made alkaline using NaOH pellet and NaOCl was soaked to the solution to form ferrate (FeO4 2-). The ferrate was used for metanil yellow degradation and it was compared with other oxidators such as permananate, hydrogen peroxide and dichromate. The ferrate solution formed was indicated by a change from brown to dark purple which was indicated the oxidation of Fe(III) to Fe(VI) with a maximum wavelength of 510 nm. The optimum degradation of metanil yellow by ferrate was obtained at pH 8, molar ratio of 2:1, and for 25 min. Ferrate was the most effective oxidator compared with permananate, hydrogen peroxide and dichromate.

Synthesis of eugenol-divinylbenzene copolymers were carried out by reacting eugenol with various percent weight of divinylbenzene in a reactor at room temperature for 24 hours in the presence of sulfuric acid as a catalyst. Methanol was used to quench the copolymerization process. The effect of DVB mass on copolymer properties was studied based on molecular weight, thermal stability, surface morphology and swelling degree of the copolymers produced. The weight percent of the added DVB was responsible for the molecular weight of the copolymer by multiplying the site for propagation in the copolymerization process. In addition, the greater DVB used the better thermal resistance of polymer is obtained, which is possibly due to the higher number of DVB causing the larger cross-linked polymer network to increase the polymer bond thermal resistance. The swelling degree value was also affected by the number of crosslinkers used, in which make the polymer material become harder to expand. However, the influence of the weight percent of DVB was not seen on the copolymer morphology.

High concentrations of creatinine and urea in the blood can be removed by dialysis using semipermeable membranes that are selective for certain species and hold other species through diffusion processes. This ability requires a membrane that has an active side, which functions as a targeted species identifier. The membrane must be biocompatible because the membrane will be in direct contact with the body’s biological systems. The membrane material that is made must be acceptable to the blood system so that there is no rejection from the body and have a large contact area to obtain an effective diffusion process. For this reason, a hollow fiber membrane (HFM) is needed. One of the synthetic polymers used as the base material for HFM is PSf. PSf has mechanical strength, heat resistance, and is easily formed into HFM. However, PSf has disadvantages such as lack of active side and less compatible with blood due to its hydrophobic properties. Modification using PEG and chitosan will reduce the hydrophobicity of the PSf. Membrane results were analyzed the physical, chemical, and transportability for urea and creatinine. The results of functional group characterization by FTIR show that the modification reaction was successfully carried out on polysulfone to produce PEG-PSf/CS. The modification succeeded in making the PSf membrane more hydrophilic, as evidenced by a decrease in the contact angle from 69.4° (PSf) to 53° (PEG-PSf/CS). Water uptake capability increases to 609%, and membrane porosity increases porosity increased from 72 to 83%. The water flux is also increased. Creatinine clearance ability increases from 0.09 mg/dl to 0.25 mg/dL. Urea clearance ability increases from 2.3 mg/dL to 3.07 mg/dL. The SEM image showed that the modification makes the membranes more porous.