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Manganese oxide (MnO2) is an alternative metal oxide material that has potential as an energy storage application. In this study, the cryptomelane-type MnO2 doped Fe3+ and Cu2+ were successfully prepared using the sol-gel method. Fumaric acid is added to the KMnO4 in aqueous solution and modified with FeCl3.6H2O and CuCl2.2H2O to form different properties. Phase transformation and lattice parameters of the products were characterized using X-ray diffractometry (XRD). SEM observed the morphology of the sample, and electrical properties were tested using RCL meter. The results showed that adding Fe3+ and Cu2+ provided a higher value of conductivity and capacity of MnO2.

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Reduced graphene oxide has been synthesized by microwave irradiation assisted. The effect of microwave irradiation on its crystal structure and electrical conductivity was investigated. Graphene oxide was synthesized using a modified hummers method then reduced by LAA (L-Ascorbic Acid) as a reducing agent with microwave irradiation assisted. The irradiation time varied by 10, 20, 30, and 40 minutes. The samples characterized by Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy-EDAX (SEMEDAX), X-Ray Diffractometer (XRD), and Inductance Capacitance and Resistance Meters (LCR-Meters).

Chicken feathers are agricultural wastes and become pollutants because of the resistance to protease degradation. Feathers contain a fibrous protein called keratin and potentially for producing activated carbon. In many applications, activated carbon is made of composites with poly (vinylidene fluoride) PVDF to improve its function. This research was carried out to study the effect of PVDF composition on activated carbon derived from chicken feathers on electrical properties. Besides evaluating changes in chemical structure and surface morphology, composites were tested using FTIR and digital microscopy. An addition of PVDF improves its dielectric properties. But the higher composition, causing agglomeration that inhibits polarization. The dielectric constant and conductivity of composite with 15 wt% PVDF are 1950 and 1.45 x 10−5 S/cm at 1 kHz, larger than another composition.

Bi4Ti3O12 dan SrTiO3 merupakan material semikonduktor yang berpeluang untuk digunakan sebagai fotokatalis. Namun, kedua material tersebut memiliki kekurangan karena hanya mampu bekerja pada daerah sinar UV dan memiliki laju rekombinasi yang cepat. Pembuatan material heterojunction merupakan salah satu upaya untuk mengatasi masalah ini. Riset ini bertujuan untuk mempelajari sifat fotokatalitik komposit Bi4Ti3O12/SrTiO3 yang disintesis dengan metode sonikasi. Hasil penelitian menunjukkan bahwa Bi4Ti3O12/SrTiO3 berhasil disintesis tanpa adanya pengotor. Mikrograf SEM menunjukkan bahwa Bi4Ti3O12 berbentuk plate-like sedangkan SrTiO3 berbentuk irregular spheres. Data UV-Vis DRS menunjukkan bahwa nilai energi celah pita Bi4Ti3O12/SrTiO3 dengan perbandingan mol (1/1), (1/2), (1/4), dan (1/6) berturut-turut adalah 3,178; 3,70; 3,137, dan 3,160 eV.

Bright upconversion luminescence and increased Tc in CaBi 2 Ta 2 O 9 :Er high temperature piezoelectric ceramics

<p class="AbstractText"><span lang="EN-AU">An increase in the consumption of chicken meat may have an impact on the waste of chicken feathers. Several efforts have been made to treat chicken feather waste, which is difficult to decompose and can pollute the environment. Chicken feathers are biomass with a high keratin content that has the potential to be used as a carbon material. In this study, chicken feathers were used in the chemical exfoliation method to produce reduced Graphene Oxide (rGO) material. Chicken feathers are heated in two stages, at temperatures of 250 and 400 </span><span lang="EN-AU">℃ in the air</span><span lang="EN-AU">. The exfoliation procedure was carried out with varying concentrations of HCl (0, 0.5, 1, 1.5, and 2 M). The X-ray diffraction spectra revealed that the sample had a rGO type carbon phase, with the crystal size decreasing as the HCl concentration increased. The presence of functional groups C-O, C=C, and C-OH identified as GO/rGO was revealed by FTIR spectra. The HCl exfoliation process reduced the sample's conductivity and capacitance, with the highest values obtained in aquadest sample (GO-0 M), about 10^-5 S/m and 10^-7 F/m².</span></p>