Articles

Found 8 Documents
Search

PEMBUATAN DAN KARAKTERISASI KARBON AKTIF DARI BAMBU BETUNG (DENDROCALAMUS ASPER) DENGAN AKTIVASI KOH BERBANTUAN GELOMBANG MIKRO Hutapea, Erin Mazelly; Iwantono, Iwantono; Farma, Rakhmawati; Saktioto, Saktioto; Awitdrus, Awitdrus
Komunikasi Fisika Indonesia Vol 14, No 2 (2017)
Publisher : Universitas Riau

Show Abstract | Original Source | Check in Google Scholar

Abstract

Activated carbon had successfully been made from betung bamboo (Dendrocalamus Asper) bycarbonization process for 1 hour with chemical activation using pottasium hydroxide (KOH) with themass ratio of the carbon powder with KOH i.e. 1:0, 1:1, 1:2 and 2:1. In order to activate the carbon,the activation was help by microwave irradiation with the power of 630 Watt for 20 minutes. Thepurpose of this research is to characterize activated carbon using X-ray diffraction (XRD), FourirerTransform Infrared Spectroscopy (FTIR) and absorption of methylene blue. The data of X-raydiffraction pattern indicated that all of the activated carbon were in a semi-crystalline form, with theXRD peaks observed at angel of diffraction (2θ) of 21.268o and 41.014o with oriented of (002) and(100) respectively. The highest value of layer (Lc) is resulted from the ratio 1:1 as high as 21.495 nmand this data supported by the highestabsorption of methylene blue at ratio 1:1 as high as 99.327mg/g. Characterization of FTIR showed that the activated carbon had the function of cluster –OH, CHand C=C. Overall the calculated and analyzed results showed that the variation of KOHconcentration influences the qualities of the activated carbon.
EFEK WAKTU RENDAM AKTIVASI KIMIA BERBANTUAN GELOMBANG MIKRO TERHADAP SIFAT FISIKA KARBON AKTIF DARI KULIT BUAH JENGKOL (PITHECELOBIUM JIRINGA) Asra, Yurike; Iwantono, Iwantono; Saktioto, Saktioto; Farma, Rakhmawati; Awitdrus, Awitdrus
Komunikasi Fisika Indonesia Vol 14, No 2 (2017)
Publisher : Universitas Riau

Show Abstract | Original Source | Check in Google Scholar

Abstract

Activated carbon based on jengkol fruit shell at soaking times assisted pottasium hydroxide (KOH)activation by microwave has successfully been made, the ratio of carbon mass to KOH of 2:1. Thechemical activation soaking time was varied at 24 hours, 36 hours, and 48 hours. The aims of thisresearch was to study the effect of soaking time on the physical properties of activated carbon ofjengkol shell that represented by micro structure, surface area, adsorption, and chain structure ofactivared carbon. The micro structure pattens of samples were in semi-crystralline structure as thepresence of quite narrow 2 peaks at 2θ : 22,994o and 42,102o representing the crystal orientation of(002) and (100). The highest of stack height (Lc) was produced from the sample with soaking times 24hours which was 1,773 nm, with surface area of 124,50 m2/g. The adsorption of methylen blue was ashigh as 99,569mg/g and chain stucture of activated carbon based on jengkol shell was obtainedfunction group of C-H, C-C, C=O, and C-O at wave number of 2943,43 cm-1, 2369,65 cm-1, 1612,56cm-1 and 1160,23 cm-,1 respectively.
KARAKTERISASI SIFAT OPTIK DAN MORFOLOGI NANOROD ZnO YANG DIDOPING GALIUM (ZnO;Ga) Novita, Sri; Iwantono, Iwantono; Awidrus, Awidrus
Komunikasi Fisika Indonesia Vol 14, No 1 (2017)
Publisher : Universitas Riau

Show Abstract | Original Source | Check in Google Scholar

Abstract

ZnO nanorods have been successfully grown on the surface of FTO (Fluorine Tin Oxide)byhydrothermal method at a temperature of 90 ° C for 8 hours. In this study,It will be analyzed theeffect of percentage variation of gallium at 0%, 0.5%, 1%, 1.5%, 2%, 2.5% and 3% to the opticaland morphological properties of the grown ZnO nanorods. The samples were analyzed usingUV-Vis spectroscopy and Field Emission Scanning Microscope (FESEM). The UV- Vis spectrashowed that the strong reflectance observed at the wavelength of 400-800 nm. The 2.5% Gadoped ZnO was the lowest reflectance compared to other samples. The FESEM images showedthat gallium doped ZnO nanorods grew ontothe surface FTO with hexagonal face shape. It wasalso observed that the 2.5% doped Ga sample was the most uniform and formed verticalorientation array.
PENGARUH PENAMBAHAN MATERIAL PLASMONIK PERAK (Ag) TERHADAP SIFAT FISIS NANOROD ZnODENGAN METODE SEED-MEDIATED HYDROTHERMAL Anggelina, Fera; Iwantono, Iwantono; Umar, Lazuardi; Awitdrus, Awitdrus
Komunikasi Fisika Indonesia Vol 14, No 2 (2017)
Publisher : Universitas Riau

Show Abstract | Original Source | Check in Google Scholar

Abstract

ZnOnanorods with addition of plasmonic materials of silver (Ag) have successfully been grown ontoFlourine Tin Oxide (FTO) substrates by using seed-mediated hydrothermal method though twosteps: seeding and growing processes. Ag was added to the ZnOnanorods after finishing theZnOnanorods growth process at a temperature of 90°C for 8 hours. Effect of Ag to the physicalproperties was evaluated by using the characterization techniques of X-Ray Diffraction (XRD),Field Emission Scanning Electron Microscopy (FESEM)-Energy Dispersive X-Ray (EDX), and UVVisspectroscopy. XRD pattern of the sample did not show special diffraction peak of Ag. FESEMphotograph confirmed that the Ag was substituted to the ZnOnanorods lattice. The presence of Ag inthe ZnOnanorodsaffected tobroken a part of the surface of ZnOnanorods, vary the diameter size ofthe ZnOnanorods and vertical orientation of ZnO array was not formed perfectly. In addition, thepresence of Ag in the ZnOnanorods was confirmed by EDX spectrum of sample that observed 0.2%of Ag-weight percentage. The addition of Ag to the ZnOnanorods positively affected to opticalproperties of ZnO, as absorption spectrum of sample become wider, ranked from UV to visible. Itwas concluded that addition of Ag to the ZnOnanorods active material of DSSC can increase theefficiency of the cell significantly.
EDDY CURRENT SENSOR BERBASIS FLAT COIL FR4 UNTUK MENENTUKAN KETEBALAN PELAT LOGAM NON MAGNETIK AL Emrinaldi, Tengku; Salomo, Salomo; Hamzah, Yanuar; Iwantono, Iwantono; Umar, Lazuardi
Spektra: Jurnal Fisika dan Aplikasinya Vol 2 No 3 (2017): SPEKTRA: Jurnal Fisika dan Aplikasinya, Volume 2 Nomor 3, Desember 2017
Publisher : Program Studi Fisika Universitas Negeri Jakarta

Show Abstract | Original Source | Check in Google Scholar | Full PDF (391.066 KB)

Abstract

Abstrak Sensor arus eddy (eddy current) digunakan untuk pengukuran ketebalan logam khususnya logam non magnetik seperti alumunium.  Penelitian ini telah mengembangkan sensor eddy current berbahan PCB (printed circuit board) jenis FR4 yang memiliki ketebalan lapisan tembaga 35micron. Prototipe yang dihasilkan mempergunakan koil sensor dengan jumlah gulungan (n) 30 lilitan, diameter (Æ) 30mm, lebar dan jarak antar koil, (dkoil) 0,254mm dan tahanan (Rkoil) sebesar 4,26Ω. Respon sensor ketebalan pelat logam terhadap bahan uji dievaluasi dengan memberikan eksitasi frekuensi tunggal 700Khz, 1MHz dan 1.33MHz. Rangkaian ketebalan pelat telah mempergunakan rangkaian pengunci fasa (phase locked loop) dan mampu mengukur variasi ketebalan  mulai 0,2 mm sampai 2 mm, sementara jarak antara sensor dengan logam uji dijaga konstan 2 mm. Hasil pengukuran memberikan respon kurva U(t) dalam hubungan Kata-kata kunci:sensor eddy current, PCB FR4, material non magnetik, ketebalan logam, rangkaian phase locked loop Abstract Eddy current sensor is used to measure the thickness of metals, especially non-magnetic metals such as aluminum. This research has developed eddy current sensor made from PCB (printed circuit board) type FR4 which has 35micron copper layer thickness. The developed prototype uses a designed coil sensor with the number of winding (n) 30 turn, diameter () 30mm, width and distance between coils, (dkoil) 0.254 mm and coil resistance (Rkoil) of 4.26 Ω. The sensor response to the test material was evaluated by giving a single frequency excitation of 700 Khz, 1 MHz and 1.33 MHz. The plate thickness electronics has used a phase locked loop circuit and is capable to measure the thickness variations from 0.2 mm up to 2 mm, while the distance between the sensor coil and the test object was kept constant at 2 mm. The measurement results give the U (t) curve response in the exponential relationship. Keywords: eddy current sensor, PCB FR4, nonmagnetic material, thickness, phase locked loop circuit
MORFOLOGI DAN EFISIENSI SEL SURYA FOTOELEKTROKIMIA BERBASIS NANOSTRUKTUR ZnO DILAPISI TEMBAGA Iwantono, Iwantono; Natalia, Sella; Abdi, Rinaldo; Awitdrus, Awitdrus; Zulkarnain, Zulkarnain
Komunikasi Fisika Indonesia Vol 15, No 2 (2018)
Publisher : Universitas Riau

Show Abstract | Original Source | Check in Google Scholar

Abstract

ZnO nanostructures coated Cu (Copper) have been successfully grown using a method of seed mediated hydrotermal. The growth of Cu coated ZnO nanostructures were used as an active material of DSSC. The Cu on ZnO nanostructures has been coated at a concentration of 10 mM at room temperature in 30 minutes. The samples were characterized using Field Emission Scanning Electron Microscope (FESEM), Energy Dispersive X-ray (EDX). The FESEM images showed that the geometrical shape of ZnO nanostructures was nanoflower. Spectra of EDX showed Cu was really exist in all samplesof about 0.8%. A DSSC was fabricated by using the ZnO nanostructured coated Cu as an active material.The results of I-V measurements under iluminattion of halogen lamp its intensity of 100 mW/cm2 has produced efficiency 0.35% (DSSC without copper) and increasedto 0,43% whenCuwas coated on ZnO.
EFEK PENAMBAHAN ATOM TEMBAGA (Cu) DAN PERAK (Ag) PADA MATERIAL AKTIF NANOMATERIAL ZnO SEL SURYA FOTOELEKTROKIMIA Windayani, Windayani; Iwantono, Iwantono; Awitdrus, Awitdrus; Zulkarnain, Zulkarnain
Komunikasi Fisika Indonesia Vol 16, No 1 (2019)
Publisher : Universitas Riau

Show Abstract | Original Source | Check in Google Scholar

Abstract

ZnO material coated with Cu + Ag was successfully grown using seed mediated hydrothermal method at a temperature of 90° C for 8 hours with a variation of concentration of Ag, 10 mM, and 20 mM. The growth of ZnO nanomaterials was carried out on the FTO substrate (Flourine Tin Oxide). The Samples were characterized using, Field Emission Scanning Microscope (FESEM), and X-ray Diffraction (XRD). The FESEM photos show ZnOnanorod  coated with Cu + Ag have grown on FTO having a nanoflower shape that consructed from ZnOnanorods with their orientation . The XRD pattern shows five peaks at 2θ: 31.69 °; 34.36 °; 36,18 °; 47.52 °; and 56.4 °. Based on the results of the analysis of the OriginPro 8 program each peak in a row according to the crystal orientation (100), (002), (101), (012), and (110). The stongest line was found in the crystal plane (101). DSSC was fabricated using ZnO nanomaterial coated with Cu + Ag as active material, N719 dye, liquid electrolyte, and plastisol as catalyst on the counter electrode. The results of I-V measurements at halogen lamp with ilumination its intensity of 100 mW/cm2 of the cells has producedthe highest efficiency value based on Cu coated ZnO was based DSSC 0,98% with a Cu concentration of20mM.These results show that the addition of Cu layer can increase the efficiency of DSSC based on ZnO by 123% compared to ZnO without Cu based DSSC. Addition of Ag to active material of Cu coated ZnO nanomaterial did not have a positive effect on the efficiency of DSSC cells.
ANALISA DIMENSI, DENSITAS DAN KAPASITANSI SPESIFIK ELEKTRODA KARBON SUPERKAPASITOR DARI BUNGA RUMPUT GAJAH DENGAN VARIASI KONSENTRASI PENGAKTIVAN KOH Taer, E.; Yusra, H.; Iwantono, Iwantono; Taslim, R.
Spektra: Jurnal Fisika dan Aplikasinya Vol 1 No 1 (2016): SPEKTRA: Jurnal Fisika dan Aplikasinya, Volume 1 Nomor 1, Agustus 2016
Publisher : Program Studi Fisika Universitas Negeri Jakarta

Show Abstract | Original Source | Check in Google Scholar | Full PDF (183.879 KB)

Abstract

Abstrak Telah dilakukan analisa dimensi, densitas dan kapasitansi spesifik pada pembuatan elektroda karbon superkapasitor dari bunga rumput gajah menggunakan variasi konsentrasi aktivator KOH. Pembuatan elektroda karbon diawali dengan proses prakarbonisasi, penggilingan dengan ball milling dan diayak dengan ukuran partikel < 53 µm. Proses berikutnya dilakukan aktivasi kimia menggunakan aktivator KOH dengan variasi konsentrasi sebesar 0,3 M, 0,5 M dan 0,7 M. Pelet karbon dibuat dengan alat hydraulic press pada tekanan 8 ton. Proses karbonisasi dilakukan pada suhu 600°C pada lingkungan gas N2 dengan profil pemanasan bertingkat, dan diikuti dengan proses aktivasi fisika menggunakan gas CO2 pada suhu 850°C . Hasil penelitian ini diperoleh bahwa diameter, ketebalan dan massa setiap elektroda superkapasitor mengalami penurunan seiring dengan peningkatan konsentrasi KOH. Sedangkan densitas dan kapasitansi spesifik mengalami peningkatan dengan pertambahan konsentrasi KOH. Nilai kapasitansi spesifik tertinggi diperoleh sebesar 100,62 F/g dengan densitas 0,87 gr/cm3 pada variasi 0,7 M KOH. Kata-kata kunci: Analisa Dimensi, Kapasitansi Spesifik, Superkapasitor, Bunga Rumput Gajah, Variasi KOH Abstract Dimensions, density and specific capacitance of carbon electrode supercapacitor from flower of elephant grass by using various KOH concentrations has been analyzed. Production of  carbon electrodes was performed by pre-carbonization, grinding by ball milling and sieving to a find a particle size of < 53 µm. The following process was an activation by chemical activation using KOH by various concentrations of 0.3 M, 0.5 M and 0.7 M. Carbon pellets were produced by hydraulic press instrument at a pressure of 8 tons. Carbonization process was carried out at a temperature of 600°C in a N2 gas environment with multilevel heating profile, and followed by physical activation process by throwing CO2 gas at a temperature of 850°C. The results of this study showed that the diameter, thickness and mass of each carbon electrode supercapacitor decrease with the increasing of  KOH concentrations. While the density and specific capacitance were increased with the increasing of KOH concentrations. The highest specific capacitance value was obtained as high as 100.62 F/g with a density of 0.87 g/cm3 in the variation of 0.7 M KOH. Keywords: Dimensional Analysis, Specific Capacitance, Supercapacitors, Flower Elephant Grass, Variations KOH