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PENUMBUHAN CARBON NANOTUBE DENGAN TEKNIK MILLING MENGGUNAKAN FE SEBAGAI KATALIS PENUMBUH Yunasfi, Yunasfi; Mustofa, Salim; Muflikhah, Muflikhah
Jurnal Sains Materi Indonesia Vol 14, No 1: OKTOBER 2012
Publisher : Center for Science & Technology of Advanced Materials - National Nuclear Energy Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (430.169 KB) | DOI: 10.17146/jsmi.2012.14.1.4637

Abstract

PENUMBUHAN CARBON NANOTUBE DENGAN TEKNIK MILLING MENGGUNAKAN Fe SEBAGAI KATALIS PENUMBUH. Telah dilakukan penumbuhan Carbon Nanotube (CNT) dengan teknik milling menggunakan partikel Fe sebagai katalis penumbuh. Campuran serbuk Fe-C berukuran nano dibuat dari campuran serbuk grafit dan Fe dalam berbagai variasi persen berat Fe (1% berat hingga 5 %berat), lalu diproses milling memakai teknik High Energy Milling (HEM) selama 50 jam. Hasil analisis pola difraksi sinar-X menunjukkan hadirnya puncak-puncak karbon C(002), C(004) dan C(110) dan puncak Fe(101) dan Fe(200), Puncak karbon menurun intensitasnya dan cenderung amorf dengan meningkatnya%berat Fe, sedangkan puncak Fe makin menajam. Hasil pengamatan struktur mikro dengan TEM memperlihatkan adanya penumbuhan awal CNT dengan dimensi yang dipengaruhi %Fe. Pada kandungan 2 % berat Fe terbentuk struktur CNT dengan ukuran lebih panjang dibanding pada kandungan berat Fe lainnya. Pembentukan CNT ini juga teridentifikasi dari spektrum Raman yang memperlihatkan hadirnya puncak G-band pada 1590 cm-1 dan puncak D-band pada 1310 cm-1 dengan intensitas ID yang lebih tinggi dibanding IG serta tak hadirnya puncak RBM-band pada bilangan gelombang rendah. Kondisi ini merupakan jenis spektrum untuk bahan dengan struktur Multi Wall Carbon Nanotube (MWCNT). Rasio ID/IG tertinggi pada 2 % berat Fe mendukung hasil analisis dimensi CNT dari pengamatan Transmission Electron Microscope (TEM). Secara umum dari data-data yang diperoleh pada penelitian ini dapat ditunjukkan bahwa Fe dapat berfungsi sebagai katalis dalam penumbuhan CNT.
GROWTH OF CARBON NANOTUBE BYAPPLYING ION IMPLANTATION TECHNIQUE Mustofa, Salim; Yunasfi, Yunasfi
Jurnal Sains Materi Indonesia Vol 13, No 2: FEBRUARI 2012
Publisher : Center for Science & Technology of Advanced Materials - National Nuclear Energy Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (444.575 KB) | DOI: 10.17146/jsmi.2012.13.2.4714

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GROWTH OF CARBON NANOTUBE BYAPPLYING ION IMPLANTATION TECHNIQUE. The use of ion implantation technique for growing carbon nanotubes (CNT) has been studied. Implantation technique with its high and focused energy is used for implanting Ni+ ion, which can act as catalyst for CNT growth. CNT was grown by implantation of Ar+ and Ni+ ion to the nanostructured carbon thin film that were deposited on Si(100) substrate. The dose of ion implantation parameter was varied between 5 x 1015 to 1 x 1017 ion/cm2. After implantation, the phase identification by X-Ray diffraction (XRD) and observations of surface and cross section morphology of samples by Scanning Electron Microscopy (SEM) in order to investigate the growth of CNT were carried out. The XRD analysis shows the peak of C(002), Ni(010) and Si(100) on the C/Si thin film samples after ion implantation, which indicate the carbon film still in a crystalline structure. The peak of Ni(010) is slightly decreased with the increasing of ion dose. The observation by SEM shows that the greater the dose of implants, the more unflat surface found on a thin film. While from the observation of cross section, it was indicated that the higher dose implants, more clearly the growth of CNTs on the surface of C/Si thin film. CNT is predicted to grow as a result of interaction between ion radiations with carbon, leading to the formation of CNTs.
ENHANCEMENT OF GIANT MAGNETORESISTANCE IN FE2O3-MWCNT/PVA NANOCOMPOSITE FILM Purwanto, S.; Adi, Wisnu Ari; Mustofa, Salim
Jurnal Sains Materi Indonesia Vol 16, No 3: APRIL 2015
Publisher : Center for Science & Technology of Advanced Materials - National Nuclear Energy Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (234.155 KB) | DOI: 10.17146/jsmi.2015.16.3.4225

Abstract

ENHANCEMENT OF GIANT MAGNETORESISTANCE IN Fe2O3-MWCNT/PVA NANoCOMPOSITE FILM. Synthesis and magnetic properties characterization of Fe2O3-MWCNT/PVA nano Composite film were carried out. Fe2O3-MWCNT as a filler of nano Composite thin film were synthesized using simple mixing methods froma solution containing FeCl3, and Multi-Walled Carbon Nanotube (MWNT). The solution was sonicated for almost 20 minutes then dried at 450 oC for one hour. The mixture of the two composition was dispersed with Sodium Dodecyl Sulfate (SDS) in 20 mL aquabidest and homogenized by ultrasonicator for 15 minutes at 40 oC. Then filler was then mixed with Polyvinyl Alcohol (PVA) with some various concentration and dried overnight at room temperature. X-Ray Diffraction (XRD) analysis and Raman Spectroscopy were used to find out the presence of Fe2O3 phase in as prepared sample. Iron oxide phase partially filled in the wall of MWCNT observed by Transmission Electron Microscope (TEM). The Giant Magnetoresistance (GMR) properties were investigated. The maximum GMR value was negative 80% of the composition 1:9 filler/matrix volume ratio. The linear negative of the magnetoresistance (MR) ratio is coincident with a model as proposed by Nguyen, Spivak and Shklovskii (NSS) and related to the effect of quantum interference between Fe2O3-MWCNT in PVA matrix.
PREPARATION OFNB BASED THIN FILM USING PULSED LASER DEPOSITIONAND ITS ELECTRICAL PROPERTY Mustofa, Salim; Yusuf, Saeful
Jurnal Sains Materi Indonesia Vol 14, No 4: JULI 2013
Publisher : Center for Science & Technology of Advanced Materials - National Nuclear Energy Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (167.377 KB) | DOI: 10.17146/jsmi.2013.14.4.4388

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PREPARATION OFNb BASED THIN FILM USING PULSED LASER DEPOSITIONAND ITS ELECTRICAL PROPERTY. The research for largering capacity of dielectric multi layer type capacitor using Pulsed Laser Deposition (PLD) method was carried out. In this study, we focus on the inexpensive material Nb as a substitute for expensive material Ta, which is currently used for ferroelectric material. The Nb-based (Nb2O5) and TiO2 particle were deposited on Si/SiO2 substrate at temperature of 600 oC under the oxygen pressure of 5Pa, and Pt was used as the last layer. Doping of TiO2 to the Nb2O5was carried out by alternately replacing each target and finally the deposited film with a thickness of 200 nm was achieved. The capacity value of pure Nb2O5 thin film was higher than pure TiO2 , but TiO2 was more stable against the changes of temperature. The capacitor that has a ratio of 30% Nb2O5 showed the highest capacity value. Single layer of Nb2O5 thin film has the largest rate of change in capacitance, and the capacitor that already doped by TiO2 has a more less changes in capacitance against the changes of temperature. In order to crystallize, the capacitor was then annealed in the air for 12 hours at the temperature of 700o . Same as before annealing, a mixed thin film thas has a ratio 30% of Nb2O5 still showed the highest capacity value, even there is a small changes against the against the changes of temperature. Other mixed thin film with different ratio of TiO2 have more stable temperature characteristics, but the capacity value was very small. From above results, it can be considered that the thin film of 30% of Nb2O5 and 70% of TiO2 is the best potential with highest capacity value and small changes against the changes of temperature.
Analisis Penambahan Fe Terhadap Sifat Listrik Dan Magnet Komposit Mwcnt-Fe Purwanto, P.; Mustofa, Salim
Jurnal Kimia dan Kemasan Vol. 36 No. 2 Oktober 2014
Publisher : Balai Besar Kimia dan Kemasan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (948.923 KB)

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Bahan komposit MWCNT-Fe dibuat dengan mencampurkan serbuk MWCNT dan Fe dengan variasi kandungan Fe mulai dari 1% sampai 5%. Selanjutnya bahan komposit diproses milling selama 3 jam memakai teknik High Energy Milling (HEM). Hasil pola difraksi sinar- x komposit MWCNT-Fe menunjukkan adanya puncak MWCNT dan Fe dengan pola yang sama. Spektroskopi Raman menunjukkan puncak D band muncul pada 1310- 1320 cm-1, puncak harmonik kedua G band (G’ band) muncul pada Raman shift 1605 cm-1 sampai dengan 1615 cm-1, dan puncak tangensial G band muncul pada 1580 cm-1 sampai dengan 1595 cm-1. Hasil pengukuran konduktivitas MWCNT-Fe dengan alat ukur LCR, menunjukkan bahwa nilai konduktivitas mengalami kenaikan sebanding dengan kenaikan berat Fe. Hasil parameter magnetik dengan metode VSM (Vibrating Sample Magnetometer) menunjukkan Magnetik Rimanen (Mr), Magnetik Jenuh (Ms) mengalami kenaikan, sedangkan Medan Koersif (Hc) mengalami penurunan sebanding dengan kenaikan berat Fe. 
SYNTHESIS AND CHARACTERIZATION OF GRAPHITE NANOSTRUCTURE THIN FILM WITH SPUTTERING TECHNIQUE Yunasfi, Yunasfi; Mustofa, Salim; Deswita, Deswita
Jurnal Sains Materi Indonesia VOL 13, NO 1: OKTOBER 2011
Publisher : Center for Science & Technology of Advanced Materials - National Nuclear Energy Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (287.158 KB) | DOI: 10.17146/jusami.2011.13.1.5401

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SYNTHESIS AND CHARACTERIZATION OF GRAPHITE NANOSTRUCTURE THIN FILM WITH SPUTTERING TECHNIQUE. Synthesis and characterization of graphite nanostructure thin film using the DC-sputtering technique has been carried out. Nanostructured graphite for target of deposition using DC-Sputtering technique has been prepared by milling technique using High Energy Milling (HEM) with the variation of milling time between 50 hours until 100 hours. First, the graphite target was prepared by doing a compaction using press machine to the nanostructured graphite powder got from milling process. Secondly, a thin filmof graphite was fabricated using DC-Sputtering technique. The phase identification of nanostructured graphite thin filmwere carried out using X-Ray Diffraction (XRD), and the surface and cross section morphology of thin filmwere observed using Scanning Electron Microscopy (SEM). XRD identification shows the presence of peaks of Si(100) and C(002) in all conditions of preparing powder using for target, but a shift of the angel?s peak to the left and the decreasing of peak intensity were found. While the observation using SEM to surface morphology of thin film shows that the form of thin films are mostly homogeneous, smooth and flat at the milling time of 50-75 hours. From the SEM photograph of cross section, it is shown that there is a tendency of the more commonly found particles of droplets on the surface of thin film with the increasing of milling process against the carbon powder as a constituent of pellets for the DC-Sputtering targets, especially in the case of C/Si thin filmfabricated using target prepared by milling for 100 hours, the morphology of surface was worst.
Short Time Synthesis of Titania Nanotubes: Effect of Pre-Mixing Prior Hydrothermal Kartini, Indriana; Jannah, Ira Nur Arba’atul; Amalia, Fitri Rizki; Mustofa, Salim; Kunarti, Eko Sri; Swasono, Respati Tri
Indonesian Journal of Chemistry Vol 19, No 1 (2019)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (19.78 KB) | DOI: 10.22146/ijc.26777

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The effect of pre-mixing by mechanical stirring before hydrothermal and hydrothermal time on the crystalline phases and morphology of titania has been studied. It was shown that nanotubes titania can be obtained after 5 h hydrothermal at 150 °C. The XRD patterns and Raman spectra of the produced powders showed the existence of anatase and titanate crystalline phases. At the longest stirring, TiO2 (B) was observed. High textural coefficient for [200] plane of anatase (TC200) confirmed oriented growth of one-dimensional anatase along [200]. All powders resulted at various stirring time were nanotubes, as confirmed by Transmission Electron Microscope (TEM). It was found that the longer the stirring, the higher the surface area of the nanotubes. All powders showed type-IV isotherm for nitrogen gas adsorption/desorption, indicating the existence of mesoporous materials. However, long hydrothermal induced the nanospheres formation, hence reducing the surface area. The band-gap of the resulted titania nanotubes were ranging from 3.11–3.16 eV. The photocatalytic performance toward the degradation of methylene blue of the titania nanotubes was higher (~50%) compared to the bulk TiO2 (~5%) under visible-light and was comparable under UV-light (~60%). These results pave a way of producing visible-sensitive TiO2 photocatalyst by altering the morphology.
RESEARCH AND DEVELOPMENT OF NANO-STRUCTURED CAPACITOR MATERIAL BY USING ?-IRRADIATION Yunasfi, -; Mustofa, Salim
Teknologi Indonesia Vol 37, No 2 (2014)
Publisher : LIPI Press

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14203/jti.v37i2.218

Abstract

Research and development on the usage of g-irradiation against nano-structured graphite which is suitable for capacitor material has been carried out. The nano-structured graphite in the form of pellet was irradiated by g-ray with variation of dose, from 100 kGy up to 600 kGy. In this research, the analysis of phase changes, the change of electrical resistivity (r), dielectric constant (er) and dielectric loss (tan d), have been carried out to the nano-structured graphite after irradiated by g-ray. The results of XRD showed that g-radiation could decline the peak intensity. The peak intensity decreased with the addition of radiation dose. Electrical resistivity values (r) also fell as an impact of g-radiation, where the decline continues with increasing radiation dose, while the value of the dielectric constant (er) has increased by g-radiation and increased steadily with the increasing of radiation dose. For the case of tan d t?? he tendency was decreased by the g-radiation and this decline continued with the increasing radiation dose. This fact suggests that there has been an interaction between g-radiation with graphite particles which can cause the impactof changes in the structure of graphite. More impact of changes in the structure of graphite is assumed that greater of energy can be stored, thus diminishes the r value and tan d, while the value of er increases.
Synthesis and Characterization of Reduced Graphene Oxide from Fiber of Borassus Flabelifer by Activation Method Prasetya, Fandi Angga; Anggarini, Ufafa; Mustofa, Salim; Sholihah, Syarifatus; Iqbal, Fathur; Hanafi, Hanafi; Septyano, Dode Bara
Jurnal Fisika FLUX Vol 16, No 1 (2019): Jurnal Fisika Flux Edisi Februari 2019
Publisher : Lambung Mangkurat University Press

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/flux.v16i1.5876

Abstract

Reduced Graphene Oxide (RGO) has been successfully synthesized by calcination process at 4000C for 4 hours followed by activation with NaOH 1 M. Carbonization is the last process with variations in heating at 6500C, 7500C, 8500C, and 9500C for 1 hour (heating rate 100C / minute). DSC-TGA data shows that there is advanced decomposition at high temperatures, this is confirmed by SEM data which shows the amount of porosity which is getting higher with a size that decreases with temperature. XRD data shows phase differences at low temperatures with a trend of higher levels of crystallinity at high temperatures. Raman spectroscopy data showed an ID / IG ratio of 2.607 and 1.007 on Borassus Flabelifer L with carbonization at 6500C and 9500C respectively. The ID / IG value which is getting closer to 1 indicates that the carbon available in Borassus Flabelifer L has undergone phase changes such as Graphene with a little Oxide commonly called RGO
PERUBAHAN SIFAT MAGNETIK BAHAN KOMPOSIT FE-C OLEH RADIASI SINAR GAMMA Yunasfi,, Yunasfi,; Mustofa, Salim; Purwanto, Setyo; Mashadi, Mashadi; Madesa, Tria
Jurnal Sains Materi Indonesia EDISI KHUSUS: OKTOBER 2007
Publisher : Center for Science & Technology of Advanced Materials - National Nuclear Energy Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (474.298 KB) | DOI: 10.17146/jusami.2007.0.0.5137

Abstract

PERUBAHAN SIFAT MAGNETIK BAHAN KOMPOSIT Fe-C OLEH RADIASI SINAR GAMMA. Telah dilakukan penelitian terhadap perubahan sifat magnetik bahan komposit Fe-C oleh radiasi sinar gamma. Fe-C dibuat dari campuran serbuk Fe dan serbuk karbon, dengan rasio komposisi berat kandungan Fe dan karbon 50 % dan 50 %. Dalam penelitian ini, diamati perubahan sifat magnetik bahan komposit Fe-C setelah diiradiasi dengan sinar gamma pada dosis 250 kGy. Identifikasi struktur bahan komposit Fe-C yang telah diiradiasi dilakukan dengan metode XRD (X-Ray Diffractometer ) dan karakterisasi sifat magnetik dilakukan dengan menggunakan VSM (Vibrating Sample Magnetometer). Hasil identifikasi dengan metode XRD menunjukkan adanya penurunan intensitas difraksi setelah iradiasi sinar gamma. Hasil pengukuran kurva histeresis M-H dengan VSM, menunjukkan bahwa bahan komposit Fe-C setelah diiradiasi memiliki Hc (medan koersiv), Ms (magnetisasi saturasi) serta Mr (magnetisasi remanen) lebih rendah dibanding dengan kondisi sebelum diiradiasi dengan sinar gamma pada dosis 250 kGy. Penurunan ini terjadi karena adanya cacat struktur di dalam bahan komposit Fe-C akibat interaksi radiasi sinar gamma dengan bahan komposit Fe-C.