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All Journal Jurnal Penelitian Fisika dan Aplikasinya (JPFA) Omega: Jurnal Fisika dan Pendidikan Fisika Jurnal Pendidikan Fisika dan Keilmuan (JPFK) Indonesian Review of Physics (IRiP) Makara Journal of Science
wipsar sunu brams dwandaru
Yogyakarta State University,
Astronomy Earth & Planetary Sciences Education Materials Science & Nanotechnology Physics

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OPTICAL PROPERTIES COMPARISON OF CARBON NANODOTS SYNTHESIZED FROM KANGKUNG (IPOMOEA AQUATICA) WITH DEEP FRYING AND ROASTING TECHNIQUES Dwandaru, Wipsar Sunu Brams; Suhendar, Haris; Santoso, Iman; Sari, Emi Kurnia; Sari, Dyah Silviana; Fauzi, Fika
Jurnal Penelitian Fisika dan Aplikasinya (JPFA) Vol 9, No 2 (2019)
Publisher : Universitas Negeri Surabaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26740/jpfa.v9n2.p123-131

Abstract

Carbon nanodots (Cdots) have many unique properties such as luminescence that can be utilized in various fields. The purposes of this study are to synthesize Cdots from kangkung (Ipomoea aquatica) through frying and roasting techniques and compare the optical properties of the Cdots using UV-Vis, PL, and FTIR. Three stages of synthesizing process of Cdots, i.e.: preparing the kangkung powder (root, stem, leaf) and synthesizing the Cdots through frying and roasting techniques. Each part (root, stem, and leaf) was heated in an oven at 250 oC for 2 hours and mashed into powder. The frying method was done by frying 15 g of the powder in 120 ml oil for 5 minutes at 88 oC, filtered, and dissolved in n-hexane. In addition, the roasting method was done by frying the powder without oil as much as 15 g for 5 minutes, dissolved in 120 ml of distilled water, and then filtered. The UV-Vis characterization showed one absorbance peak for Cdots via frying and roasting techniques at 293 nm to 296 nm and 262 nm to 282 nm, respectively. The Cdots through frying and roasting techniques produce red and green luminescence, respectively. The FTIR characterization showed the presence of C=C and C=O functional groups, which are the core and surface state of the Cdots by frying technique, while the samples via roasting technique showed only the core. It can be concluded that the Cdots samples obtained from frying and roasting methods have different optical properties. The frying method produces Cdots with longer wavelength at the absorbance peak in the UV-Vis test compared to the roasting method. Moreover, the frying and roasting methods produce different color luminescence.
Preparation and Synthesis of Micro-Sized Carbon Material from Coconut Shell with Variation of Material Mixing Time Using a Blender for Fe Filtration of Mataram Canal Water Dwandaru, Wipsar Sunu Brams; Pratama, Buki Wahyu; Andriani, Nur Baeity; Hastuti, Irnawati Widya
Omega: Jurnal Fisika dan Pendidikan Fisika Vol 3 No 2 (2017)
Publisher : Program Studi Pendidikan Fisika UHAMKA

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31758/OmegaJPhysPhysEduc.v3i2.50

Abstract

This study aims to synthesis micro-sized carbon material from coconut shell leftovers or wastes using piezoelectric-based ultrasonication in liquid phase. The micro-sized carbon material produced is then utilized as a filtration material for Mataram canal water in Yogyakarta. This study begins with synthesizing the micro-sized carbon material by mixing i) mashed coconut shells, ii) 100 ml distilled water, and iii) 2 grams of detergent into a blender. The aforementioned materials are blended with mixing time variation of 30 minutes and 60 minutes. The resulted solution is left alone for a night and then ultrasonicated for 4 hours. The solution is then characterized using UV-Vis spectrophotometer. The sediments obtained from the carbon materials are characterized using X-ray diffraction (XRD) for each mixing time variation whereas scanning electron microscopy (SEM) is conducted upon the micro-sized carbon material with 60 minutes mixing time. The solution and the sediment is poured onto a filter paper, heated until dry, and fitted to a simple filtration device. Water from Mataram canal is used to test the Fe filtration ability of the micro-sized carbon material. The water samples before and after filtration are characterized using atomic absorption spectroscopy (AAS). The UV-Vis results show that increasing the mixing time of material, increases the absorbance value. Based on XRD results the synthesized micro-sized carbon material from coconut shell has an amorphous phase. The SEM result at 60 minutes of mixing time looks like an irregular bulk material with sizes of about 1 $\mu$m to 12 $\mu$m with thicknesses of around 0.6 $\mu$m to 0.8 $\mu$m. The AAS results indicate that the longer the mixing time, the lower the Fe content in the water samples after filtration.
Integrasi Project Based Learning dalam Science Technology Engineering and Mathematics untuk Meningkatkan Keterampilan Proses Sains dalam Pembelajaran Fisika Jatmika, Surya; Lestari, Sri; Rahmatullah, Rahmatullah; Pujianto, Pujianto; Dwandaru, Wipsar Sunu Brams
Jurnal Pendidikan Fisika dan Keilmuan (JPFK) Vol 6, No 2 (2020)
Publisher : UNIVERISTAS PGRI MADIUN

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25273/jpfk.v6i2.8688

Abstract

Penelitian ini bertujuan untuk mengetahui pengaruh project based learning (PjBL) berbasis science technology engineering and mathematics (STEM) terhadap kemampuan keterampilan proses sains peserta didik dalam pembelajaran Fisika. Penelitian ini menggunakan rancangan pre-experiment dengan jenis one-group pretest-postest design. Penelitian ini menggunakan satu kelompok (kelas) dengan teknik pengambilan sample random (acak). Kelas yang digunakan, yaitu kelas X MIPA 4 di SMA N 1 Yogyakata.  Responden penelitian sebanyak 36 peserta didik. Hasil analisis menunjukkan bahwa terjadi peningkatan hasil tes awal dan tes akhir. Semua indikator keterampilan proses sains yang diukur juga mengalami peningkatan. Peningkatan yang terjadi termasuk dalam kategori sedang. Hasil analisis uji-t one group pretest and posttest menunjukkan bahwa model PjBL terintegrasi STEM mempengaruhi keterampilan proses sains peserta didik. Berdasarkan hasil angket tanggapan peserta didik terhadap penerapan PjBL berbasis STEM secara keseluruhan sebesar 78,21%. Hasil ini menunjukkan bahwa penggunaan model PjBL terintegrasi STEM dalam pembelajaran fisika memberikan pengaruh positif terhadap keterampilan proses sains peserta didik.
Carbon Dots Synthesized from Tofu Pulp for Liquid Tofu Waste Photo-degradation Nurohman, Yosi; Pratidhina, Elisabeth; Sari, Emi Kurnia; Dwandaru, Wipsar Sunu Brams
Indonesian Review of Physics (IRiP) Vol 4, No 1 (2021)
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/irip.v4i1.3327

Abstract

This study was aimed to prepare and characterize carbon dots (CDs) from tofu pulp for liquid tofu wastes photo-degradation. The tofu pulp was dried, heated in an oven for an hour at 250 oC, mashed into powder, weighted as much as (g) 1; 2; 3; 4; and 5, dissolved into 100 ml distilled water, filtered, and characterized using UV-Vis, PL, and FTIR. The photo-degradation experiment was conducted for pure waste, waste + CDs, and waste + CDs + UV light, then the BODs were measured. The CDs reduced the wastes to 14.29% and 53.90% without and with UV light, respectively. The pure wastes, wastes + CDs, and wastes + CDs + UV light produced BOD values of (mg/l) 385; 200; and 135, respectively. The decrease in BOD showed that CDs with and without UV light successfully restore dissolved oxygen in the wastes.
Morphological and Structural Studiesof ZnO Micro-Nanorod Structures Synthesized Using a Low-Cost Hydrothermal Method Alfarisa, Suhufa; Toruan, Parmin Lumban; Atina, Atina; Dwandaru, Wipsar Sunu Brams; Safitri, Rika Noor
Makara Journal of Science
Publisher : UI Scholars Hub

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Abstract

Micro-nanorod structuresof zincoxide (ZnO) have been successfully synthesized via a simple and low-cost hydrothermal method. ZnO solutions with different concentrations of 0.05 and 0.1 M were prepared using zinc nitrate tetrahydrate and hexamethylenetetramine precursors. They were dissolved inaquadesand stirred before the hydrothermal process at 95 °C for 4 hours in an oven. Extensive characterizations using scanning electron microscope (SEM) and X-ray diffraction (XRD) were conductedon ZnO powder samples. SEM results showed that hexagonally shaped ZnO micro-nanorods were formed with diameters ranging from hundreds of nanometers to several micrometers. The ZnO sample synthesized at 0.05 M was observedto have a better surface morphological structurethan the 0.1 M sample. In addition, XRD measurements confirmed that samples exhibited a hexagonal crystal structure of ZnO. Moreover, the calculated crystallite sizes of ZnO using the Debye-Scherrer equation using the full-width half maxima of the XRD peaks were 25.153 nm for the 0.05 M sample and 28.707 nm for the 0.1 M sample. The most prominent growth of ZnO had 101 plane orientation or nonpolara-plane followed by nonpolar 100 m-plane and 002 polar c-plane orientations.This studyoffersa simple andlow-costroute to producehigh-quality ZnO micro-nanorods for use in various electrical and optical devices.
Density Profiles, Energy, and Oscillation Strength of a Quantum Dot in Two Dimensions with a Harmonic Oscillator External Potential using an Orbital-free Energy Functional Based on Thomas–Fermi Theory Alfarisa, Suhufa; Dwandaru, Wipsar Sunu Brams; Darmawan, Denny
Makara Journal of Science
Publisher : UI Scholars Hub

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Abstract

This research aims i) to determine the density profile and calculate the ground state energy of a quantum dot in two dimensions (2D) with a harmonic oscillator potential using orbital-free density functional theory, and ii) to understand the effect of the harmonic oscillator potential strength on the electron density profiles in the quantum dot. This study determines the total energy functional of the quantum dot that is a functional of the density that depends only on spatial variables. The total energy functional consists of three terms. The first term is the kinetic energy functional, which is the Thomas–Fermi approximation in this case. The second term is the external potential. The harmonic oscillator potential is used in this study. The last term is the electron–electron interactions described by the Coulomb interaction. The functional is formally solved to obtain the electron density as a function of spatial variables. This equation cannot be solved analytically, and thus a numerical method is used to determine the profile of the electron density. Using the electron density profiles, the ground state energy of the quantum dot in 2D can be calculated. The ground state energies obtained are 2.464, 22.26, 90.1957, 252.437, and 496.658 au for 2, 6, 12, 20, and 56 electrons, respectively. The highest electron density is localized close to the middle of the quantum dot. The density profiles decrease with the increasing distance, and the lowest density is at the edge of the quantum dot. Generally, increasing the harmonic oscillator potential strength reduces the density profiles around the center of the quantum dot.
UV-Visible Optical Absorbance of Graphene Oxide Synthesized from Zinc-Carbon Battery Waste via a Custom-Made Ultrasound Generator based on Liquid Sonication Exfoliation Method Wisnuwijaya, Rhyko Irawan; Purwanto, Agus; Dwandaru, Wipsar Sunu Brams
Makara Journal of Science
Publisher : UI Scholars Hub

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Abstract

The objectives of this study are i) to synthesize graphene oxide (GO) from the waste materials of zinc-carbon (ZnC) batteries via the liquid sonication exfoliation (LSE) method using tweeter piezoelectric probes as speakers, and ii) to study the optical absorbance of the GO produced using a UV-Vis spectrophotometer by varying the mass of the graphite materials obtained from ZnC battery waste. The graphite materials are obtained from the carbon rods of the ZnC batteries, which are ground into powder. The powder is then mixed with distilled water, with powder mass variations of 0.4, 0.6, 0.8, and 1.0 grams. The solutions obtained are sonicated with a frequency of 30 kHz for six hours using a custom-made ultrasound generator based on piezoelectric probes. The effect of graphite material mass variation is studied by observing the UV-Vis spectrophotometer data before and after sonication. The results of this study show absorbance peaks at wavelengths of 221 nm to 227.5 nm, and shouldering peaks at 260 nm to 270 nm, indicating the presence of GO materials for all graphite mass variations. The best GO performances based on the UV-Vis results are obtained in samples with 0.8 and 1.0 grams of graphite powder, which undergo a red shift from 223.5 nm to 227.5 nm, respectively. Scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) are conducted upon the sample of 1.0 grams of graphite powder before and after sonication treatment. The SEM results before sonication show graphite materials forming in large chunks, whereas after sonication smaller islands of GO materials consisting of thin, transparent flakes are observed. The EDX results reveal that the sample material after sonication consists of 88% carbon, 11% oxygen, and a remaining 1% of aluminum, silicon, sulphur, ferrum, and zinc
Co-Authors AGUS PURWANTO Alfarisa, Suhufa Anak Agung Gede Sugianthara Andriani, Nur Baeity Atina, Atina Denny Darmawan Elisabeth Pratidhina Fauzi, Fika Hastuti, Irnawati Widya IMAN SANTOSO Nurohman, Yosi Pratama, Buki Wahyu Pujianto Pujianto Rahmatullah Rahmatullah Safitri, Rika Noor Sari, Dyah Silviana Sari, Emi Kurnia Suhendar, Haris Surya Jatmika Toruan, Parmin Lumban Wisnuwijaya, Rhyko Irawan