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All Journal JURNAL KIMIA SAINS DAN APLIKASI Jurnal Sains Materi Indonesia Buletin Penelitian Tanaman Rempah dan Obat Journal of Mathematical and Fundamental Sciences Jurnal Kimia dan Kemasan Science and Technology Indonesia Jurnal Penelitian Pendidikan IPA (JPPIPA) Jurnal Kimia Terapan Indonesia Indonesian Journal of Chemistry Acta Chimica Asiana Buletin Penelitian Tanaman Rempah dan Obat Jurnal Riset Teknologi Pencegahan Pencemaran Industri Jurnal Kimia dan Kemasan Makara Journal of Science Environmental and Materials Bulletin of Chemical Reaction Engineering & Catalysis Journal of The Indonesian Society of Integrated Chemistry Rafflesia Journal of Natural and Applied Sciences (RJNAS) Jurnal Sains Materi Indonesia Helium: Journal of Science and Applied Chemistry
Yoki Yulizar
Department Of Chemistry, Faculty Of Mathematics And Natural Sciences, Universitas Indonesia
Agriculture, Biological Sciences & Forestry Astronomy Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Control & Systems Engineering Decision Sciences, Operations Research & Management Earth & Planetary Sciences Education Energy Engineering Environmental Science Industrial & Manufacturing Engineering Materials Science & Nanotechnology Mathematics Medicine & Pharmacology Physics Public Health

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Theoretical Analysis of Interaction Energy in Alginate-Capped Gold Nanoparticles Colloidal System Foliatini Foliatini; Yoki Yulizar; Mas Ayu Elita Hafizah
Indonesian Journal of Chemistry Vol 14, No 3 (2014)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (285.143 KB) | DOI: 10.22146/ijc.21234

Abstract

Stability of Au/alginate nanocomposite was theoretically evaluated by computing various interactions energy which contributes in the system, including attraction and repulsion interaction. The results revealed that both polymer and electrostatic charges played a significant role in the stabilization, but the steric repulsion comes from polymer chain is a more effective stabilization mechanism than the electrostatic repulsion. Higher pH yielded in stronger electrostatic repulsion but when the alginate thickness is low the resulting nanocomposite was less stable in a long time period. Interaction energies for Au/alginate nanocomposite colloidal system was up to ~60 kT for alginate thickness of 1 nm, at very short particle-particle separation distance (< 1 nm). As the alginate thickness can be controlled by adjusting the alginate concentration, it can be concluded that the high stability of Au/alginate nanocomposite can be achieved by employing an appropriate amount of alginate concentration.
Green Synthesis of Carbon Nanotubes from Coconut Shell Waste for the Adsorption of Pb(II) Ions Yusuf Zaim Hakim; Yoki Yulizar; Adi Nurcahyo; Magun Surya
Acta Chimica Asiana Vol. 1 No. 1 (2018)
Publisher : Chemistry Education Program, the University of Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (409.683 KB) | DOI: 10.29303/aca.v1i1.2

Abstract

Numerous complex methods have been developed for the preparation of carbon nanotubes (CNT) such as laser vaporization, arc discharge, pyrolysis, and chemical vapour deposition (CVD). In this study, an environmentally friendly and convenient method called one-step water assisted (quenching) synthesis method was conducted from graphite flakes, which were taken from coconut shell wastes to produce carbon nanotubes. Chemical and physical structure of the carbon nanotubes were characterized by FTIR (Fourier Transform Infrared), Scanning Electron Microscope (SEM), and Transmission Electron Microscopy (TEM). Adsorption performance of heavy metals Pb(II) ions by CNTs has been evaluated using the stirring method, and the concentration of Pb(II) ions has been determined using Atomic Absorption Spectroscopy (AAS). The adsorption conditions such as pH and contact time have been obtained. The results showed that carbon nanotubes were a bit successfully formed, in which the tubes distribution are scattered irregularly. The average tube diameter was 123 nm. During the adsorption test, it was found that the adsorption was proportional to the contact time, in which the optimum contact time was 20 minutes. The optimum pH of Pb(II) ions absorption was 5 where the potential for Pb(II) ions absorption was 120 %. The results indicate the true potential of this green chemistry based method, and it opens the chance for possibility to produce carbon nanotubes at a larger scale.
Sintesis CeVO4 Menggunakan Metode Sol Gel dengan Ekstrak Daun Kasingsat (Senna occidentalis (L.) Link): Karakterisasi dan Aktivitas Fotokatalitik pada Iradiasi Cahaya Tampak Eka Mardika Handayani; Muryanto Muryanto; Oman Zuas; Yoki Yulizar
Jurnal Penelitian Pendidikan IPA Vol 8 No 4 (2022): October
Publisher : Postgraduate, University of Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/jppipa.v8i4.1764

Abstract

CeVO4 as visible light driven photocatalyst was synthesized using Senna occidentalis (L.) Link leaves extract (SOE) by sol-gel method which can increase the degradation of malachite green (MG) under visible irradiation. The products were characterized using Fourier Transform Infrared Spectrophotometer (FTIR), X-ray Diffraction (XRD), and Field Emission Scanning Electron Microscope Energy Dispersive Spectroscopy (FESEM-EDS). UV–Vis Diffuse Reflectance Spectrophotometer (UV–Vis DRS) absorption spectrum indicated that the band gap of the CeVO4 is about 2,76 eV, and XRD patterns of the samples were indexed to tetragonal zircon type CeVO4 structure. Photocatalytic activity of the synthesized CeVO4 nanoparticles was evaluated for degrading the MG under visible light irradiation, showing as an active catalyst on photodegradation of the MG up to 77% under experimental condition of this study.
Green Synthesis of Gold Nanoparticles using Aqueous Garlic (Allium sativum L.) Extract, and Its Interaction Study with Melamine Yoki Yulizar; Harits Atika Ariyanta; Lingga Abduracman
Bulletin of Chemical Reaction Engineering & Catalysis 2017: BCREC Volume 12 Issue 2 Year 2017 (August 2017)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.12.2.770.212-218

Abstract

Gold nanoparticles (AuNPs) have been successfully prepared by green synthesis method using aqueous extract of garlic with the Latin name of Allium sativum L. (ASL) as a reducing and stabilizing agents. Identification of active compounds in aqueous ASL extract was conducted by phytochemical analysis and Fourier transform infrared (FTIR) spectroscopy, while the synthesized AuNPs were characterized using UV-Vis spectrophotometer and transmission electron microscopy-selected area electron diffraction (TEM-SAED). The AuNPs formation was optimized at aqueous ASL extract concentration of 0.05%, HAuCl4 concentration of 2.0×10-4 M, and pH of 3.6. The optimized AuNPs was characterized   using TEM, and has a spherical shape with particle size of 15±3 nm. The particles were also stable up until one month. The synthesized AuNPs has been studied its interaction with melamine, and showed the optimum pH of interaction at 3.6. 
Modifikasi Bentonit Terpilar Al dengan Polianilin Sebagai Reduktor Ion Cr (VI) Netti Yulia Ningsih; Yoki Yulizar
Journal of The Indonesian Society of Integrated Chemistry Vol. 6 No. 2 (2014): Journal of The Indonesian Society of Integrated Chemistry
Publisher : Pendidikan Kimia FKIP Universitas Jambi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22437/jisic.v6i2.1940

Abstract

Bentonit merupakan salah satu mineral yang kelimpahannya cukup besar di Indonesia. Untuk meningkatkan daya guna bentonit maka dibuat bentonit terpilar Al dengan polianilin dan diaplikasikan sebagai agen pereduksi ion Cr(VI). Pengukuran dengan XRD menunjukkan pilarisasi dengan polikation Al menyebabkan basal spacing dari bentonit naik menjadi 18,41413 Ã…. Sintesis Bent@Al@PANI dilakukan secara in situ dengan perbandingan konsentrasi APS/anilin adalah 1,25. Hasil uji FTIR dan spektrofotometer UV-Vis mengindikasikan bahwa polianilin yang diperoleh merupakan bentuk emeraldin salt (ES). Dari pengolahan data persentase 0,1 g Bent@Al@PANI 0,05 M dengan waktu reaksi 10 menit, pH 3,0 mampu mereduksi Cr(VI) 1,92x10-4 M sebesar 89,92%. Kata kunci: bentonit, basal spacing, reduksi Cr(VI), polianilin
Green Synthesis Nanopartikel Perak (AgNPs) Menggunakan Bioreduktor Alami Ekstrak Daun Ilalang (Imperata cylindrica L) Annisaa Siti Zulaicha; Iwan Syahjoko Saputra; Indah Puspita Sari; M Alvien Ghifari; Yoki Yulizar; Yogi Nopiandi Permana; Sudirman Sudirman
RAFFLESIA JOURNAL OF NATURAL AND APPLIED SCIENCES Vol. 1 No. 1 (2021): April
Publisher : UNIB Press

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33369/rjna.v1i1.15588

Abstract

Ilalang (Imperata cylindrica L) merupakan tumbuhan liar yang jarang dimanfaatkan. Daun ilalang mengandung senyawa bioaktif seperti alkaloid dan flavonoid. Senyawa flavonoid dapat digunakan sebagai zat reduktor alami dalam sintesis nanopartikel perak (AgNPs). Tujuan pada penelitian ini adalah sintesis nanopartikel perak menggunakan bioreduktor alami dari ekstrak daun ilalang. Sintesis nanopartikel perak menggunakan metode green synthesis (reduktor alam). Terbentuknya koloid nanopartikel perak terlihat secara visual ditandai dengan perubahan warna koloid menjadi coklat setelah penambahan ekstrak daun ilalang. Hasil UV-Vis menunjukkan nanopartikel perak memiliki puncak serapan pada panjang gelombang 420 nm dengan nilai absorbansi 1,9. FTIR memperlihatkan spektrum pengurangan puncak serapan nanopartikel perak pada bilangan gelombang 3356 cm-1. Hasil XRD dan PSA menunjukkan nanopartikel perak memiliki rata-rata ukuran kristal 19 nm dan distribusi ukuran partikel sebesar 1160 nm. Nanopartikel perak memiliki bentuk bulat dengan ukuran partikel 20 nm yang terlihat pada morfologi hasil TEM
Microwave-Assisted Synthesis of Alginate-Stabilized Gold Nanoparticles Foliatini, Foliatini; Yulizar, Yoki; Hafizah, Mas Ayu Elita
Makara Journal of Science Vol. 18, No. 4
Publisher : UI Scholars Hub

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Abstract

during boreal summer to fall 2011. In this study, data from satellite observations and atmospheric reanalysis datasets
Investigation on the Synergistic Complexation of Ni(II) with 1,10-Phenanthroline and Dithizone at Hexane-Water Interface Using Centrifugal Liquid Membrane-SpectrophotometryInvestigation on the Synergistic Complexation of Ni(II) with 1,10-Phenanthroline and Dithizone at Hexane-Water Interface Using Centrifugal Liquid Membrane-Spectrophotometr Yulizar, Yoki; Wahyuningsih, Nerny; Asri, Novena Damar; Watarai, Hitoshi
Makara Journal of Science Vol. 16, No. 3
Publisher : UI Scholars Hub

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Abstract

Complex formation of Ni(II) and 1,10-phenanthroline (C12H8N2/Phen) with the addition of dithizone (C13H12N4S/HDz) at the hexane-water interface has been studied by direct measurement spectrophotometry using the centrifugal liquid membrane (CLM) method. Ni(II) ion with Phen formed a cationic complex of Ni(C12H8N2)2 2+ or NiPhen2 2+. That complex dissolved in the aqueous phase and had two UV absorption spectrum maxima wavelengths, λmax 270 and 292 nm. Observation of complex formation was performed variations of pH and ligand concentration. The pH caused protonation that affected the amount of the formed complex. With the variations of ligand concentrations, the greater was the concentration of ligands the greater was the formed complex. Based on the Batch method, the HDz ligand addition into the NiPhen2 2+ cationic complex produced ion association complex of Ni(C13H11N4S)2(C12H8N2) or NiDz2Phen at λmax 403 nm, and was extracted in the organic phase. Measurement results using CLM method showed that NiDz2Phen complex was formed at hexane-water interface with λmax 523 nm. Comparison of Phen with HDz ligand concentrations affected the initial formation rate of NiDz2Phen complex. The greater concentration of Phen ligand increased the initial rate of formation for synergistic complex. The obtained data using CLM method indicated that the synergistic complex formation rate constant of NiDz2Phen at the interface, k was 0.30/s.
Synthesis of gold nanoparticles with allicin to modify boron-doped diamond surface for oxygen sensor applications Raharto, Toto; Setiyanto, Cahya Mukti; Ariyanta, Harits Atika; Nahda, Dinda Prastika Nabila; Hani, Adinda Muthia; Yulizar, Yoki; Ivandini, Tribidasari Anggraningrum; Einaga, Yasuaki
Environmental and Materials Vol. 1 No. 2: (December) 2023
Publisher : Institute for Advanced Science, Social, and Sustainable Future

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.61511/eam.v1i2.2023.560

Abstract

Modification of surface of boron-doped diamond (BDD) film with gold nanoparticles (AuNPs) was carried out to increase its catalytic activity for an application as an oxygen sensor. Allicin was isolated from garlic by salting out extraction technique, and then used as the capping agent to synthesize AuNPs as it has a double bond structure that could be reacted to attach the BDD surface under UV light radiation. An average size of AuNPs at around 46,00 ± 9,06 nm was obtained, while the modification of the BDD surface by the synthesized AuNPs indicated that the surface of BDD could be covered by gold at around 0.6 % (w/w). Investigation of the AuNPs-modified BDD as a working electrode for the oxygen reduction by using cyclic voltammograms in 0.1 M phosphate buffer solution pH 7 observed a current peak at around -0.45 V (vs. Ag/AgCl). The current of this peak linearly increased proportionally to the dissolved oxygen concentrations (R2=0.9986). Moreover, a limit of detection of the dissolved oxygen of 0.12 ppm and limit of quantity 0.41 ppm could be achieved with excellent stability at 6.86% RSD with 6 repetitions and sensitivity at 19.086 μA/ppm indicated that the modified BDD is promising for applications as an oxygen sensor.
Preparation and Characterization of ZnO-Fe2O3 Nanocomposite Using Green Synthesis Method and Its Application in Powder Pyrotechnics Lestariana, Evie; Supriyatno, Heru; Sitompul, Hamonangan Rekso Diputro; Restasari, Afni; Yulizar, Yoki
Science and Technology Indonesia Vol. 10 No. 2 (2025): April
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2025.10.2.493-503

Abstract

Nanocomposites are often used as a catalyst in the pyrolysis of Al/Mg/KNO3 rocket igniter charge. Because the synthesis of the nanocomposites has a negative impact on the environment, in this study, the nanocomposite of ZnO-Fe2O3 was synthesized using a green synthesis method based on the aqueous fraction of Syzygium polyanthum (Wight) Walp. leaf extract. The secondary metabolites contained in the extract were tested. ZnO-Fe2O3 nanocomposite was characterized using Ultra-Violet-Visible Diffuse Reflectance Spectroscopy (UV Vis-DRS), Fourier Transform Infra-Red Spectroscopy (FT-IR), X-ray Diffraction (XRD), Particle Size Analyzer (PSA), Scanning Electron Microscope-Energy Dispersive X-Ray Spectroscopy (SEM-EDS), and Transmission Electron Microscope (TEM).The thermal decomposition process of Al/Mg/KNO3 with and without ZnO-Fe2O3 nanocomposite was analyzed using Differential Thermal Analysis (DTA) and Thermogravimetry Analysis (TGA). As a result, ZnO-Fe2O3 nanocomposite is successfully synthesized, proven by UV-Vis DRS, FT-IR, XRD, and SEM-EDS analysis. It highlights the effectiveness of aqueous leaves extract of Syzygium polyanthum (Wight) Walp. as a capping agent because of the secondary metabolites. Based on PSA and TEM characterization, the particle size is 17.37 nm. The TGA curves demonstrate that the addition of ZnO-Fe2O3 nanocomposite lowers the activation energy for decomposition of Al/Mg/KNO3, from 58.71 kJ/mol to 52.07 kJ/mol, as well as reduces the stage in the decomposition process. A particular reason lies on the role of ZnO-Fe2O3 nanocomposite in reducing the activation energy of the thermal decomposition ofKNO3.
Co-Authors Adawiah Adawiah Adi Nurcahyo Aida R. Pudjiastuti Anjar Hermadi Saputro Arief Heru Prianto Armi Wulanawati Asri, Novena Damar Destia Puteri Ananda, Destia Dewi Tristantini Dianursanti Dwinna Rahmi Einaga, Yasuaki Eka Fitriani Ahmad Eka Mardika Handayani Eny Kusrini Fadli Rohman Firmansyah, Rika Foliatini Foliatini Foliatini Foliatini Ghifari, M Alvien Hani, Adinda Muthia Harits Atika Ariyanta Harits Atika Ariyanta Heru Supriyatno Hitoshi Watarai Indah Puspita Sari Indra Gunawan Ivandini Tribidasari Anggraningrum Iwan Syahjoko Saputra Iwan Syahjoko Saputra Iwan Syahjoko Saputra Iwan Syahjoko Saputra Iwan Syahjoko Saputra Iwan Syahjoko Saputra Julinton Sianturi Katharina Oginawati Lestariana, Evie Lingga Abduracman Magun Surya Mas Ayu Elita Hafizah Miftah Fauziah Munir, Muhammad Miftahul Muryanto Muryanto Nahda, Dinda Prastika Nabila Nerny Wahyuningsih Netti Yulia Ningsih NFN Budiawan Ng Sha Shiong Novena Damar Asri Oman Zuas Partomuan Simanjuntak Puji Lestari Raharto, Toto Restasari, Afni Ridla Bakri Rita Arbianti Setiyanto, Cahya Mukti Siti Suhartati Siti Suhartati Siti Suhartati Siti Zulaicha, Annisaa Sitompul, Hamonangan Rekso Diputro Slamet . Sri Mulijani Sudirman Sudirman Sudirman Sudirman Sudirman Sudirman Sudirman Sudirman Sudirman Sudirman Sudirman Sudirman Sudirman Tikarahayu Putri Tresye Utari, Tresye Virleenda M. Setianingrum Wahyuningsih, Nerny Watarai, Hitoshi Yogi Nopiandi Permana Yogi Nopiandi Permana Yosmarina Harahap Yusuf Zaim Hakim