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All Journal Jurnal Sains Materi Indonesia Buletin Penelitian Tanaman Rempah dan Obat Bulletin of Chemical Reaction Engineering & Catalysis Journal of Mathematical and Fundamental Sciences Jurnal Kimia dan Kemasan 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 Bulletin of Chemical Reaction Engineering & Catalysis Journal of The Indonesian Society of Integrated Chemistry Rafflesia Journal of Natural and Applied Sciences (RJNAS)
Yoki Yulizar
Departemen Kimia, FMIPA Universitas Indonesia
Agriculture, Biological Sciences & Forestry Astronomy Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Decision Sciences, Operations Research & Management Earth & Planetary Sciences Education Energy Engineering Environmental Science Materials Science & Nanotechnology Mathematics Medicine & Pharmacology Physics Public Health

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Synthesis and Characterization of Gold Nanoparticles (AuNPs) by Utilizing Bioactive Compound of Imperata cylndrica L Iwan Syahjoko Saputra; Siti Suhartati; Yoki Yulizar; Sudirman Sudirman
Jurnal Kimia Terapan Indonesia Vol 22, No 1 (2020)
Publisher : Research Center for Chemistry - LIPI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14203/jkti.v22i1.448

Abstract

Gold nanoparticles (AuNPs) have been successfully synthesized using bioactive compounds of Imperata cylindrica L leaf extract. In this study, precursors used HAuCl4 7x10-4 M, 8x10-4 M and 9x10-4 M. Concentration of Imperata cylindrica L used was 5%. The colloid of Gold nanoparticle (AuNPs) formed were characterized using Ultraviolet-visible Spectrophotometer (UV-Vis), Fourier Transform Infrared Spectroscopy (FTIR), Transmission Electron Microscopy (TEM), X-ray Diffraction (XRD). The formation of gold nanoparticles (AuNPs) at concentration 9x10-4 M showed the best results with a color change to red. UV-Vis showed an absorbance value of 1.4 and a wavelength of 530 nm. FTIR analysis showed the interaction of -OH functional group on phenolic compounds of Imperata cylindrica L leaf extract with Au3+ ions. There was a shift on the peak at wavenumber 3414 cm-1 to 3404 cm-1, indicating the formation of Au nanoparticles. TEM analysis showed the morphology of AuNPs is sphere-shaped with a particle size of 20 nm. XRD analysis showed a crystal size average of gold nanoparticles is 12 nm.
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
Easy Preparation of Zinc Molybdate Photocatalyst and Its Application for Degradation of Methylene Blue Ridla Bakri; Rika Firmansyah; Yoki Yulizar
Jurnal Riset Teknologi Pencegahan Pencemaran Industri Vol. 14 No. 2 (2023): November
Publisher : Balai Besar Standardisasi dan Pelayanan Jasa Pencegahan Pencemaran Industri

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21771/jrtppi.2023.v14.no2.p45-53

Abstract

Photocatalyst is one way that can be done to overcome the problem of dye waste in water. Hazardous chemicals are regularly used in the manufacture of photocatalysts. In this research, ZnMoO4 was prepared by an environmentally friendly and cost-effective synthesis. The functional groups, crystalline structure and morphology of ZnMoO4 were characterised using fourier transform infrared (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM). The band gap energy has been studied through UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS). The photocatalytic activity of ZnMoO4 was tested against the organic pollutant methylene blue under visible light irradiation and its degradation products were analyzed with a UV-Vis spectrophotometer at a wavelength of 664 nm. The photocatalytic process of ZnMoO4 has been able to degrade 99% of methylene blue after 80 minutes of irradiation. The excellent photodegradation performance indicates that the transition activity of electron currents from the valence band to the conduction band on ZnMoO4 is going well.
Co-Authors Adi Nurcahyo Anjar Hermadi Saputro Arief Heru Prianto Dwinna Rahmi Eka Mardika Handayani Foliatini Foliatini Foliatini Foliatini Harits Atika Ariyanta Hitoshi Watarai Indah Puspita Sari Indra Gunawan Iwan Syahjoko Saputra Iwan Syahjoko Saputra Iwan Syahjoko Saputra Iwan Syahjoko Saputra Iwan Syahjoko Saputra Iwan Syahjoko Saputra Lingga Abduracman M Alvien Ghifari Magun Surya Mas Ayu Elita Hafizah Miftah Fauziah Muryanto Muryanto Nerny Wahyuningsih Netti Yulia Ningsih NFN Budiawan Novena Damar Asri Oman Zuas Partomuan Simanjuntak Ridla Bakri Rika Firmansyah Siti Suhartati Siti Suhartati Siti Suhartati Siti Zulaicha, Annisaa Sudirman Sudirman Sudirman Sudirman Sudirman Sudirman Sudirman Sudirman Sudirman Sudirman Sudirman Sudirman Tikarahayu Putri Yogi Nopiandi Permana Yogi Nopiandi Permana Yusuf Zaim Hakim