Papers by Oktaviardi Bityasmawan Abdillah
Journal of Energy Storage
II INTERNATIONAL CONFERENCE “SUSTAINABLE DEVELOPMENT: AGRICULTURE, VETERINARY MEDICINE AND ECOLOGY”
Dalton Transactions
Iron disulfide or pyrite (FeS2) has emerged as a promising transition metal sulfide-based superca... more Iron disulfide or pyrite (FeS2) has emerged as a promising transition metal sulfide-based supercapacitor owing to its abundance and superb electrochemical properties.
Batteries
Li1.2Ni0.13Co0.13Mn0.54O2 (LNCM) has been intensively investigated owing to its high capacity and... more Li1.2Ni0.13Co0.13Mn0.54O2 (LNCM) has been intensively investigated owing to its high capacity and large voltage window. However, despite its high performance, the synthesis of LNCM can be challenging as it usually contains structural disorders and particle-size inhomogeneities, especially via a solid-state method. This work introduces microwave irradiation treatment on the LNCM fabricated via a solid-state method. The as-treated LNCM has low structural disorders, as indicated by the smaller cation mixing, better hexagonal ordering, and higher c/a ratio compared to the non-treated LNCM. Furthermore, the particle-size homogeneities of as-treated LNCM improved, as characterized by scanning electron microscopy (SEM) and particle size analyzer (PSA) measurements. The improved structural ordering and particle-size homogeneity of the treated sample enhances the specific capacity, initial Coulombic efficiency, and rate capability of the cathode material. The LNCM sample with 20 minutes of m...
2022 7th International Conference on Electric Vehicular Technology (ICEVT)
2017 4th International Conference on Electric Vehicular Technology (ICEVT), 2017
Graphene is a two-dimensional material which has interesting properties such as high theoretical ... more Graphene is a two-dimensional material which has interesting properties such as high theoretical surface area, excellent intrinsic strength, high thermal, and electrical conductivity properties. These superior properties make graphene suitable as an anode in a lithium battery. In this research, we introduced copper to enhance electrical conductivity and electrochemical properties of reduced graphene oxide (rGO), since copper has excellent conductivity properties. rGO with the addition of copper has successfully synthesized via in situ chemical exfoliation with microwave-assisted. The resulting samples were characterized by using Fourier Transform Infrared (FTIR), Scanning Electron Microscopy (SEM), four-point probe, and Electrochemical Impedance Spectroscopy (EIS). The annealing treatment could increase the electrical conductivity of the sample. Electrochemical properties of samples have been characterized using Electrochemical Impedance Spectroscopy (EIS), resulting in charge transfer resistance (Rct) value of 48.1 Ohm from the sample of rGO with the addition of 5 wt% copper.
Materials Research Bulletin
IOP Conference Series: Materials Science and Engineering
Graphene has been gaining immense attention from scientists over the world for its exceptional pr... more Graphene has been gaining immense attention from scientists over the world for its exceptional properties, which makes it promising for several applications such as energy storage, electronic devices, and biomedicine. Graphene synthesis via the electrochemical exfoliation route offers a cheap, simple, eco-friendly, and scalable process for industrial purposes. In this work, the effect of voltage bias during electrochemical exfoliation on the electrical properties and yield of the obtained exfoliated graphene (EG) was studied. Graphite sheet as raw material was pre-treated by immersing it into H2SO4/H2O2 mixture before the electrochemical process. By applying the optimum voltage of 10 V, the electrochemical method was able to produce EG with yield as high as 40.95% in a relatively shorter time. Moreover, EG also demonstrated the highest electrical conductivity of 25.45 S/cm.
RSC Advances
Early expansion of graphite after H2SO4/H2O2 pre-treatment and cyclic voltammograms of exfoliated... more Early expansion of graphite after H2SO4/H2O2 pre-treatment and cyclic voltammograms of exfoliated graphite (EG) prepared with various volume fractions of H2O2.
2018 5th International Conference on Electric Vehicular Technology (ICEVT), 2018
Graphene is one of the materials that is widely studied as the anode of the lithium-ion battery. ... more Graphene is one of the materials that is widely studied as the anode of the lithium-ion battery. Electrochemical exfoliation is one of the eco-friendly and high scalability methods for graphene production that is suitable in industrial scale. However, the low yield issue needs to be addressed. Herein, we use a graphite rod electrode that pre-treated with H2SO4/H2O2 mix solution to generate higher yield and performance of graphene as the electrode material. The Fourier transform infrared (FTIR) showed that the oxidation of graphite during electrochemical exfoliation process increased with the increase of H2O2 concentration during the pretreatment process. The four-point probe and Electrochemical Impedance Spectroscopy (EIS) characterization shows the sample with pre-treatment using H2O2 of 5 vol % yield the highest conductivity of 1124 S/m and lowest Rct of 43.8 Ohm.
Journal of Physics: Conference Series, 2021
In this study, the electrical properties of exfoliated graphite (EG) with copper addition is repo... more In this study, the electrical properties of exfoliated graphite (EG) with copper addition is reported. Firstly, EG samples were synthesized using electrochemical exfoliation of the pre-treated graphite sheet then combined with various copper concentrations. X-Ray Diffraction (XRD) characterization indicated that the composites of EG, Cu, and Cu2O were formed. A higher Cu2O amount obtained when the higher concentration of copper precursor was added in the EG. Scanning Electron Microscopy (SEM) images showed that more particles with larger sizes were anchored on the EG surface as higher copper concentration. The electrical properties of the samples were measured using the four-point probe method. The highest electrical conductivity of 37.86 S/cm was produced in the EG sample with 1 wt.% of copper addition. The result reveals that the optimum copper addition can increase the electrical properties of EG.
2019 6th International Conference on Electric Vehicular Technology (ICEVT)
POSITRON
In this work, the photocatalytic performance of electrochemically exfoliated graphite (EG) with l... more In this work, the photocatalytic performance of electrochemically exfoliated graphite (EG) with low copper addition (≤ 5 wt.%) was studied. Composites of EG/Cu/Cu2O were successfully prepared by microwave-assisted in situ reduction method. FTIR spectra of the samples showed that the main functional groups of graphite were detected in the samples. XRD characterization further proved the presence of EG, Cu, and Cu2O in the samples. The higher proportion of Cu2O presented in the samples prepared with a higher amount of Cu2+. SEM analysis showed that Cu2O/Cu particles were homogeneously deposited on the surface of EG. The composites of EG, Cu, and Cu2O with a varied amount of Cu (1 and 5 wt. %) in EG / Cu2+ mixture were examined as photocatalyst in the degradation process of Rhodamine B (RhB). The photocatalytic degradation of RhB was analysed by observing its decolorization within a set time of irradiation. UV-Vis analysis revealed that the degradation of RhB in EG/Cu/Cu2O A and B for ...
New Journal of Chemistry
The possible explanations on how the existence of copper, CuO, or Cu2O influences the electrical ... more The possible explanations on how the existence of copper, CuO, or Cu2O influences the electrical conductivity and electrochemical properties of rGO.
Abstrak Praktikum ini bertujuan untuk menentukan warna pendaran dan panjang gelombang masing-masi... more Abstrak Praktikum ini bertujuan untuk menentukan warna pendaran dan panjang gelombang masing-masing warna yang dihasilkan oleh karbon nanodots. Karbon nanodots adalah partikel karbon yang memiliki diameter berukuran nano yaitu berukuran antara 1-10 nanometer. Partikel ini mampu memendarkan cahaya ketika disinari oleh sinar UV dengan panjang gelombang emisi atau warna pendarab cahaya bergantung pada lebar celah pita karbon nanodots. Ketika elektron berada dalam keadaan eksitasi, elektron akan tertarik untuk kembali mengisi hole pada pita valensi akibat adanya gaya Coulomb. Saat kembali ke pita valensi, elektron akan mengemisikan energi dalam bentuk foton. Hal ini yang membuat karbon nanodot dapat memendarkan cahaya. Sintesis karbon nanodots pada praktikum ini menggunakan metode microwave heating. Bahan yang digunakan ialah urea dan asam sitrat yang dilarutkan. Konsentrasi dan waktu pemanasan divariasikan untuk mengetahui pengaruhnya terhadap warna pendaran yang dihasilkan. Campuran urea dan asam sitrat dipanaskan terleih dahulu menggunakan oven, setelah itu dipindahkan ke microwave. Setelah itu, sampel disinari menggunakan sinar UV untuk melihat terjadi tidaknya pendaran warna. Sampel paling baik untuk menunjukkan pendaran yaitu yang megandung 0,035 gram asam sitrat dan dipanaskan melalui microwave selama 120 detik. Selain itu dapat disimpulkan bahwa semakin tinggi konsentrasi asam sitrat, semakin rendah panjang gelombang emisi yang dihasilkan. Kata kunci : emisi, karbon nanodots, luminescence, pendaran, pengurungan kuantum
Teaching Documents by Oktaviardi Bityasmawan Abdillah
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Papers by Oktaviardi Bityasmawan Abdillah
Teaching Documents by Oktaviardi Bityasmawan Abdillah