Article Per Year (5 Year)
p-Index From 2020 - 2025
0.444
P-Index
This Author published in this journals
All Journal Jurnal Kimia Riset Makara Journal of Science Jurna Beta Kimia
Djulia Onggo
Inorganic and Physical Chemistry Research Division, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jl. Ganesa 10 Bandung 40132
Chemical Engineering, Chemistry & Bioengineering Chemistry Education

Published : 3 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 3 Documents
Search

 1 
CRYSTAL STRUCTURE OF [Bis(DIMETHYLFORMAMIDE) Bis(2,2’-PYRIDYL)QUINOLINE)IRON(II)]Bis-(TETRAPHENYLBORATE) Jahro, Iis Siti; Onggo, Djulia; Ismunandar, Ismunandar; Rahayu, Susanto Imam; Yamin, Bohari M.
Makara Journal of Science Vol. 13, No. 2
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

The goal of this research is to obtain single crystal and structural information of iron(II) complex with 2,(2’- pyridyl)quinoline(pq) ligands. The reaction of iron(II) salt with 2,(2’-pyridyl)quinoline ligand and sodium tetraphenylborate in the molar ratio of 1:3:2 in methanol-N,N-dimethylformamide(dmf) solution results in an iron(II) complex. The formula of the [Fe(pq)2(dmf)2](BPh4)2 complex has been obtained from the iron(II) and C, H, N contents. Single crystal of [Fe(pq)2(dmf)2](BPh4)2 suitable for X-ray investigation was obtained by evaporation of the complex solution in N,N-dimethylformamide at room temperature after 24 hours. This compound crystallizes in monoclinic system with C2/c space group, a = 27.950(4), b = 14.169(7), c = 17.717(9) Å and β = 105.669(11)°. The structure consist of iron(II) is chelated by two pq ligands through the N atoms and two dmf molecules in a six-coordination environment. The charge of the [Fe(pq)2(dmf)2] 2+ cation is balanced by two tetraphenylborate (BPh4) - anions.
Sintesis Kompleks [Fe(Htrz)2(trz)]X dari [Fe(Htrz)2(trz)]BF4 dengan X= PF6- dan B(C6H5)4- Apolonia, Maria Novansia; Onggo, Djulia; Nay, Dorthea Maria Woga; Boikh, Mesakh T.W.; More, Evanisia T.W.
Jurnal Beta Kimia Vol 4 No 1 (2024): Volume 4, Nomor 1: Mei 2024
Publisher : Universitas Nusa Cendana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35508/jbk.v4i1.15455

Abstract

Senyawa spin crossover merupakan senyawa unik yang menjadi pusat perhatian untuk diteliti beberapa tahun terakhir. Sifat peralihan menjadikan senyawa tersebut digunakan untuk aplikasi praktis dalam sensor termal dan tekanan serta perangkat optik. Pada penelitian ini, kompleks [Fe(Htrz)2(trz)]BF4, [Fe(Htrz)2(trz)]PF6 dan [Fe(Htrz)2(trz)]B(C6H5) telah berhasil disintesis. Kompleks [Fe(Htrz)2(trz)] BF4 berwarna ungu pada suhu kamar menunjukkan keadaan spin rendah (diamagnetik), bila dipanaskan kompleks ini berubah menjadi warna putih (paramagnetik). Kompleks [Fe(Htrz)2(trz)]PF6 dan [Fe(Htrz)2(trz)]B(C6H5)4 masing-masing disintesis dengan menambahkan garam alkali KPF6 dan NaB(C6H5)4 berlebih ke Fe(BF4)2.6H2O dan Htrz sebelum terbentuknya endapan, sehingga anion PF6- dan B(C6H5)4- dapat mendorong BF4- keluar dari kompleks [Fe(Htrz)2(trz)]BF4. Kompleks [Fe(Htrz)2(trz)]B(C6H5)4 berwarna ungu (diamagnetik) pada suhu kamar dan bila dipanaskan hingga suhu lebih dari 100 °C berubah menjadi putih (paramagnetik). Sedangkan kompleks [Fe(Htrz)2(trz)]PF6 berwarna putih (paramagnetik) pada suhu kamar, ketika didinginkan hingga di bawah suhu nol derajat kompleks ini berubah warna menjadi ungu (diamagnetik). Data karakterisasi EDS mendukung hasil percobaan dimana anion PF6- dan B(C6H5)4- berhasil menggantikan anion BF4- sehingga sesuai rumus kimia kompleksnya adalah [Fe(Htrz)2(trz)]PF6 dan [Fe(Htrz)2(trz)](C6H5)4.
Tuning the Electrical Conductivity of Bacterial Cellulose Membranes by Multi-Walled Carbon Nanotube Insertion as Bio-Nanocomposite Conductive Materials Joris, Shielda Natalia; Onggo, Djulia
Jurnal Kimia Riset Vol. 10 No. 2 (2025): December
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkimris.v10i2.79423

Abstract

Bacterial cellulose (BC) obtained from nata-de-coco represents a sustainable biopolymer that offers broad potential as a platform for functional material development. In this work, the electrical performance of BC was improved through the incorporation of multi-walled carbon nanotubes (MWCNTs), which were dispersed in a cetyltrimethylammonium bromide (CTAB) solution prepared at a 1:1 mass ratio. The resulting composite membranes were examined using four-point probe measurements, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The electrical conductivity increased from 0.2 S cm⁻¹ to 1.2 S cm⁻¹ as immersion time was extended, reaching an optimum after six days, which was attributed to better nanotube dispersion and alignment inside the cellulose fibril matrix. SEM and thermal analyses confirmed the gradual integration of MWCNTs into the BC framework. The findings demonstrate that adjusting the insertion duration of nanotubes can effectively modulate the electrical properties of BC membranes, supporting their potential as green bio-nanocomposites for emerging energy and electronic technologies.
Co-Authors Apolonia, Maria Novansia Bohari M. Yamin Boikh, Mesakh T.W. Iis Siti Jahro Ismunandar Joris, Shielda Natalia More, Evanisia T.W. Nay, Dorthea Maria Woga Susanto Imam Rahayu