Article Per Year (5 Year)
p-Index From 2020 - 2025
0.408
P-Index
This Author published in this journals
All Journal Indonesian Journal of Chemistry
Wega Trisunaryanti
Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Sekip Utara, 55281 Yogyakarta, Indonesia
Chemical Engineering, Chemistry & Bioengineering Chemistry

Published : 2 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 2 Documents
Search

 1 
The Influence of Permanganate Enhancement to Graphite on Chemical Structure and Properties of Graphene Oxide Material Generated by Improved Tour Method Dyah Ayu Fatmawati; Triyono Triyono; Wega Trisunaryanti; Haryo Satriya Oktaviano; Uswatul Chasanah
Indonesian Journal of Chemistry Vol 21, No 5 (2021)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.57423

Abstract

Synthesis of graphene oxide (GO) material with variations in permanganate/graphite ratio has been carried out. This research purposes to study the impact of increasing oxidizing agents to graphite on the chemical structure and properties of the GO material produced. All GOs were synthesized using the improved Tour method with three variations of permanganate/graphite ratios of 5, 6, and 7. The results obtained include GO-5, GO-6, and GO-7, respectively, having a d spacing value of 0.843; 0.891; 0.894 nm by XRD analysis and 0.768; 0.756; 0.772 nm by SAED analysis. Based on the FTIR data, all GO materials bring up the peaks of oxygen-functionalized carbon absorption such as O–H, C–H sp3, C=O, C–O–C of ether and ester, and C-OH for carboxylic acids and alcohols. The oxidation levels (O/C ratio taken from EDX data) of GO-5, GO-6, and GO-7 are 0.67, 0.88, and 1.50, respectively. SEM images display the appearance of an exfoliated layer with a wrinkled and irregular surface. TEM images show thin and transparent layers. The main peaks with the highest absorbance at the wavelength around 230-240 nm, meanwhile the band gap energy produced was 3.53; 3.71; 3.55 eV for GO-5, GO-6, and GO-7, respectively.
The Effects of Manganese Dopant Content and Calcination Temperature on Properties of Titania-Zirconia Composite Muhamad Imam Muslim; Rian Kurniawan; Mokhammad Fajar Pradipta; Wega Trisunaryanti; Akhmad Syoufian
Indonesian Journal of Chemistry Vol 21, No 4 (2021)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.61900

Abstract

The effects of dopant content and calcination temperature on Mn-doped TiO2-ZrO2 structure and properties were successfully investigated. Composite of Mn-doped titania-zirconia was synthesized by sol-gel method. Titanium(IV) isopropoxide was used as the precursor of TiO2, while zirconiapowder was used as another semiconductor. MnCl2∙4H2O was used as the source of dopant in this study. Various amounts of manganese were incorporated into TiO2-ZrO2 and calcination was performed at temperatures of 500, 700 and 900 °C. Synthesized composites were characterized by Fourier-transform infrared spectroscopy (FTIR), specular reflectance UV-Vis spectroscopy (SR UV-Vis), X-ray diffraction method (XRD) and scanning electron microscopy equipped with X-ray energy dispersive spectroscopy (SEM-EDX). The results showed that Mn-doped TiO2-ZrO2 with the lowest bandgap (2.78 eV) was achieved with 5% of Mn dopant and calcined at 900 °C, while Mn-doped TiO2-ZrO2 with the highest bandgap (3.12 eV) was achieved with 1% of Mn dopant content calcined at 500 °C.
Co-Authors Akhmad Syoufian Dyah Ayu Fatmawati Haryo Satriya Oktaviano Mokhammad Fajar Pradipta Muhamad Imam Muslim Rian Kurniawan Triyono Triyono Uswatul Chasanah