cover
Contact Name
I Wayan Sutapa
Contact Email
wayansutapa@uho.ac.id
Phone
+6281343001979
Journal Mail Official
wayansutapa@uho.ac.id
Editorial Address
Kampus Hijau Bumi Tridharma, Anduonohu, Kec. Kambu
Location
Kota kendari,
Sulawesi tenggara
INDONESIA
International Journal of Acta Material
Published by Universitas Halu Oleo
ISSN : -     EISSN : 30642396     DOI : https://doi.org/10.62749/ijactmat
Core Subject : Science,
The International Journal of Acta Material (Int. J. Act. Mat) is a bulletin for publishing original and complete papers, short communications as well as review results which aim to disseminate study results (Theoretical or Experiment) to explore of the relationship between processes, structures and properties of the frontier solid and liquid materials. The papers that have the potential for high impact and/or substantially advance the field will be sought. The process studied includes a series of material formation/manufacturing which will be achieved with the instrumentation used. The Journal also addresses a wide variety of subjects that are vital to the field, including but not limited to: Catalysis Material, Membrane Material, Solar cell, Condensed-matter physics, Electronics and device physics material, Absorbent Material, Green chemistry, Information theory and computation material, Nanomaterial, Polymer Material, Quantum physics and quantum technologies, Supramolecular material, Surface chemistry, Theoretical chemistry/physic solid material, Biofuel, Biomass Material.
Articles 31 Documents
Analysis of Water Quality in Sea Waters After The Sea Snot Occurrence in Bima Bay West Nusa Tenggara S. Kasim; N. A. Pratiwi; H. Natsir; S. Liong; I W. Sutapa
International Journal of Acta Material Vol. 1 No. 2 (2025): February 2025
Publisher : Faculty Mathematics and Natural Sciences, Halu Oleo University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.62749/ijactmat.v1i2.12

Abstract

The incident that occurred in April 2022 in Bima Bay was a phenomenon that shocked the residents of Bima City and outside the Bima area. Based on previous laboratory tests, the cause is Sea Snot which is accompanied by an explosion in the number and metabolism of algae. The entry of organic and inorganic pollutants into water bodies can cause water quality to experience degradation in biological function. This research aims to analyze water quality in marine waters with the parameters BOD, COD, DO, determine the Nitrate and Phosphate content and characterize total coliform and E. coli bacteria in marine waters. This research uses electrometric, photometric and membrane filtrate methods. pH ranged from 7.85 - 8.22; DO levels 5.97 - 6.15 mg / L, BOD 1.3, and 5 ranged from 5.52 - 9.06 mg / L. COD levels 15.62 - 21.44 mg / L. Nitrate ranges from 0.124 - 0.204 mg/L. Phosphate ranges from 0.27 - 0.41. Total coliform bacteria ranges from 706 - 1,266 colonies/100 mL and E. coli 0.75 - 1.75 colonies/100 mL. The water quality in the sea waters of Bima Bay has mostly met the sea water quality standards for the parameters BOD, DO, total coliform, E. coli , while the COD parameter is not included in the mandatory parameters which are one of the indicators of sea water pollution. The content of Nitrate and Phosphate in the waters of Bima Bay shows that its value has exceeded the sea water quality standards.
Effect of Ni Content Variation on the Synthesis of Nickel-Mobile Crystalline Material-41 (Ni-MCM-41) for Methylene Blue Adsorption L. O. Ahmad; H. Hidayat; A. Zaeni; F. Muhamad
International Journal of Acta Material Vol. 1 No. 2 (2025): February 2025
Publisher : Faculty Mathematics and Natural Sciences, Halu Oleo University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.62749/ijactmat.v1i2.13

Abstract

The research studied the enhancement of thermal resistance and the increase of adsorption capacity of methylene blue dye by Ni-doped mesoporous MCM-41 adsorbent (Ni-MCM-41). Ni-MCM41 were prepared using hydrothermal method with variation of Ni content ratio (Si/Ni = 10, 20, and 40). This study consisted of several stages including; preparation of 0.24 M sodium 1-heptansulphonate, nickel sulphate 0.025 M, 0.05 M and 0.1 M and 1 M sodium silicate solutions. Synthesis of Ni-MCM-41 which was characterized using FTIR, XRD, DSC and BET. The adsorption process experiments included the preparation of mother liquor and methylene blue standard solution, preparation of standard solution and determination of maximum wavelength, preparation of test solution, contact time variation and concentration variation. Wavelength, contact time variation and concentration variation were determined using UV-Vis spectrophotometer. Analyze the adsorption process by determining the percentage and maximum capacity of adsorption. As well as determining the type of adsorption that occurs through Freundlich and Langmuir adsorption isotherms. FTIR results showed wave numbers between 3400-3200 cm-1 indicating the presence of Si-OH groups, C-H group stretching vibrations at 2925 cm-1, asymmetric stretching vibrations of Si-O at 1239 cm-1, Si-O-Ni bending vibrations at 557 cm-1 and symmetric and asymmetric Si-O-Si stretching vibrations at 1081 cm-1. XRD showed the characteristic structure of MCM-41 with higher crystallinity obtained at Ni-MCM-41 ratio (Si/Ni=40), DSC showed greater thermal resistance of Ni-MCM-41 ratio (Si/Ni=40) at 175.13 oC. The adsorption capacity of methylene blue dye by MCM-41 and Ni-MCM-41 ratio (Si/Ni=40) were 4.0322 mg/g and 4.2735 mg/g, respectively, following Langmuir adsorption isotherm.
Mesoporous Silica (MCM-48) as an Adsorbent for Methylene Blue Dye P. Taba; Nariskawati; A. H. Kasim; I W. Sutapa
International Journal of Acta Material Vol. 1 No. 2 (2025): February 2025
Publisher : Faculty Mathematics and Natural Sciences, Halu Oleo University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.62749/ijactmat.v1i2.14

Abstract

Research on the synthesis of mesoporous silica (MCM-48) has been conducted, with the material being utilized as an adsorbent for methylene blue (MB) dyes. The synthesis of MCM-48 was performed via a hydrothermal method, employing Ludox HS40 as the silica source and a mixture of CTAB and Triton X-100 as the templating agents. The surfactants were subsequently removed through washing with HCl-ethanol. Characterization of the synthesized material was achieved using techniques such as X-ray Diffraction (XRD), X-ray Fluorescence (XRF), Fourier Transform Infra-Red (FTIR) spectroscopy, and the Barrett-Joyner-Halenda (BJH) method. The MCM-48 materials utilized for MB adsorption included MCM-48 without prior washing (MCM-48-TC) and MCM-48 subjected to a single wash with HCl-ethanol (MCM-48-C1). Adsorption experiments for MB were conducted while varying the contact time to identify optimal conditions at neutral pH (6), and the adsorption capacity was assessed by performing adsorption at different concentrations under these optimal conditions. Isothermal adsorption was evaluated using the Langmuir and Freundlich isothermal models. The concentration of Methylene Blue post-adsorption was determined using a UV-Vis spectrophotometer at a wavelength of 660 nm. The results indicated that MCM-48 is an effective adsorbent for MB dye; the optimal adsorption time for MCM-48-TC was found to be 75 minutes, whereas for MCM-48-C1, it was 90 minutes. Adsorption by both MCM-48-TC and MCM-48-C1 conformed to the Freundlich isothermal model, with adsorption capacities of 1.4447 mg/g and 2.3900 mg/g, respectively.
Transesterification Reaction on Biodiesel Production from Bintaro Oil (Cerbera mangas L.) from Moluccas Island I W. Sutapa; A. Bandjar; H. Tehubijuluw; I. S. Ely; A. Kamari; C. Baskar; I N. Sudiana; L. O. Kadidae
International Journal of Acta Material Vol. 1 No. 2 (2025): February 2025
Publisher : Faculty Mathematics and Natural Sciences, Halu Oleo University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.62749/ijactmat.v1i2.15

Abstract

Research on the conversion of bintaro seed oil (Cerbera manghas L.) into biodiesel has been conducted utilizing a KOH catalyst. The biodiesel synthesis involved two reaction stages: esterification and transesterification. The esterification process was executed with a 1.25% H2SO4 (1 M) catalyst, utilizing a methanol-to-oil ratio of 1:9, at a temperature range of 60-65°C for a duration of 2 hours. Following the separation of methanol and triglycerides, transesterification proceeded with a methanol ratio of 1:12, which had previously reacted with KOH catalyst at varying weight percentages of 0.2%, 0.3%, 0.5%, 1%, and 1.5%. The transesterification reaction was conducted over a period of 2 hours at a temperature of 60-65°C. The optimal weight percentage of KOH catalyst identified for the transesterification reaction in the synthesis of biodiesel from bintaro seed oil was determined to be 0.3% KOH catalyst. The resultant biodiesel was subsequently characterized using Fourier Transform Infrared Spectroscopy (FT-IR) and Gas Chromatography-Mass Spectrometry (GC-MS). Physical property tests of the biodiesel fuel, conducted in accordance with ASTM methods, yielded a specific density of 0.8878 g/cm³, a kinematic viscosity of 6 mm²/s, a flash point of 132.5°C, and a pour point of 9°C.
Fabrication and Characterisation of Semi-Solid DSSCs Using Reduced Graphene Oxide (rGO) from Coal as a Filler in Polymer Gel Electrolytes W. O. Sukmawati; L. Ardan; I. Saleh; L. Agusu; I N. Sudiana; I. Usman
International Journal of Acta Material Vol. 2 No. 1 (2025): August 2025
Publisher : Faculty Mathematics and Natural Sciences, Halu Oleo University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.62749/ijactmat.v2i1.16

Abstract

In an effort to enhance the conductivity of TMSPMA-based polymer gel electrolytes (PGE), this study incorporated reduced graphene oxide (rGO) as a filler within the PGE matrix. The rGO was synthesized from sub-bituminous coal utilizing a modified Hummer method, while the PGE was formulated through a sol-gel process involving TMSPMA with varying proportions of rGO relative to the PGE. X-ray diffraction (XRD) measurements confirmed the presence of rGO, revealing a peak at a 2θ angle of 24.830° and a calculated crystalline size of 30.44 nm. Fourier-transform infrared spectroscopy (FTIR) characterization indicated that the identified functional groups were consistent with the molecular structure of TMSPMA. Impedance measurements conducted using an LCR meter demonstrated that the incorporation of rGO up to 0.04 g significantly enhanced the conductivity, achieving a value of 0.013 S/cm. Furthermore, photovoltaic performance testing of dye-sensitized solar cells (DSSC) indicated that the highest efficiency of 1.03% was attained with the PGE containing 0.04 g of rGO.
The Latest Green Synthesis of Silver Nanoparticles Using Cocoa Fruit Peel Extract (Theobroma cacao L.) as a Bioreductant S. Kasim; W. Riskiyani; A.N. Zahra; I W. Sutapa; A. Kamari; C. Baskar
International Journal of Acta Material Vol. 2 No. 1 (2025): August 2025
Publisher : Faculty Mathematics and Natural Sciences, Halu Oleo University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.62749/ijactmat.v2i1.17

Abstract

Cocoa fruit peel contains a variety of phytochemicals, including tannins, flavonoids, alkaloids, terpenoids, and saponins, which are anticipated to act as reducing agents. The green synthesis method employs methanol as a solvent to extract organic compounds from cocoa fruit peel, which serve as bio-reductants. This study aims to synthesize silver nanoparticles utilizing cocoa fruit peel extract as a bio-reductant. It involved the preparation of silver nitrate (AgNO₃) solutions at varying concentrations of 0.5 mM, 1 mM, and 1.5 mM. Characterization of the nanoparticles was conducted using a UV-Vis spectrophotometer and a Particle Size Analyzer (PSA). The study observed the formation of silver nanoparticle colloids after 30 minutes of stirring, as evidenced by a color change in the colloid to brown. UV-Vis spectrophotometer analysis revealed a maximum wavelength of 461 nm with an absorbance value of 2.032. Notably, as the concentration of silver nitrate (AgNO₃) increased, the absorbance value correspondingly increased. The PSA results indicated that the silver nanoparticles had an average size of 96.08 nm.
Unveiling Non-Covalent Molecular Interactions: A Comprehensive Review Integrating DFT and Crystallographic Insights W. O. N. Haryanti; I W. Sutapa; Sahidin; L. Ahmad; L. O. A. N. Ramadhan
International Journal of Acta Material Vol. 2 No. 1 (2025): August 2025
Publisher : Faculty Mathematics and Natural Sciences, Halu Oleo University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.62749/ijactmat.v2i1.18

Abstract

Non-covalent interactions (NCIs) are crucial in elucidating molecular recognition, supramolecular architecture, and material properties. This review synthesizes findings from 20 recent studies (2013–2025), with a focus on key interaction types: hydrogen bonding, π–π stacking, Van der Waals forces, and less prevalent modes such as chalcogen bonding and excited-state interactions. Computational methodologies, particularly dispersion-corrected density functional theory (DFT), benchmark datasets (e.g., S22, HB300SPX), and emerging machine learning (ML) corrections, have markedly enhanced the accuracy of NCI modeling. Experimental techniques, including X-ray diffraction and infrared/Raman spectroscopy, continue to substantiate theoretical predictions. Hydrogen bonds are predominant in influencing structural stability and crystal packing, while π–π interactions play a vital role in stabilizing aromatic systems. Van der Waals interactions are particularly significant in layered materials and adsorption phenomena. Recent advancements, such as neural network potentials (NNPs) and non-empirical functionals (e.g., r²SCAN+MBD@HF), provide accurate predictions even in complex environments. This review underscores the interplay between theoretical and experimental approaches and highlights prospective directions in modeling weak interactions across a range of chemical systems.
Optimisation of Asphalt Extraction from Asbuton Using Microwave-Assisted Extraction (MAE) Method Hikmayani; I W. Sutapa; Sahidin; L. O. Ahmad
International Journal of Acta Material Vol. 2 No. 1 (2025): August 2025
Publisher : Faculty Mathematics and Natural Sciences, Halu Oleo University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.62749/ijactmat.v2i1.19

Abstract

Buton natural asphalt (Asbuton) is a strategic non petroleum bitumen resource with promising potential in road construction. However, conventional extraction methods such as Soxhlet and reflux suffer from long processing times, high energy demand, and excessive solvent use. This review evaluates Microwave-Assisted Extraction (MAE) as a green and efficient alternative for extracting bitumen from Asbuton. MAE employs rapid dielectric heating, enabling selective bitumen release while minimizing solvent consumption. Key process variables, including solvent polarity, solid-to-solvent ratio, temperature, extraction time, microwave power, and system pressure are critically reviewed. Comparative data show that MAE significantly improves extraction yield and operational efficiency. In addition, Response Surface Methodology (RSM) is discussed as a modeling tool to optimize variable interactions and identify ideal extraction conditions. Visual aids such as flow diagrams and comparative tables are used to clarify performance metrics and technical constraints. The review also outlines major challenges in MAE implementation, including microwave penetration in low-dielectric matrices and the need for scalable reactor designs. Overall, this paper provides a comprehensive perspective on MAE-based extraction for Asbuton, offering insight into its advantages, limitations, and directions for future research and industrial application.
Development of Eco-friendly Antimicrobial Bricks Using Nickel Slag Waste Enriched with TiO2 to Counteract E. coli Contamination L. Agusu; W. O. Nurtia; M. Z. Muzakkar; I W. Sutapa; Y. Ishikawa; Y. Fujii; T. Asano; S. Mitsudo; Y. Tatematsu
International Journal of Acta Material Vol. 2 No. 1 (2025): August 2025
Publisher : Faculty Mathematics and Natural Sciences, Halu Oleo University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.62749/ijactmat.v2i1.20

Abstract

This study investigates the use of nickel slag waste, enriched with TiO2, as a sustainable material for producing antimicrobial bricks. The research focuses on evaluating the impact of variations in firing time and the addition of nickel slag on the mechanical properties of the bricks, as well as their antibacterial effectiveness against E. coli bacteria. The bricks were produced using an electric furnace with different composition ratios of clay, nickel slag, and TiO2. Results demonstrate that the optimal compressive strength of the bricks is 21.673 × 10⁵ N/m², achieved with a clay:slag:TiO2 ratio of 90:5:5 at a firing temperature of 1000°C for 12 hours. The water absorption rate for this composition was found to be 16.98%. Antimicrobial tests, using the scatter method, revealed that TiO2-enriched bricks significantly inhibited E. coli growth, with only two colonies present compared to 77 colonies on bricks without TiO2. X-ray diffraction (XRD) analysis confirmed the presence of key oxides such as SiO2, TiO2, and CaCO3. These findings suggest that nickel slag, when combined with TiO2, can be an effective additive in clay-based bricks to inhibit E. coli growth, offering potential for applications in water purification and environmental sustainability. Furthermore, the use of advanced heating techniques such as microwaves or gyrotrons may enhance the bricks’ structural integrity and antimicrobial performance in future applications.
Application of Rice Husk Silica Ash Activated using NH4OH to Reduce Calcium Ion (Ca2+) Levels in Brackish Water L. Harimu; Mutmainnah; Dahlan; W. O. Mulyana; E. C. Mandasar; I W. Sutapa; A. Kamari
International Journal of Acta Material Vol. 2 No. 1 (2025): August 2025
Publisher : Faculty Mathematics and Natural Sciences, Halu Oleo University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.62749/ijactmat.v2i1.21

Abstract

A study was conducted to investigate the efficacy of NH4OH-activated rice husk ash silica in mitigating calcium ion (Ca²⁺) concentrations in brackish water. The primary objective of this research was to evaluate the adsorption capacity of NH4OH-activated rice husk ash silica for Ca²⁺ ions dissolved in brackish water. The experimental methodology employed various adsorption parameters, including pH levels (5, 6, 7, 7.5, 8, 9), adsorbent masses (0.01, 0.025, 0.05, 0.1, 0.2 g), contact times (15, 30, 45, 60, 75 minutes), and concentration levels (25, 50, 75, 100 ppm) for Ca²⁺ ions. The findings indicated that optimal adsorption occurred at an adsorbent mass of 0.025 grams, a pH of 7.5, a contact time of 30 minutes, and a concentration of 50 ppm, resulting in an adsorption capacity of 67.2 mg/g. Furthermore, under optimal conditions, the application of activated rice husk ash silica as an adsorbent in brackish water demonstrated an NH4OH adsorption capacity of 40 mg/g, with a brackish water concentration of 40 mg/g. Therefore, it can be concluded that NH4OH-activated rice husk ash silica is a viable adsorbent for reducing calcium ion (Ca²⁺) levels in brackish water.

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