Prof. Charitha Jayaruk Thambiliyagodage

Person:
Prof. Charitha Jayaruk Thambiliyagodage

ORCID

https://orcid.org/0000-0003-0906-4441

Google Scholar

https://scholar.google.com/citations?user=kdc5vsQAAAAJ

Name

Prof. Charitha Jayaruk Thambiliyagodage

Biography

Jayaruk is a graduate of the University of Colombo. He pursued his PhD in Chemistry from The University of Alabama, USA. He has specialized in Materials, Analytical and Physical Chemistry. Currently, he is working as an Assistant Professor at the Department of Applied Sciences, SLIIT. He is the coordinator of the BSc Biotechnology degree programme. He has been awarded the chartered chemist designation by the Institute of Chemistry, Ceylon. He supervises Postgraduate students at the University of Colombo and the University of Kelaniya and supervises undergraduate students at the Institute of Chemistry. He is interested in doing research on using nanomaterials in water purification and as antimicrobial reagents. Further, he is interested in researching on algae and plant materials for their pharmaceutical and cosmeceutical activities. He has specialized in many instruments like Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM), X-Ray Diffractometer (XRD), X-Ray Photoelectron Spectrometer (XPS), Gas chromatograph-Mass spectrometer (GC-MS), Raman Spectrometer, FT-IR spectrometer, UV-Visible Spectrophotometer, Brunauer-Emmett-Teller (BET) surface area analyzer etc. He is interested in practical-based science education and believes in uplifting the research culture among upcoming scientists in the country.

Research Interests

Application of nanomaterials for water purification Novel nanomaterials incorporated cosmeceuticals and pharmaceuticals Natural material based neutraceuticals Alternative energy sources Novel packaging materials Environmental Chemistry

Organizational Units

Organizational Unit

Faculty of Humanities & Sciences

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Now showing 1 - 10 of 20

Open Access
Influence of Laboratory Synthesized Graphene Oxide on the Morphology and Properties of Cement Mortar
(MDPI, 2023-01) Ganesh, S; Thambiliyagodage, C; Perera, S. V. T. J; Rajapakse, R.K.N.D
The introduction of Graphene Oxide (GO), a nanomaterial, has shown considerable promise in improving the mechanical properties of cement composites. However, the reasons for this improvement are not yet fully understood and demand further research. This study aims to understand the effect of laboratory-produced GO, using Tour’s method, on the mechanical properties and morphology of cement mortar containing GO. The GO was characterized using Fourier-transform infrared spectroscopy, X-ray Photoelectron Spectroscopy (XRD), X-ray powder diffraction, and Raman spectroscopy alongside Scanning electron microscopy (SEM). This study adopted a cement mortar with GO percentages of 0.02, 0.025, 0.03, 0.035, and 0.04 with respect to the weight of the cement. The presence of GO in cement mortar increased the density and decreased the consistency and setting times. At the optimum of 0.03% GO viscous suspension, the mechanical properties such as the 28-day compressive strength, splitting tensile strength, and flexural strength were enhanced by 41%, 83%, and 43%, respectively. In addition, Brunauer–Emmett–Teller analysis indicates an increase in surface area and volume of micropores of GO cement mortar, resulting in a decreased volume of mesopores. The improvement in properties was due to increased nucleation sites, calcium silicate hydrate (CSH) density, and a decreased volume of mesopores.
Open Access
Fabrication of r-GO/GO/α-Fe2O3/Fe2TiO5 Nanocomposite Using Natural Ilmenite and Graphite for Efficient Photocatalysis in Visible Light
(MDPI, 2023-01) Usgodaarachchi, L; Jayanetti, M; Thambiliyagodage, C; Liyanaarachchi, H; Vigneswaran, S
Hematite (α-Fe2O3) and pseudobrookite (Fe2TiO5) suffer from poor charge transport and a high recombination effect under visible light irradiation. This study investigates the design and production of a 2D graphene-like r-GO/GO coupled α-Fe2O3/Fe2TiO5 heterojunction composite with better charge separation. It uses a simple sonochemical and hydrothermal approach followed by L-ascorbic acid chemical reduction pathway. The advantageous band offset of the α-Fe2O3/Fe2TiO5 (TF) nanocomposite between α-Fe2O3 and Fe2TiO5 forms a Type-II heterojunction at the Fe2O3/Fe2TiO5 interface, which efficiently promotes electron-hole separation. Importantly, very corrosive acid leachate resulting from the hydrochloric acid leaching of ilmenite sand, was successfully exploited to fabricate α-Fe2O3/Fe2TiO5 heterojunction. In this paper, a straightforward synthesis strategy was employed to create 2D graphene-like reduced graphene oxide (r-GO) from Ceylon graphite. The two-step process comprises oxidation of graphite to graphene oxide (GO) using the improved Hummer’s method, followed by controlled reduction of GO to r-GO using L-ascorbic acid. Before the reduction of GO to the r-GO, the surface of TF heterojunction was coupled with GO and was allowed for the controlled L-ascorbic acid reduction to yield r-GO/GO/α-Fe2O3/Fe2TiO5 nanocomposite. Under visible light illumination, the photocatalytic performance of the 30% GO/TF loaded composite material greatly improved (1240 Wcm−2). Field emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy (HR-TEM) examined the morphological characteristics of fabricated composites. X-ray photoelectron spectroscopy (XPS), Raman, X-ray diffraction (XRD), X-ray fluorescence (XRF), and diffuse reflectance spectroscopy (DRS) served to analyze the structural features of the produced composites. © 2022 by the authors.
Open Access
Fabrication of dual Z-scheme g-C3N4/Fe2TiO5/Fe2O3 ternary nanocomposite using natural ilmenite for efficient photocatalysis and photosterilization under visible light
(Elsevier, 2022-11-11) Thambiliyagodage, C; Liyanaarachchi, H; Kumar, A; Jayanetti, M; Usgodaarachchi, L; Lansakara, B
The advanced oxidation process is a prominent method available to remove dyes released to normal water reservoirs to alleviate water scarcity. We report the fabrication of novel g-C3N4/Fe2TiO5/Fe2O3 using natural ilmenite sand as the precursor of the metallic semi-conductors exploration of a heterostructure for photodegradation of methylene blue under sunlight. Ternary composites were synthesized by varying g-C3N4 with respect to Fe2TiO5/Fe2O3 and varying Fe2TiO5/Fe2O3 with respect to g-C3N4 where the varying component was varied as 8, 24 and 40%, respect to the constant material. The hybridization of the three semi-conductors has been confirmed by the microscopic, chemical, and structural analyses. X-ray diffraction patterns show the presence of all three g-C3N4, Fe2TiO5 and α-Fe2O3 while the transmission electronic microscopic and scanning electronic microscopic images show the heterogeneous distribution of the metal oxide nanoparticles on g-C3N4 matrix forming the composite. HRTEM images further reveal the junction of Fe2TiO5 and α-Fe2O3. X-ray photoelectron spectra show the existence of s-triazine and heptazine rings in the composites with Fe3+ and Ti4+ as the only oxidation states of Fe and Ti. Fe2TiO5/Fe2O3/40% g-C3N4 with bandgap of 2.63 eV calculated by diffuse reflectance UV-Visible spectroscopy showed the highest photocatalytic activity (0.009 min−1) being 1.3 times greater than the Fe2TiO5/Fe2O3 nanoparticles. Enhanced photocatalytic activity over the fabricated composites was observed due to the increased visible light absorption, efficient charge separation and improved charge transportation. g-C3N4 coupled with 40% Fe2TiO5/Fe2O3 showed the highest antibacterial activity against gram-negative E.Coli. The synthesis of dual Z-scheme g-C3N4/Fe2TiO5/Fe2O3 ternary composite provides new sights in developing novel photocatalysts using natural ilmenite sand for environmental applications.
Open Access
Kinetics and Thermodynamics Study of Methylene Blue Adsorption to Sucrose- and Urea-Derived Nitrogen-Enriched, Hierarchically Porous Carbon Activated by KOH and H3PO4
(American Chemical Society, 2023-04-27) Liyanaarachchi, H; Thambiliyagodage, C; Lokuge, H; Vigneswaran, S
Hierarchically porous nitrogen-enriched carbon materials synthesized by polymerization of sucrose and urea (SU) were activated by KOH and H3PO4 (SU-KOH and SU-H3PO4, respectively). Characterization was undertaken and the synthesized materials were tested for their ability to adsorb methylene blue (MB). Scanning electron microscopic images along with the Brunauer−Emmett−Teller (BET) surface area analysis revealed the presence of a hierarchically porous system. X-ray photoelectron spectroscopy (XPS) confirms the surface oxidation of SU upon activation with KOH and H3PO4. The best conditions for removing dyes utilizing both activated adsorbents were determined by varying the pH, contact time, adsorbent dosage, and dye concentration. Adsorption kinetics were evaluated, and the adsorption of MB followed second-order kinetics, suggesting the chemisorption of MB to both SU-KOH and SUH3PO4. Times taken to reach the equilibrium by SU-KOH and SU-H3PO4 were 180 and 30 min, respectively. The adsorption isotherm data were fitted to the Langmuir, Freundlich, Temkin, and Dubinin models. Data were best described by the Temkin isotherm model for SU-KOH and the Freundlich isotherm model for SU-H3PO4. Thermodynamics of the adsorption of MB to the adsorbent was determined by varying the temperature in the range of 25−55 °C. Adsorption of MB increased with increasing temperature, suggesting that the adsorption process is endothermic. The highest adsorption capacities of SU-KOH and SU-H3PO4 (1268 and 897 mg g−1 , respectively) were obtained at 55 °C. Synthesized adsorbents were effective in removing MB for five cycles with some loss in activity. The results of this study show that SU activated by KOH and H3PO4 are environmentally benign, favorable, and effective adsorbents for MB adsorption.
Open Access
Antibacterial Activity of Zn Decorated TiO2 Nanocomposites
(Faculty of Humanities and Sciences, SLIIT, 2023-11-01) Kumarasinghe, N.M.A,; Thambiliyagodage, C; Jayanetti, M; Liyanaarachchi, H
Bacterial infections have a significant public health impact. Infections are caused by bacteria in animals, plants as well as humans. Pathogenic bacteria can produce toxins, which are chemical poisons that interfere with cell function such as digestion of normal human enzymes, evasion of infection-fighting white blood cells, and immune clearance. Antibiotic prophylaxis is used to prevent bacterial infection. Antibiotic resistance is one of the most serious concerns in world health. Antibacterial nanoparticles are one possible answer to antimicrobial resistance. These nanomaterials not only kill antibiotic-resistant bacteria through various modes of action but, they can also be employed in conjunction with existing clinically relevant antibiotics to help overcome antimicrobial resistance mechanisms. In this study, anodized titanium dioxide (TiO2) nanorods were treated hydrothermally with zinc oxide (ZnO) nanoparticles to give titanium (Ti) antibacterial properties. The antibacterial activity of synthesized samples was investigated by Agar Well Diffusion method at 40 mg/ml concentration, against gram negative Klebsiella pneumoniae. To determine the antibacterial activity, the diameter of the zone of inhibition was measured, and the resulting data were statistically analyzed. Zn/TiO2 nano particles were characterized by using X-ray diffraction (XRD) Analysis.
Embargo
Synthesis of Amine Functionalized Silica- Cu4O3 Adsorbent from Rice Husk for Efficient Removal of Crystal Violet from Aqueous Solution
(Faculty of Humanities and Sciences,SLIIT, 2021-09-25) Usgodaarachchi, L.; Thambiliyagodage, C; Angappan, S
Silica based Nano adsorbent (SCN) synthesized using rice husk as the raw material via sol- gel pathway. Silica nanoparticles were successfully functionalized with 3-aminopropyl triethoxysilane (APTES) via in-situ functionalization method. Synthesized nanoparticles were characterized by XRD and FT-IR. The equilibrium adsorption capacity of 0.02g of SCN to adsorb 10 mg/L crystal violet (CV) was 20.09 mg/g. The influence of pH, adsorbent dosage, and initial CV concentration on adsorption of CV to SCN were studied. The equilibrium data for CV adsorption on SCN well fitted to Freundlich model, with a Freundlich adsorption capacity of 8.23 mg g-1. The adsorption of CV could be best described by the pseudosecond order model with 0.99 linier regression coefficient.
Embargo
Assessing the Efficacy of Machine Learning Algorithms in Predicting Critical Properties of Gold Nanoparticles for Pharmaceutical Applications
(Springer Nature Link, 2025-07-08) Fernando, H; Mohottala, S; Jayanetti, M; Thambiliyagodage, C
Au nanoparticles are increasingly used in pharmaceuticals, but their synthesis is costly and time-intensive. Machine Learning can help optimize this process. In this research, eight distinct Machine Learning models were implemented and optimized on a dataset comprising 3000 records of gold nanoparticles. The performance of these models was assessed using four accuracy metrics and the time required for training and inference. The results are promising, with all seven models demonstrating high accuracy and low time requirements. Notably, the XGBoost and Artificial Neural Network models exhibited exceptional performance, with Mean Squared Error values of 0.0235 and 0.0098, Mean Absolute Error values of 0.1021 and 0.0674, Mean Absolute Percentage Deviation values of 0.4945 and 0.3590, R2 scores of 0.9995 and 0.9998, and inference times of 0.0029 and 0.4299 s, respectively. The Explainable Artificial Intelligence analysis of the resulting models revealed some interesting insights into how the models make the predictions and what factors heavily contribute to the nanoparticle AVG_R, allowing chemists to optimize the synthesis for gold nanoparticles better. The key contributions of the research include the design and development of eight Machine Learning models using industry-standard frameworks, the training, tuning, and evaluation of these eight models using five different metrics, and further assessment of these trained models using Explainable Artificial Intelligence. The findings indicate a substantial potential for applying neural networks in the design phase of nanoparticle synthesis, which could lead to significant reductions in both the time and cost required for synthesizing Au nanoparticles for pharmaceutical applications.
Embargo
Effect of Co-pollutants on the Photocatalytic Activity of Fe doped ZnO Nanoparticles on the Degradation of Methylene Blue
(IEEE, 2022-07-18) Thambiliyagodage, C; Lokuge, N
ZnO nanoparticles and Fe doped ZnO nanoparticles with varying Fe concentrations as 0.025, 0.05, 0.075, and 0.1% respective to Zn, was successfully synthesized by the sol-gel method. Synthesized nanoparticles were characterized by X-ray diffractometry (XRD) and Raman spectroscopy. As revealed by both studies Fe has successfully doped to ZnO without causing any lattice distortions. Synthesized catalysts were photocatalytically active in degrading methylene blue under sunlight. The effect of co-pollutants; Rhodamine B, Pb 2+ , PO43− and S2O32− on the rate of photodegradation was studied and it was found that Rhodamine B, Pb 2+ , and PO43− reduce the rate and S2O32− increases the rate of photodegradation.
Open Access
Recent Advances in Chitosan-Based Applications—A Review
(MDPI, 2023-03-03) Thambiliyagodage, C; Jayanetti, M; Mendis, A; Ekanayake, G; Liyanaarachchi, H; Liyanaarachchi, S
Chitosan derived from chitin has gathered much interest as a biopolymer due to its known and possible broad applications. Chitin is a nitrogen-enriched polymer abundantly present in the exoskeletons of arthropods, cell walls of fungi, green algae, and microorganisms, radulae and beaks of molluscs and cephalopods, etc. Chitosan is a promising candidate for a wide variety of applications due to its macromolecular structure and its unique biological and physiological properties, including solubility, biocompatibility, biodegradability, and reactivity. Chitosan and its derivatives have been known to be applicable in medicine, pharmaceuticals, food, cosmetics, agriculture, the textile and paper industries, the energy industry, and industrial sustainability. More specifically, their use in drug delivery, dentistry, ophthalmology, wound dressing, cell encapsulation, bioimaging, tissue engineering, food packaging, gelling and coating, food additives and preservatives, active biopolymeric nanofilms, nutraceuticals, skin and hair care, preventing abiotic stress in flora, increasing water availability in plants, controlled release fertilizers, dye-sensitised solar cells, wastewater and sludge treatment, and metal extraction. The merits and demerits associated with the use of chitosan derivatives in the above applications are elucidated, and finally, the key challenges and future perspectives are discussed in detail.
Open Access
Efficient photocatalysis of carbon coupled TiO2 to degrade pollutants in wastewater – A review
(Elsevier, 2022-08-27) Thambiliyagodage, C
Water pollution caused by human activities is a monumental problem that the world is facing today. The use of polluted water for domestic, industrial, and agricultural applications creates severe hazardous issues. Therefore, decontamination of polluted water is greatly important. The advanced oxidation process is preferred to purify contaminated water as the pollutants are completely degraded to harmless products. TiO2 is the most widely researched photocatalyst due to its chemical stability, low cost and eco-friendliness. However, the use of TiO2 is limited as it is only sensitive to UV range due to its high band gap (3.0 eV for rutile) and the possible electron-hole pair recombination. TiO2 has been coupled with carbon-based materials to enhance photocatalytic activity by enhancing charge separation and visible light absorption. This review summarizes the recent use of TiO2 coupled to activated carbon, carbon nanotubes, graphene derivatives, and g-C3N4 to degrade different pollutants found in water including dyes, pesticides, pharmaceuticals, phenols and heavy metals. The advantages and disadvantages of using each carbon-based material are discussed. Further, the challenges and opportunities associated with all the materials are presented. Finally, recommendations and possible future outlooks are briefed in this review.