Faculty of Humanities and Sciences-Scopus2

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Development of the major triterpenoids and oil in the fruit and seeds of neem (Azadirachta indica)
(No longer published by Elsevier, 1996-09-01) JOHNSON, S; MORGAN, D. E; PEIRIS, C. N
In order to learn the best time for harvesting Neem (Azadirachta indica) seeds, the amount of the five major triterpenoids, together with the oil content have been determined throughout a fruiting season in six selected trees in Sri Lanka. The triterpenoid content and the relative proportions of the major compounds changed little from the hard green fruit stage to mature seeds, while the oil content increased markedly with time. The highest content of azadirachtin (10 mg g-1seed kernels) was recorded in newly ripened seeds. There was some loss of salannin and azadirachtin in storage after harvesting for up to 6 months.
Open Access
Gamma-hydroxybutyrate accumulates in green tea and soybean sprouts in response to oxygen deficiency
(Canadian Science Publisher, 2003-10) Shelp, B. J; Allan, W. L; Peiris, C; Bown, A. W
Gamma-hydroxybutyrate (GHB) is an illicit drug, which may be derived in plants from a stress-inducible metabolite known as gamma-aminobutyrate. Here, oxygen deficiency caused the accumulation of GHB in green tea and soybean sprouts (76 and 155 nmol g-1 fresh weight, respectively). These findings demonstrate that GHB levels are elevated in severely modified atmospheres, but they pose no risk to human health. Further work is required to assess the extent of this phenomenon.
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Catalytic graphitization in nanocast carbon monoliths by iron, cobalt and nickel nanoparticles
(Pergamon, 2018-08-01) Thambiliyagodage, C. J; Ulrich, S; Araujo, P. T; Bakker, M. G
Hierarchically porous carbon monoliths containing metal (Fe, Co, Ni) nanoparticles were synthesized in a one-pot synthesis through a nanocasting technique using silica (SiO2) as the template. The macropore structure of SiO2 has been replicated in nanocast carbon and N2 adsorption analysis shows that the monoliths have high surface area, high mesopore volume, and that micropores are also present. The temperature effect on catalytic graphitization was studied by using x-ray diffraction (XRD), transmission electron microscope (TEM) and Raman spectroscopy. It is observed that iron was capable of producing turbostratic carbon at 500 °C, while turbostratic carbon was produced at temperatures of 700 °C when cobalt and nickel are present. Iron, cobalt, and nickel were found to be good graphitization catalysts with the order of catalytic activity being iron > cobalt > nickel. Raman spectroscopy experiments provide insight into the degree of ordering of the carbon of each sample and are in agreement with the results from the other techniques: with increasing pyrolysis temperature, with and without the presence of metals, ordering of amorphous carbon is confirmed. Detailed analysis of the Raman spectroscopic data showed clear differences between the metal catalyzed and non-catalyzed samples enabling the contributions from the two different mechanisms to be clearly distinguished.
Open Access
Detecting a decline in serial homicide: Have we banished the devil from the details?
(Cogent, 2019-01-01) Yaksic, E; Allely, C; De Silva, R; Smith-Inglis, M; Konikoff, D; Konikoff, K; Gordon, D; Denisov, E; Keatley, D. A
The current research provides perspective regarding the true prevalence of serial murderers in modern society and addresses the conflict between the evidenced decline in serial homicide and the viewpoint that the phenomenon is increasing. The likelihood that serial murderers are responsible for most unresolved homicides and missing persons is examined in the context of a declining prevalence. A mixed methods approach was used, consisting of a review of a sample of unresolved homicides, a comparative analysis of the frequency of known serial homicide series and unresolved serial homicide series, and semi-structured interviews of experts. In failing to become serial killers, aspiring and probable serial killers and spree killers have impacted the rate of serial murder by not reaching their potential. The past decade contained almost half the cases (13%) that existed at the 1980s peak of serial homicide (27%). Only 282 (1.3%) strangled females made up the 22,444 unresolved homicides reviewed. Most expert respondents thought it unreasonable that any meaningful proportion of missing persons cases are victims of serial homicide. Technology, shifts in offending behavior, proactive law enforcement action, and vigilance of society have transformed serial killing and aids in viewing offenders as people impacted by societal shifts and cultural norms. The absence of narrative details inhibited some aspects of the review. An exhaustive list
Open Access
Effect of surfactants on morphology and textural parameters of silica nanoparticles derived from paddy husk and their efficient removal of methylene blue
(International Conference on Innovations in Energy Engineering & Cleaner Production (IEE CP’21), 2021) Gunathilaka, H; Thambiliyagodage, C. J; Usgodaarchchi, L; Angappan, S
Effective removal of textile dyes is important in environmental remediation especially for decontamination of wastewater. Herein, we report the synthesis of mesoporous silica nanoparticles (MSNs) from paddy husk with varying concentrations of surfactants, Cetyltrimethylammonium bromide (CTAB), and Polyethyleneglycol (PEG) by sol-gel synthesis method. Ratios of the surfactants CTAB: PEG were varied as 2:0 (MSN1),1:1 (MSN2), 0:2 (MSN3). MSNs were characterized by scanning electron microscope (SEM), Brunauer-Emmett-Teller surface area analyzer (BET), Thermogravimetric analyzer (TGA), and X-ray diffractometer. According to the SEM images, MSNs of all the combinations were aggregated with spherical and irregular shaped nanoparticles. MSNs synthesized with a 1:1 surfactant ratio showed more spherical nanoparticles. BET surface areas of MSN1, MSN2, and MSN3 are 468.35, 95.94, 177.46 m2/g, respectively. TGA curve indicated that desorption of the physisorbed water was completed at 125 °C. The effect of dye removal by the MSNs was studied on the adsorption of methylene blue (MB). Effect of dye concentration (5-30 mg/l), adsorbent dosage (5-20 mg), pH of the medium (2-10), ionic strength of the medium (0-6g/l NaCl), presence of a heavy metal (Pb2+- 0-500 mg/l) and temperature (25-55 °C) on MB adsorption was studied. At all the varied parameters, the adsorption efficiency of MB varied as MSN1> MSN3> MSN2, being similar to the trend of the surface area. The percentage of MB adsorption decreased with increasing MB concentration while it increased with increasing adsorbent dosage. The highest efficiency of MB adsorption was obtained at pH 10 and it decreased with increasing ionic strength and increasing concentration of heavy metal ions. The maximum percentage of MB adsorption resulted at 55 °C. Therefore, it can be concluded that the MSNs synthesized using only CTAB as the surfactant is an effective adsorbent in removing textile dyes from wastewater.
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Fabrication of Fe2TiO5/TiO2 binary nanocomposite from natural ilmenite and their photocatalytic activity under solar energy
(Elsevier, 2021-01-01) Thambiliyagodage, C. J; Mirihana, S; Wijesekera, R; Madusanka, D. S; Kandanapitiye, M; Bakker, M
Heterogeneous photocatalysis is an attractive alternative route to enhance the degradation of environmental pollutants. In this work, we have fabricated Fe2TiO5/TiO2 binary nanocomposites using natural ilmenite via bottom up approach. Synthesized nanocomposites were characterized by X-ray diffractometry, X-ray fluorescence, transmission electron microscopy, Raman spectroscopy, diffuse reflectance UV–Visible spectroscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy. These nanoparticles are in the range of 40–70 nm and are of type I heterostructure with a band gap of 2.02 eV. They are sensitive to visible light and show higher photocatalytic activity under direct solar energy. Photocatalytic activity of Fe2TiO5/TiO2 was assessed using a model textile dye, methylene blue. Over a period of 2 h, 76% of methylene blue was photodegraded at a rate of 0.0084 min−1 in the presence of Fe2TiO5/TiO2.
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Photocatalytic activity of N, Fe and Cu co-doped TiO2 nanoparticles under sunlight
(Elsevier, 2021-01-01) Thambiliyagodage, C. J; Usgodaarachchi, L
Photocatalytic activity of N doped with one transition metal is well known. This article reports the synthesis of TiO2 nanoparticles doped with only N, N co-doped with Fe, N co-doped with Cu and N co-doped with both Fe and Cu by sol-gel method. Their photocatalytic activity was evaluated for the degradation of methylene blue under sunlight. Nanoparticles were characterized by X-ray diffractometry (XRD), Raman spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and diffuse reflectance UV–visible spectroscopy (DRS). XRD analysis revealed the presence of anatase phase TiO2 nanoparticles which was confirmed by Raman spectroscopic and TEM analysis. The crystal structure has not been disturbed by doping with N, Fe and Cu as shown by both XRD and Raman analysis. TEM and SEM images exhibit the nanoparticles which are interconnected due to sintering. XPS analysis revealed the presence of the only Ti4+ in undoped TiO2 but both Ti4+ and Ti3+ are present in doped TiO2 nanoparticles. According to the DRS analysis, the band gap of all doped TiO2 is lower than that of the undoped TiO2, where N, Fe and Cu co-doped TiO2 showed the lowest band gap (2.51 eV) proving that the visible light sensitivity of TiO2 increase with metal and non-metal doping. The rate of photodegradation of methylene blue in the presence of undoped TiO2 (0.016 min−1) is higher than all the doped TiO2 nanoparticles. N doped TiO2 show the highest activity among the doped TiO2 nanoparticles (0.006 min−1). Doped TiO2 nanoparticles showed a lower photocatalytic activity due to the electron hole pair recombination and the shielding effect of the dopants.
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How much damage do serial homicide offenders wrought while the innocent rot in prison? A tabulation of preventable deaths as outcomes of sentinel events
(Routledge, 2021-01-02) Yaksic, E; Allred, T. B; Drakulic, C; Mooney, R; De Silva, R; Geyer, P; Wills, A; Comerford, C; Ranger, R
The criminal justice system has allowed serial homicide offenders (SHOs) to commit additional homicides by failing to identify them after their initial homicide. Recidivism has been possible in instances where the SHO benefited from the wrongful incarceration of an innocent person for one of their homicides. Data from the National Registry of Exonerations was utilized to tabulate the full extent of these sentinel events, defined as the number of deaths that could have been prevented. Additional research was conducted to identify where victims fell in the offender’s killing sequence. This ancillary data revealed the number of victims whose deaths could have been prevented had the offender been apprehended earlier in their series of homicides. Sixty-two SHOs were responsible for 249 deaths, 114 of which were committed after an innocent person was incarcerated for the SHO’s initial homicide. To prevent further loss of life, law enforcement must: act upon accurate information; lower the SHO evidentiary threshold; prevent personal bias from influencing investigative steps; obtain training in the behavior of SHOs; admit mistakes; and re-examine convictions if wrongdoing is suspected.
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A heuristic study of the similarities and differences in offender characteristics across potential and successful serial sexual homicide offenders
(researchgate.net, 2021-08) Yaksic, E; Harrison, M; Konikoff, D; Mooney, R; Allely, C; De Silva, R; Matykiewicz, B; Inglis, M; Giannangelo, S. J; Daniels, S; Sarteschi, C. M
This heuristic study examined potential serial sexual homicide offenders (SSHOs), an unacknowledged offender group comprised of aspiring and probable SSHOs, and compared them with successful SSHOs. Data were collected on six aspiring SSHOs who each failed a single homicide attempt, 16 probable SSHOs who committed 17 homicides in separate events, and 13 successful SSHOs who killed 90 victims in separate events. The study results indicate that while potential SSHOs share more in common with successful SSHOs than they do with single-victim nonsexual homicide offenders, and that there is an overlap between potential SSHOs and successful SSHOs, there is currently insufficient evidence to suggest that there are discreet transitions among categories. While few potential SSHOs strive to become successful SSHOs, this may be due to weak or nonexistent emotional triggers. Being a potential SSHO does not appear to be a predictable first step on a pathway towards becoming a successful SSHO, as potential SSHOs cannot reliably be thought of as prospective SSHOs if all things were equal. The present study could not foresee all potential SSHOs becoming successful ones. An as yet unidentified number of factors still appear to separate potential SSHOs from successful SSHOs.
Open Access
Photocatalytic activity of Go/Fe3O4 fabricated by Sri Lankan graphite under visible light irradiation
(Faculty of Science, University of Kelaniya, Sri Lanka, 2021-10) Usgodaarachchi, L; Thambiliyagodage, C. J
Graphene oxide (GO) was synthesized using Sri Lankan naturally available graphite by modified Hummer’s method. Fe3O4 nanoparticles were synthesized successfully by co-precipitation of Fe3+ and Fe2+ in a 2:1 molar ratio via the addition of NH4OH. Magnetically separable GO/Fe3O4 nanocomposite was fabricated by synthesizing Fe3O4 nanoparticles in the presence of GO. The synthesized nanocomposites were characterized by X-ray diffractometry (XRD), Scanning electron microscopy (SEM), and FT-IR spectroscopy. The formation of GO was confirmed by the C(002) peak at 9.39° in the XRD pattern. XRD pattern of the nanoparticles confirms the formation of crystalline Fe3O4 nanoparticles, and the diffraction peak corresponds to graphene oxide disappear in the GO/ Fe3O4 due to the absence of the folded structure of graphene oxide. SEM image of GO shows the crumpled and wrinkled lamellae structure of graphene oxide, and the images of GO/ Fe3O4 show the distribution of Fe3O4 nanoparticles with an average size of 107 nm on GO where the folded structure of GO was not present while restacking of the nanosheets, was observed. FT-IR spectrum of GO shows the presence of polar oxygenated functional groups such as carboxylic acid (-COOH), hydroxyl (-OH), and epoxy (-COC-). The photocatalytic performance of the photocatalysts was evaluated on photodegradation of methylene blue under visible light irradiation. The GO/ Fe3O4 shows better adsorption behaviour and excellent photocatalytic activity where it could be successfully used for three cycles without significant activity loss. The rate constant for the degradation of MB (0.0187 min-1 ) at the first cycle decreased to 0.0101 min-1 at the third cycle. The conversion of MB decreased from 98.31% at the first cycle to 92.15% at the third cycle. The drop in the conversion is only 6.16% going from cycle 1 to 3, which could be due to the accumulation of the MB molecules at the pore structure. The obtained high photocatalytic activity could be due to the enhanced charge separation resulted due to the presence of GO sheets and better interactions between GO and Fe 3O4.
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One pot synthesis of α-Fe2O3/turbostratic carbon composites and their photocatalytic activity under sunlight
(Elsevier, 2021-10-01) Thambiliyagodage, C. J; Nakandala, S; Siriwardana, B; Lansakara, B
Sucrose naturally obtained from sugar cane was catalytically graphitized by incorporation of varying amounts of iron (1, 5, 7.5 and 10%) as a one-pot synthesis. The weight of iron was varied relative to the weight of sucrose. Synthesized sucrose-Fe2O3 nanocomposites (FeGC) were characterized by X-ray diffractometry (XRD), Raman spectroscopy, and UV-Visible spectroscopy. It is observed that turbostratic carbon is produced upon the incorporation of iron and the percentage of graphitization increase with increasing loading of iron as revealed by XRD analysis. Quantitative analysis of Raman spectra confirm that the ordering of carbon increase with increasing loading of iron. The equilibrium adsorption capacity of carbon with the highest iron loading (10FeGC), 0.50 mg/g is higher than that with carbon without any metal, AC (0.2 mg/g), and the highest adsorption capacity (0.58 mg/g) resulted in carbon with 5% iron (5FeGC). Methylene blue adsorption to AC and carbon with 1% iron (1FeGC) followed pseudo-first-order kinetics and carbon materials with 5, 7.5 and 10% iron followed pseudo-second-order kinetics. The initial rate constant for the photodegradation of methylene blue in the presence of AC was 0.001 min−1 and that of 1FeGC (0.005 min−1) increased with increasing loading of iron where the highest initial rate constant (0.158 min−1) was obtained with 10FeGC. Ordered carbon enhances photocatalytic activity by being photoactive and increasing the separation of charges generated at α-Fe2O3.
Open Access
Leaching of ilmenite to produce titanium based materials: a review
(Springer International Publishing, 2021-12) Thambiliyagodage, C. J; Wijesekera, R; Bakker, M. G
Naturally available ilmenite mineral is being used as a starting material to produce titanium based products that have wide applications. Transformation of ilmenite to diferent titanium based materials by strong and weak acid, and base digestion, is discussed. Efects of temperature, concentration of acid/base, reaction time on dissolution of ilmenite are extensively reviewed. Characterization of the starting materials, intermediates and the products by x-ray difraction, thermogravimetry, brunauer–emmett–teller surface area analysis, and scanning electron microscopy are presented. Further, advantages and disadvantages associated with the digestion methods are discussed.
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Efficient photodegradation activity of α-Fe2O3/Fe2TiO5/TiO2 and Fe2TiO5/TiO2 nanocomposites synthesized from natural ilmenite
(Elsevier, 2021-12-01) Thambiliyagodage, C. J; Usgodaarachchi, L; Shanitha, M; Wijesekera, R; Lansakara, B; Bakker, M
Photocatalysis is an attractive widely used environmental remediation technique. Ternary (α-Fe2O3/Fe2TiO5/TiO2) and binary (Fe2TiO5/TiO2) nanocomposites were successfully synthesized by using natural ilmenite sand as the raw material. The synthesized nanocomposites were characterized by microscopic and spectroscopic analytical techniques. Both nanocomposites were catalytically active for the photodegradation of methylene blue upon irradiation by a light source (LED and sunlight). The visible light absorption of both composites was improved by the presence of Fe2TiO5 and α-Fe2O3 which absorb in the visible. The ternary nanocomposite with type II band alignments was more active than the binary nanocomposite with type I band alignment in the visible light exposure. Under sunlight exposure, binary nanocomposites were more active than the ternary nanocomposites. Band alignment, percentage of TiO2 in the composites and the proper formation of the structure of the composites govern the photocatalytic activity. OH● is suggested as the main species responsible for the photodegradation of methylene blue.
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Activity enhanced TiO2 nanomaterials for photodegradation of dyes-A review
(Elsevier, 2021-12-01) Thambiliyagodage, C. J
Wastewater generation due to anthropogenic activities has become a tremendous problem that the world is struggling to solve. Dyes release to normal water reservoirs badly impacts the environment causing severe issues. Removal of dyes from wastewater streams is important. The advanced oxidation process is advantageous as the dye molecules are degraded into harmless species. TiO2 is the most promising semiconductor that has been researched. However, the use of it in the visible range is restricted due to its high band gap (3.0 eV). TiO2 has been modified in order to enhance visible light sensitivity. This review mainly focused on the effects of doping TiO2 with metals and non-metals and coupling with metal and non-metal oxides to improve its efficiency in photodegrading dyes. TiO2 doped with Fe, Cu and Ag as the main metal species, N, S, and C as the main non-metals are summarized. Further, the effect of doping with multi non-metals and co-doping of metals and non-metals are also discussed. Moreover, coupling TiO2 with metal oxides and graphene oxide for enhanced photocatalytic activity is also summarized in this review.
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Efficient removal of methylene blue by turbostratic carbon/Fe3C/Fe composite synthesized by catalytic graphitization of sucrose
(Elsevier, 2021-12-07) Thambiliyagodage, C. J; Usgodaarachchi, L
Turbostratic carbon/Fe3C/Fe composite was prepared by catalytic graphitization of sucrose by α-Fe2O3. The synthesized composites were characterized by X-ray diffractometry (XRD), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). XRD patterns revealed the formation of turbostratic carbon with a d spacing of 0.3412 nm and the presence of Fe3C and Fe nanoparticles. Raman spectrum exhibited the D, G and G' peaks. XPS analysis shows the presence of graphitic carbon and +3 oxidation state of iron. Synthesized composite can remove methylene blue with an adsorption capacity of 17.8 mg/g at pH 7. Adsorption follows pseudo second order kinetics and the Langmuir isotherm model. As the synthesized composite is magnetic it could be easily separated from the mixture and could be reused effectively without significant activity loss for five cycles.
Open Access
A Meta-Analysis of Childhood Maltreatment in Relation to Psychopathic Traits
(PsyArXiv, 2021-12-17) de Ruiter, C; Burghart, M; De Silva, R; Garcia, S. G; Mian, U; Walshe, E; Zouharova, V
Psychopathy is a personality disorder characterized by a mix of traits belonging to four facets: affective (e.g., callous/lack of empathy), interpersonal (e.g., grandiosity), behavioral instability (e.g., impulsivity, poor behavioral controls), and social deviance (e.g., juvenile delinquency, criminal versatility). Several scholars have argued that early childhood maltreatment impacts the development of psychopathy, although views regarding its role in the four facets differ. We conducted a meta-analysis including 47 studies comprising a total of 349 effect sizes and 12,737 participants, to investigate the association between the four psychopathy facets and four types of child maltreatment: physical abuse, emotional abuse, neglect, and sexual abuse. We found support for a moderate link between overall psychopathy and childhood physical abuse, emotional abuse, and neglect, as well as overall childhood maltreatment. The link between psychopathy and childhood sexual abuse was small, but still significant. These associations were stronger for the behavioral and antisocial facets than for the affective and interpersonal facets of psychopathy, but nearly all associations were significant. Our findings are consistent with recently developed theories on the role of complex trauma in the development of severe personality disorders. Trauma-focused preventive and therapeutic interventions can provide further tests of the trauma-psychopathy hypothesis.
Open Access
Ligand exchange reactions and PEG stabilization of gold nanoparticles
(Elsevier, 2021-12-21) Thambiliyagodage, C. J
Gold nanoparticles (Au NPs) were synthesized by the citrate reduction method. Au NPs were aggregated when mixed with mercaptoethanol (ME), dopamine (DAH) and adenine (AD) as the surface passivating citrate molecules were incompletely but heavily replaced by them as supported by the occurrence of a new peak at a longer wavelength and eventual disappearance of the peak/s in the UV–Visible spectra due to the settlement of the aggregated NPs. Transmission electronic microscopic (TEM) images showed aggregated NPs. AD was increasingly replaced by an increasing concentration of dithiothreitol (DTT) in the range of 20 μM–10 mM, but an incomplete replacement was resulted even after using highly concentrated DTT (10 mM). mPEGSH passivates the gold surface where they bind to the gold surface via a mushroom-like configuration. mPEGSH stabilizes the Au NPs preventing aggregation upon mixing with ME, DAH and AD, as revealed by no change in the position and the absorbance of the localized resonance surface plasmon peak in the UV–Visible spectra and well-dispersed Au NPs in the TEM images. Mushroom-like arrangement of mPEGSH on the Au NPs allow adsorption of ME, DAH and AD as revealed by the surface enhanced Raman spectroscopic data.
Open Access
Ball milling–A green and sustainable technique for the preparation of titanium based materials from ilmenite
(Elsevier, 2022-01-01) Thambiliyagodage, C. J; Wijesekera, R
Ilmenite is a naturally available mineral that is highly applicable in the synthesis of pure TiO2. Titania mainly presents in four polymorphs as rutile, anatase, brookite and TiO2–B. Titania could be mined from minerals such as ilmenite, leucoxene and rutile among which ilmenite is the main source. Ball milling is a mechanical activation method used before subjecting ilmenite to chemical treatment methods to produce titanium based materials. Effect of milling time, milling intensity, milling atmosphere, the introduction of reducing agents on the particle size, surface area, annealing temperature, and the crystal structure of the products are reviewed. The effect of ball milling on acid digestion of ilmenite in hydrochloric acid and sulfuric acid is discussed. Further, the effect of mechanical activation on hydrothermal treatment of ilmenite is explained in detail.
Open Access
Ligand exchange reactions and PEG stabilization of gold nanoparticles
(Elsevier, 2022-01-01) Thambiliyagodage, C. J
Gold nanoparticles (Au NPs) were synthesized by the citrate reduction method. Au NPs were aggregated when mixed with mercaptoethanol (ME), dopamine (DAH) and adenine (AD) as the surface passivating citrate molecules were incompletely but heavily replaced by them as supported by the occurrence of a new peak at a longer wavelength and eventual disappearance of the peak/s in the UV–Visible spectra due to the settlement of the aggregated NPs. Transmission electronic microscopic (TEM) images showed aggregated NPs. AD was increasingly replaced by an increasing concentration of dithiothreitol (DTT) in the range of 20 μM–10 mM, but an incomplete replacement was resulted even after using highly concentrated DTT (10 mM). mPEGSH passivates the gold surface where they bind to the gold surface via a mushroom-like configuration. mPEGSH stabilizes the Au NPs preventing aggregation upon mixing with ME, DAH and AD, as revealed by no change in the position and the absorbance of the localized resonance surface plasmon peak in the UV–Visible spectra and well-dispersed Au NPs in the TEM images. Mushroom-like arrangement of mPEGSH on the Au NPs allow adsorption of ME, DAH and AD as revealed by the surface enhanced Raman spectroscopic data.
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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.