Study on photocatalytic and antibacterial properties of phase pure Fe2O3 nanostructures synthesized using Caralluma Fimbriata and Achyranthes Aspera leaves

Journal Pre-proof Study on Photocatalytic and Antibacterial Properties of Phase Pure Fe2 O3 Nanostructures Synthesized Using Caralluma Fimbriata and Achyranthes Aspera Leaves S. Haseena, S. Shanavas, J. Duraimurugan, T. Ahamad, S.M. Alshehri, R. Acevedo, N. Jayamani

PII:

S0030-4026(19)31946-1

DOI:

https://doi.org/10.1016/j.ijleo.2019.164047

Reference:

IJLEO 164047

To appear in:

Optik

Received Date:

2 October 2019

Revised Date:

6 December 2019

Accepted Date:

10 December 2019

Please cite this article as: Haseena S, Shanavas S, Duraimurugan J, Ahamad T, Alshehri SM, Acevedo R, Jayamani N, Study on Photocatalytic and Antibacterial Properties of Phase Pure Fe2 O3 Nanostructures Synthesized Using Caralluma Fimbriata and Achyranthes Aspera Leaves, Optik (2019), doi: https://doi.org/10.1016/j.ijleo.2019.164047

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Study on Photocatalytic and Antibacterial Properties of Phase Pure Fe2O3 Nanostructures Synthesized Using Caralluma Fimbriata and Achyranthes Aspera Leaves

S. Haseenaab, S. Shanavasc, J. Duraimurugand, T. Ahamade, S. M. Alshehrie, R. Acevedof and N. Jayamanib*

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Department of Physics, Muthayammal Memorial College of Arts and Science, Rasipuram,

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Tamil Nadu, India. Department of Physics, Government Arts College (Autonomous), Salem - 636007, Tamil

Nadu, India. c

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Department of Physics, Periyar University, Salem- 636 011, India.

Department of Energy Studies, Periyar University, Salem- 636 011, Tamil Nadu, India.

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Department of chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh

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11451, Saudi Arabia.

Facultad de Ingeniería y Tecnología. Universidad San Sebastián, Bellavista 7, Santiago

*

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8420524, Chile.

Corresponding Author

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Email address: [email protected]; [email protected] (N. Jayamani);

Graphical Abstract

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Abstract

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This research demonstrates the synthesis of phase pure Fe2O3 nanoclusters using Caralluma Fimbriata and Achyranthes Aspera as reducing and stabilizing agents. The structure

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and physicochemical property of the nanoparticles are characterized by X-Ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), Ultraviolet Diffuse Reflectance

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Spectroscopy (UV-DRS), Field Emission Scanning Electron Microscopy (FESEM) and HighResolution Transmission Electron Microscopy (HRTEM) analysis. The HRTEM results

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reveals that the particle size of C. Fimbriata and A. Aspera treated Fe2O3 nanoparticles were found to be ~25 nm and ~22 nm, respectively. The photocatalytic degradation and reusable of the

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green treated Fe2O3 Nanoparticles were performed by the photodegradation of Methylene Blue (MB) dye solution under solar light irradiation. In addition, green synthesized Fe2O3 nanoparticles assayed against gram-negative bacteria Escherichia coli (E.coli). Keywords: Caralluma Fimbriata; Achyranthes Aspera; Fe2O3; Catalyst; Methylene Blue.

1. Introduction: Wastewaters produced from dye industrial and dye overshadowing industries have always been a problem of ecological concern [1]. In this regard, the extract of green plant leaves occurred biosynthesis of semiconductor nanoparticles has been widely investigated by numerous recent articles [2–6]. In line with the concept of green chemistry, the use of solar energy has been an interesting impulse toward the progress of novel photo-based synthetic technologies to drive several chemical reactions [7-15]. Nowadays, organic contaminants in

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wastewater consist of main ecological issues due to highly toxic and difficult to degrade in nature [16]. Dyes were mostly riotous organic compounds that cannot be simply detached by biological degradation techniques. Though, the use of non-biological approaches, such as

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photocatalytic degradation method, could result in acceptable removal. Hence, it is essential to work suitable catalytic agent to remove dyes in contaminant wastewater. So, a typical organic

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contaminant methylene blue (MB), which can be degraded in aqueous media using Fe2O3

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nanostructures because they are highly stable and magnetically recoverable [17]. There has been much attention in the development of synthetic methods to produce one-dimensional Fe2O3 nanostructures, physical vapor deposition, hydrothermal technique, chemical vapor

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deposition and the sol-gel process [18-21]. The vapor system generally involves unusual equipment and high temperatures; however, the techniques using templates or substrates often

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meet problems with preconstruction and post-removal of contaminations. Therefore, the rapid

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preparation of highly crystalline Fe2O3 nanoparticles by a simple and one-step hydrothermal method with the green leaves extract, particularly towards improving degradation efficiency [22]. To this end, we emphasize a simple technique for the preparation of Fe2O3 nanoparticles (Nanoparticles) by an aqueous green extract of Caralluma Fimbriata (C. Fimbriata) and Achyranthes Aspera (A. Aspera) as reducing agent as well as capping agent [23-27]. The prepared Fe2O3 nanoparticles have shown admirable photocatalytic and antibacterial activity.

We hope that this present research can provide as a basis for further design of Fe2O3 Nanoparticles catalyst for water purification and photochemical water splitting applications. 2. Experimental Section 2.3 Green Synthesis of Fe2O3 Nanoparticles Initially, the green extract solution is prepared by the same procedure explained by Duraimurugan et al. [22]. 10 ml of green leaf extracts were vigorously added to a 20 ml of 1M FeCl3 and annealed to 80 C with continuous magnetic stirring for 10 min. The development

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of Fe2O3 Nanoparticles was specified by the presence of brownish-red color. The synthesized nanoparticles were washed several times through centrifugation with DI to remove impurities

2.4 Characterization of Fe2O3 Nanoparticles

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and then dried for further studies.

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X-Ray Diffraction Analysis (XRD) was recorded on a Shimadzu X-ray diffractometer with Cu-Kα (λ=1.5406 Å) radiation. Fourier Transform Infrared spectra (FTIR) were obtained

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on IR Prestige-21 Shimadzu Spectrophotometer. UV–vis DRS spectra were recorded on Fe2O3 Nanoparticles in range of 200–800 nm wavelength using a PerkinElmer Lambda 950 UV-vis

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spectrometer. The morphologies and elemental analysis of the samples were investigated by a JEOL-2010 high-resolution transmission electron microscope (HRTEM) working at 200 kV, a

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JSM-6700F field emission scanning electron microscope (FESEM) working at 20 kV and EDS (JEOL-JSM-6490LA SEM, Tokyo, Japan).

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3. Results and Discussion 3.1. XRD Patterns

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Fig. 1: XRD patterns of C. Fimbriata and A. Aspera mediated Fe2O3 Nanoparticles.

The XRD patterns of Fe2O3 synthesized using the C. Fimbriata and A. Aspera leaves

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extract in Fig. 1. Evidently confirms the crystalline phase of the rhombohedral symmetry

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nanoparticles with lattice constants a = 0.5035 and c = 1.3740 nm (JCPDS card number 89-0596). The crystalline phase of the green treated Fe2O3 photocatalyst suggests that the rhombohedral-

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shaped Fe2O3 would be uniformly dispersed over the whole surface. The average crystallite size to the reflection planes for the prepared nanoparticles have been determined by the Debye

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Scherrer formula [28]. The average crystallite size has been calculated to be ~24.6 nm and 22.2 nm for C. Fimbriata treated Fe2O3 (CFO) and (A. Aspera) treated Fe2O3 (AFO) nanoparticles,

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respectively.

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3.2. FTIR Analysis

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Fig. 2: FTIR spectra of CFO and AFO nanoparticles.

FTIR analysis was carried out within the range 400-4000 cm-1. An assessment of the

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FTIR spectra of the Fe2O3 prepared using the C. Fimbriata and A. Aspera leaf extract (Fig. 2) can provide evidence about the functional groups of leaf extracts liable for capping and

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reducing the Fe2O3 nanoparticles. The absorption band at ~3427 cm-1 was found to be adsorbed water moiety [28]. The peaks corresponding to –C=C-,–C-O-C, O-H, and C=C bonds were

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originated from biomolecules from plant extracts such as flavonoids, alkaloids, and polyphenols present in C. Fimbriata and A. Aspera leaf. The prominent bands at 455 cm-1 and

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557 cm-1 observed in the spectra can be attributed to Fe-O vibrational modes [29,30].

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3.3. Morphological Analysis

Fig. 3: FESEM images of (a&b) CFO, and (c&d) AFO nanoparticles with different magnifications

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Fig. 4: EDX spectrum of CFO nanoparticles

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Fig. 5: HRTEM images of (a&b) CFO (d&e) AFO Nanoparticles with different magnifications

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and (e&f) SAED patterns of CFO and AFO nanoparticles. The FESEM micrographs of CFO and AFO nanoparticles were shown in Fig. 3. The

aspects of the appearance of the surface of microstructures were visibly discriminable and seem very smooth which leads to the availability of high surface area for catalytic activity. The EDX spectrum demonstrates the elemental conformation of the CFO nanoparticles. The EDX spectrum exhibited the presence of Fe and O (Fig. 4). The morphology of the CFO and AFO nanoparticles have been further investigated by HRTEM. The particles (fig. 5) perform to be

uneven in shape. The precise particle size and shape of the prepared nanoparticles were examined by HRTEM (Fig. 5). The HRTEM results of both CFO and AFO nanoparticles exhibited that the particles have rhombohedral morphologies and polydisperse in nature [31]. The particle size of CFO and AFO nanoparticles were found to be ~25 nm and ~22 nm, respectively. The SAED patterns show the number of concentric rings having bright dots. The ring arrangements in the SAED pattern match to the XRD planes of CFO and AFO nanoparticles (JCPDS No. 89-0596).

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3.4 Optical Characterization Fig. 6a. shows the UV-Vis absorption spectra of the CFO and AFO nanoparticles. The green treated Fe2O3 NPs exhibits typical absorption peaks at UV region of UV-Vis DRS

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spectra. The bandgap energy of a Fe2O3 NPs can be calculated by Tauc relation [16]. The UVVis spectrum shows wider absorption in the visible region for both CFO and AFO nanoparticles

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[19]. The bandgap energies of the CFO and AFO nanoparticles can be estimated from the plots

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of (αhν)2 versus photon energy (hν) as shown in Fig. 6b. It was observed that the bandgap

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energy of the CFO and AFO nanoparticles were 2.26 and 2.27 eV, respectively.

Fig. 6: (a) UV-visible DRS spectra and (b) Plots of (αhν)2 vs photon energy (hν) for the bandgap energy of CFO and AFO nanoparticles

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3.5. Photocatalytic Degradation of MB dye

Fig. 7: UV–vis spectra of MB removal at different time intervals: (a) CFO (b) AFO

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nanoparticles, (c) MB removal rate at the different photocatalytic system, (d) The kinetics plots

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for the pseudo-first-order reaction of MB decolorization.

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Fig. 8: Cycling degradation curve for (a) CFO (b) AFO nanoparticles. The degradation activity of the prepared CFO and AFO nanoparticles was confirmed

on MB dye. Significant decrease in the absorption intensity with increasing irradiation time was perceived, which are shown in Fig. 7 (a&b) respectively for MB dye [34-35]. There was no new absorption present throughout the entire process showed the complete photolysis in the occurrence of the suggested green synthesized Fe2O3 Nanoparticles. No removal of the dye

was detected in absence of the catalyst and very slow removals were detected in the dark. When illuminated in solar light, the predominant peak at 663 nm decreased with the photocatalytic degradation reaction time, revealing that the MB solution was degraded rapidly in the photocatalytic degradation reaction within 30 min. The photocatalytic degradation rate of MB molecules in the presence of both CFO and AFO nanoparticles is shown in Fig. 7c. Also kinetic can often follow pseudo-first-order kinetics, which is represented in Fig. 7d [32]. The rate constants for MB dye using Fe2O3 as photocatalyst; 0.9766. The mechanism of removal of dye

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has been studied earlier [33,34]. When the CFO and AFO nanoparticles nanoparticles is illuminated by visible light irradiation, the photoexcited conduction band electrons in Fe2O3 nanoparticles can react with the dissolved O2 molecules in the degradation reaction solution to

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produce superoxide radical anions, O2–•. The photo-induced holes in the valence band of green treated Fe2O3 nanoparticles can react with OH– groups to form OH• radicals or oxidize dye

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molecules flexibly[35-36]. The recyclability of the Fe2O3 Nanoparticles was examined, as

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shown in Fig. 8(a&b). The photocatalyst after the degradation reaction is collected and used again to check its photocatalytic stability and recyclability. It can be evidently seen that the photocatalytic ability of CFO and AFO nanoparticles was not affected very high even after four

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consecutive cycles which display the admirable reusability of catalyst[37-39].

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3.6. Photocatalytic degradation mechanism

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Fig. 9: Photocatalytic mechanism of green treated Fe2O3 nanostructure.

Based on the results from the optical analysis of CFO and AFO nanoparticles the

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mechanism is proposed in Fig. 9. During photocatalytic process, when the photocatalytic

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materials are illuminated by visible light irradiation the electrons from valence band (VB) of Fe2O3 nanoparticles will get excited to the conduction band (CB). When the electrons get

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excites the holes will remain in the valance band of Fe2O3 nanoparticles and the holes at the valence band of Fe2O3 nanoparticles will react with OH in the reaction solution to produce

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hydroxyl radicals (•OH) [22-24]. On another hand, the photoexcited electrons from VB to CB will react with the dissolved oxygen in the photocatalytic degradation reaction solution to

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produce superoxide radicals (O2-•). The band edge position of photocatalytic materials plays major role in the production of superoxide and hydroxide radicals. Based on the equation given

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by shanavas et al. [16]. The VB and CB energy of CFO and AFO nanoparticles were found to be (0.25 eV and 2.51 eV) and (0.245 eV and 2.525 eV), respectively. The valance band potential of Fe2O3 nanoparticle is well higher than oxidation potential of OH into •OH. And so the ability of Fe2O3 nanoparticles to produce hydroxyl radicals are also very high[40,41]. 3.7. Antimicrobial assay

Fig. 10: Antibacterial performance test for C. Fimbriata and A. Aspera mediated Fe2O3

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nanoparticles materials towards gram-negative E. coli pathogen. The antibacterial activity of the CFO and AFO nanoparticles were examined using the agar-agar diffusion method [22]. Fig. 10 (a&b) shows that the Fe2O3 nanoparticles show

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significant antibacterial activity against Gram-negative (E. coli) bacterial pathogen. The growth in the diameter of zone of inhibition could be detected for both organisms on increasing

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the concentration of the nanoparticles. The method of antibacterial performance was measured from previous works of literature [35,36]. The zone of inhibition for the bacteria was nearly

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showing tremendous growth inhibition for a minimum concentration of 75 mg ml-1 for Gramnegative (E. coli) bacteria (Table 1).

Bacterial strain used

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Nanoparticles

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Table. 1: Antibacterial activity of CFO and AFO nanoparticles

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Fe2O3 (C. Fimbriata) Fe2O3 A. Aspera

Zone of inhibition level (in mm) (Mean value of four measurements) Standard The concentration of the sample (µg/mL) 3 µL 25 µg 50 µg 75 µg 12.2±1.3

13.7±3.4

20.6±1.5

30.31±1.8

9.4±1.2

13.4±2.2

18.3±1.3

30.24±1.4

E. coli

4. Conclusion In summary, the present research proposes an exclusive method for the preparation of highly pure, crystalline and biocompatible Fe2O3 Nanoparticles through the single-use of C.

Fimbriata and A. Aspera leaf extracts. The average crystallite size has been calculated to be 24.6 nm and 22.2 nm for CFO and AFO nanoparticles nanoparticles, respectively. MB dye could be easily decolorized by Fe2O3 Nanoparticles under solar light irradiation. The antibacterial efficacy of the Fe2O3 Nanoparticles against Gram-negative bacteria is also established. Furthermore, our outcomes will be possibly appropriate to many other significant semiconducting minerals and compounds.

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The authors declares there is no conflict of interest.

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Acknowledgment

The authors thanks to Researchers Supporting Project number (RSP-2019/6), King Saud

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University, Riyadh, Saudi Arabia.

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