Dr Swati Pandya
@spuvvn.edu
Assistant Professor, Department of Physics, Sardar Patel University
Sardar Patel University
RESEARCH INTERESTS
Experimental Condensed Matter Physics
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Paras Lad, Vidhi Pathak, M.P. Deshpande, and Swati Pandya
Elsevier BV
Zubin R. Parekh, M.P. Deshpande, Sandip V. Bhatt, Rohitkumar M. Kannaujiya, Swati J. Pandya, and S.H. Chaki
Elsevier BV
Yash V. Joshi, M.P. Deshpande, S.H. Chaki, and Swati J. Pandya
Elsevier BV
Nidhishree M Suchak, M P Deshpande, Hiral M Mistry, Swati J Pandya, S H Chaki, and Sandip V Bhatt
IOP Publishing
Abstract Activated carbon (AC) exhibits limited adsorption capacity for pollutants. Conversely, titanium dioxide (TiO2) demonstrates excellent photocatalytic performance, making it a popular choice for pollutant removal. This study investigates the removal of methylene blue (MB) dye from wastewater using AC, TiO2@AC-2, and TiO2@AC-10 samples via adsorption and photocatalysis. The Energy Dispersive analysis of x-rays (EDAX) has confirmed the presence of Ti, C and O in the prepared samples without any impurities. All the diffraction peaks in x-ray diffractograms indicated the presence of pure anatase TiO2 (tetragonal phase) with no evidence of any other phase. Fourier transform infrared spectroscopy (FTIR) analysis identified a peak around 545 cm−1 in the TiO2@AC-2 sample, indicative of O-Ti-O stretching vibrations. This peak shifted to 602 cm−1 in the TiO2@AC-10 sample. Raman spectroscopy confirmed the presence of carbon (D and G bands) at 1310–1347 cm−1 and 1582–1597 cm−1. Additionally, characteristic Raman active bands for anatase TiO2 were observed at 154 cm−1 (Eg), 204 cm−1 (Eg), 398 cm−1 (B1g), 508 cm−1 (A1g), and 628 cm−1 (Eg). N2 adsorption–desorption isotherms revealed a mesoporous structure for all samples (AC, TiO2@AC-2, and TiO2@AC-10) with hysteresis loops, indicating pores ranging from 2 nm to 50 nm in diameter. Reflectance spectra of TiO2@AC-2 and TiO2@AC-10 displayed absorption edges at 368 nm and 385 nm, respectively, corresponding to a direct band gap of approximately 3.22 eV. Subsequently, these prepared samples were effectively employed for the removal of methylene blue (MB) dye from wastewater utilizing both adsorption and photocatalysis method. Under dark conditions, 20 mg L−1 doses of TiO2@AC-2 and TiO2@AC-10 resulted in 60% and 36% dye adsorption within 60 min respectively. In the presence of UV radiation, the degradation of dye was observed to be 74% and 95% by TiO2@AC-2 and TiO2@AC-10 respectively. This observation indicates that TiO2 nanoparticles along with AC leads to enhanced photocatalytic activity. The Langmuir–Hinshelwood model reveals lower rate constants for AC compared to the composite samples. This is likely because AC lacks inherent catalytic activity, requiring UV light to trigger adsorption. Conversely, TiO2@AC-10 exhibits the highest rate constants (K1 = 24.25 × 10−3 min−1 and K2 = 82.71 × 10−3 min−1), aligning with its higher TiO2 content confirmed by EDAX analysis. This suggests a significantly faster photocatalytic rate and superior degradation efficiency, even at a low sample concentration (20 mg L−1).
Yash V. Joshi, M.P. Deshpande, Hiteshkumar R. Bhoi, Zubin R. Parekh, S.H. Chaki, and Swati J. Pandya
Elsevier BV
Zubin R. Parekh, M. P. Deshpande, Sandip V. Bhatt, Rohitkumar M. Kannaujiya, Hiteshkumar R. Bhoi, Yash V. Joshi, S. H. Chaki, and Swati J. Pandya
Royal Society of Chemistry (RSC)
Looking at the literature survey, this seems to be the first report on growth of a copper antimony diselenide (CuSbSe2) single crystal with a 5.8 cm length and 1.0 cm diameter by the vertical Bridgman technique.
Yash V. Joshi, M.P. Deshpande, Hiteshkumar R. Bhoi, Zubin R. Parekh, S.H. Chaki, and Swati J. Pandya
Elsevier BV
Vidhi Pathak, Paras Lad, M. P. Deshpande, and Swati Pandya
Springer Science and Business Media LLC
S. Pandya, V. K. Pathak, P. D. Lad, and M. P. Deshpande
Springer Nature Singapore
Vidhi Pathak, Paras Lad, Anjali B. Thakkar, Parth Thakor, M.P. Deshpande, and Swati Pandya
Elsevier BV
Zubin R. Parekh, M.P. Deshpande, Sandip V. Bhatt, Hiteshkumar R. Bhoi, Rohitkumar M. Kannaujiya, Yash V. Joshi, Swati J. Pandya, and S.H. Chaki
Elsevier BV
Hiral M. Mistry, M.P. Deshpande, Anilkumar B. Hirpara, Nidhishree M. Suchak, Sunil H. Chaki, Swati Pandya, Jignesh Valand, and Sandip V. Bhatt
Elsevier BV
Swati Pandya, L. S. Sharath Chandra, and V. Ganesan
Springer Science and Business Media LLC
Nidhishree M Suchak, Hiral M Mistry, Hiteshkumar R Bhoi, M P Deshpande, Swati J Pandya, S H Chaki, Manisha Tiwari, Dhermendra K Tiwari, and Sandip V Bhatt
IOP Publishing
Abstract The synergetic effect of photocatalytic, adsorption and antibacterial properties of ZnO@ACP and CuO@ACP samples are investigated in this study. The synthesized samples are initially studied for their elemental composition, crystalline phase and structure, surface morphology, optical band gap, functional groups, vibrational modes by EDAX, SEM, XRD, Raman, FTIR, UV–vis spectroscopy and BET respectively. Methylene blue (MB) which is used as a dye in industries has been used in this work for its removal from waste water using the above prepared samples. We could remove 63% of MB by adsorption under dark conditions with this samples. After illumination with UV radiation, it is seen that MB is degraded 93% by ZnO@ACP, 85% with CuO@ACP whereas adsorbed 78% with activated charcoal. This reflects that ZnO and CuO nanoparticles embedded with activated charcoal shows increase in photocatalytic activity. Further, Langmuir-Hinshelwood model is used to calculate the kinetic rates of ZnO and CuO nanoparticles on embedded on ACP samples. The antimicrobial activity of synthesized samples is also tested against E. coli. bacteria whereas cell viability is tested using CHO (Chinese hamster ovary) animal cells at various concentrations. The results obtained shows 75% decrease in the growth of E. coli bacteria for ZnO@ACP and 60% decrease for CuO@ACP at a concentration of 250 μg ml−1 whereas reduction in colony counts is 95% and 75%, respectively. we obtained 80%–90% CHO cell viability proves that both these samples are not toxic to these cells.
Paras Lad, Vidhi Pathak, Anjali B. Thakkar, Parth Thakor, M. P. Deshpande, and Swati Pandya
Springer Science and Business Media LLC
Vidhi Pathak, Paras Lad, Anjali B. Thakkar, Parth Thakor, M.P. Deshpande, and Swati Pandya
Elsevier BV
Piyush Rajput, M. P. Deshpande, Hiteshkumar R. Bhoi, S. H. Chaki, Swati J. Pandya, Manish Mishra, Vasant Sathe, Suman Das, Dhermendra K. Tiwari, and Sandip V. Bhatt
World Scientific Pub Co Pte Ltd
Pure and La-doped titania nanoparticles are prepared by the chemical precipitation method. The stoichiometry of prepared samples is confirmed by EDAX whereas XRD analysis showed rutile tetragonal phase of synthesized pure TiO2 and La (2%, 4%, 6% and 8%)-doped titanium dioxide nanoparticles. The crystallite size of all samples lies below 50[Formula: see text]nm as calculated from XRD. All the samples show cuboid/ellipsoidal polyhedral kind of morphologies of nanoparticles except La 2% TiO2 which exhibits nanoflex morphology as seen in TEM images. Raman spectra recorded from low temperature to room temperature have shown [Formula: see text], [Formula: see text] and [Formula: see text] fundamental modes supporting the rutile tetragonal structure as reported in XRD. The absorption edge in the UV-Visible spectra of doped samples is shifted towards higher values of wavelength with increase of La in TiO2. Photoluminescence spectra at various excitation energies showed the changes in PL intensity as La content is increased. Photocatalytic activity for the constant time interval for pure TiO2 shows better photodegradation efficiency in comparison to the La-doped TiO2. Antibacterial activity of pure TiO2 is seen to be improved with La doping of 8%-doped TiO2 nanoparticles.
Hiteshkumar R. Bhoi, M.P. Deshpande, Piyush Rajput, Shivam Patel, Kiran N. Patel, S.H. Chaki, Swati J. Pandya, and V.G. Sathe
Elsevier BV
Piyush Rajput, M.P. Deshpande, Hiteshkumar R. Bhoi, Nidhishree M. Suchak, Prachi H. Desai, S.H. Chaki, Swati J. Pandya, Manish Mishra, Sandip V. Bhatt, Dhermendra K. Tiwari,et al.
Elsevier BV
Ranjan Kr. Giri, Sunil Chaki, Ankurkumar J. Khimani, Yati H. Vaidya, Parth Thakor, Anjali B. Thakkar, Swati J. Pandya, and Milind P. Deshpande
American Chemical Society (ACS)
A simple hydrothermal route is employed to synthesize pure copper indium disulfide (CIS) and CIS nanoparticles (NPs) mediated by various natural plant extracts. The plant extracts used to mediate are Azadirachta indica (neem), Ocimum sanctum (basil), Cocos nucifera (coconut), Aloe vera (aloe), and Curcuma longa (turmeric). The tetragonal unit cell structure of as-synthesized NPs is confirmed by X-ray diffraction. The analysis by energy-dispersive X-rays shows that all the samples are near-stoichiometric. The morphologies of the NPs are confirmed by high-resolution scanning and transmission modes of electron microscopy. The thermal stability of the synthesized NPs is determined by thermogravimetric analysis. The optical energy band gap is determined from the absorption spectra using Tauc’s equation. The antimicrobial activity analysis and the estimation of the minimum inhibitory concentration (MIC) value of the samples are performed for Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris, Enterobacter aerogenes, and Staphylococcus aureus pathogens. It shows that the aloe-mediated CIS NPs possess a broad inhibitory spectrum. The best inhibitory effect is observed against S. aureus, whereas the least effect was exhibited against P. vulgaris. The least MIC value is found for aloe-mediated CIS NPs (0.300 mg/mL) against S. aureus, P. aeruginosa, and E. aerogenes, along with basil-mediated NPs against E. coli. The antioxidant activity study showed that the IC50 value to inhibit the scavenging activity is maximum for the control (vitamin C) and minimum for pure CIS NPs. The in vivo cytotoxicity study using brine shrimp eggs shows that the pure CIS NPs are more lethal to brine shrimp than the natural extract-mediated CIS NPs. The in vitro cytotoxicity study using the human lung carcinoma cell line (A549) shows that the IC50 value of turmeric extract-mediated CIS NPs is minimum (15.62 ± 1.58 μg/mL). This observation reveals that turmeric extract-mediated CIS NPs are the most potent in terms of cytotoxicity toward the A549 cell line.
Nidhishree M Suchak, Prachi H Desai, M P Deshpande, S H Chaki, Swati J Pandya, Anju Kunjadiya, and Sandip V Bhatt
IOP Publishing
Pure and polymer coated (PVP and PVA) gold nanoparticles (AuNPs) with 0.001 and 0.002 M concentrations were synthesised by chemical method. Transmission electron microscopy (TEM) images showed that the size of nanoparticles is below 50 nm whereas the selected area electron diffraction (SAED) pattern indicated cubic structure with lattice parameter of 4.09 Å for each sample. The absorption bands for all these samples lie between 500 and 550 nm as observed from UV–vis spectra. The photoluminescence (PL) spectra taken at 300 nm excitation wavelength showed emission between 415 and 430 nm whereas the particle size determined from particle size analyser lies below 100 nm for all samples. The ultrasonic velocity measured as a function of temperature showed the decrement above 50 °C for PVP and PVA coated AuNPs. The antimicrobial activity for these above taken concentrations of gold samples showed negative effect, whereas higher concentration of AuNPs of 0.005 M showed the positive effect for gram-positive and gram-negative bacteria.
Nitu Katariya, L. S. Sharath Chandra, Swati Pandya, Bhavana Singh, S. B. Shrivastava, and V. Ganesan
AIP Publishing
Krishna Chauhan, M.P. Deshpande, Kiran N. Patel, Piyush Rajput, Hiteshkumar R. Bhoi, S.H. Chaki, and Swati Pandya
Elsevier BV
Swati Pandya, L S Sharath Chandra, and V Ganesan
IOP Publishing
We report here on the resistivity (ρ) and heat capacity (Cp) on Nd1−xGdxCo2 (with 0 ⩽ x ⩽ 1) down to 2 K and up to 14 T. Distinct changes were observed in all measured properties across the paramagnetic to ferromagnetic transition along with the cubic to tetragonal transition (Tc = 100 K for x = 0 and Tc = 400 K for x = 1), and across the spin reorientation transition along with the tetragonal to orthorhombic transition (Tsr = 42 K x = 1, and Tsr = 70 K for x = 0.8). Both the transitions are associated with a significant change in entropy due to the coupling of the magnetic and structural transitions. The external magnetic field causes both the transitions to occur at higher temperatures, leading to large magneto caloric as well as large magneto resistance effects. Hence, Gd substitution in the site of Nd hints at the functionality of these doped materials near room temperature. However, near a concentration of 0.4 ⩽ x ⩽ 0.5, an anomalous behavior of the tetragonal to orthorhombic transition for the externally applied magnetic field is observed.
Krishna Chauhan, M P Deshpande, Kiran N Patel, S H Chaki, and Swati Pandya
IOP Publishing
Nanoparticles of Sb2−x BixS3 (x = 0.0, 0.002, 0.006, 0.01) are synthesized by chemical precipitation technique at room temperature and characterized by powder x-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive analysis of x-rays (EDAX), room temperature and low temperature Raman spectroscopy. The Rietveld refinement profiles of powder XRD patterns reveals that the prepared nanoparticles are crystallized in stibnite orthorhombic structure with Pnma space group and do not contain any other impurity phase. TEM images show nearly spherical shape of Sb2−xBixS3 (x = 0.0, 0.002, 0.006, 0.01) nanoparticles whereas selected area electron diffraction (SAED) patterns indicate polycrystalline nature. EDAX analysis confirmed the purity of the prepared nanoparticles. The different vibration modes in Sb2−xBixS3 (x = 0.0, 0.002, 0.006, 0.01) nanoparticles is studied by room temperature and low temperature (up to 80 K) Raman spectroscopy.