Development of nanocoral-like Cd(SSe) thin films using an arrested precipitation technique and their application

Khot, Kishorkumar V.,Mali, Sawanta S.,Pawar, Nita B.,Kharade, Rohini R.,Mane, Rahul M.,Kondalkar, Vijay V.,Patil, Pallavi B.,Patil, Pramod S.,Hong, Chang K.,Kim, Jin H.,Heo, Jaeyeong,Bhosale, Popatrao The Royal Society of Chemistry 2014 New journal of chemistry Vol.38 No.12

<P>Nanocrystalline cadmium sulfoselenide thin films have been synthesized using a self-organized arrested precipitation technique with different deposition times using triethanolamine as a complexing agent. Optical, structural, morphological and photoelectrochemical solar cell properties were investigated as a function of deposition time. A UV-Vis-NIR absorption study suggested a direct allowed transition type and the band gap energy decreased from 2.01 to 1.86 eV with the increase in deposition time. X-ray diffraction studies revealed that the thin films are nanocrystalline by nature with a pure hexagonal crystal structure and a calculated crystallite size of 51–68 nm. Field emission scanning electron microscopy demonstrated that the surface morphology was altered from nanoflakes to assorted nanoflakes–nanospheres and finally to a nanocoral-like morphology. X-ray photoelectron spectroscopy and energy dispersive X-ray spectroscopy showed that the composition of the Cd(SSe) thin films was of good stoichiometry. Electrical conductivity and thermoelectric power measurements confirmed that the deposited films were n-type semiconductors. From <I>J–V</I> measurements, a highest photo-conversion efficiency of 0.57% was achieved. The significant boost in the PEC performance might be due to the improved crystallinity along with lower values of the grain boundary resistance, dislocation density and the microstrain of the Cd(SSe) thin films.</P> <P>Graphic Abstract</P><P>First-time synthesis of nanoflakes to nanocoral-like Cd(SSe) thin films using a novel arrested precipitation technique with triethanolamine as complexing agent (<I>η</I> = 0.57%). <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c4nj01319k'> </P>

Electrospinning: A versatile technique for making of 1D growth of nanostructured nanofibers and its applications: An experimental approach

Patil, Jyoti V.,Mali, Sawanta S.,Kamble, Archana S.,Hong, Chang K.,Kim, Jin H.,Patil, Pramod S. Elsevier 2017 APPLIED SURFACE SCIENCE - Vol.423 No.-

<P><B>Abstract</B></P> <P>One dimensional (1D) metal oxide nanostructures (1D-MONS) play a key role in the development of functional devices including energy conversion, energy storage and environmental devices. They are also used for some important biomedical products like wound dressings, filter media, drug delivery and tissue engineering. The electrospinning (ES) is the versatile technique for making of 1D growth of nanostructured nanofibers, an experimental approach and its applications. The present review is focused on the 1D growth of nanostructured nanofibers in different applications like dye sensitized solar cells, perovskite solar cells, fuel cells, lithium ion batteries, redox flow batteries, supercapacitor, photocatalytic, and gas sensors based on ZnO, TiO<SUB>2,</SUB> MnO<SUB>2,</SUB> WO<SUB>3,</SUB> V<SUB>2</SUB>O<SUB>5</SUB>, NiO, SnO<SUB>2,</SUB> Fe<SUB>2</SUB>O<SUB>3</SUB> etc. metal oxides, their composites and carbon. This review article presents an introduction to various types of ES techniques and their technical details. Also, the advantages and disadvantages of each ES technique are summarized. The various technical details such as preparative parameters, post-deposition methods, applied electric field, solution feed rate and a distance between a tip to the collector are the key factors in order to obtain exotic 1D nanostructured materials. Also, the lucid literature survey on the growth of nanostructures of various metal oxides and application in different fields are covered in this review. Further, the future perspectives has also been discussed.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Electrospinning Technique: Current state-of-the-art. </LI> <LI> 1D TiO<SUB>2</SUB> nanofibers. </LI> <LI> Experimental Approaches. </LI> <LI> Application towards energy conversion, energy storage, environmental and biomedical applications. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

High performing smart electrochromic device based on honeycomb nanostructured h-WO₃ thin films: hydrothermal assisted synthesis

Kondalkar, Vijay V.,Mali, Sawanta S.,Kharade, Rohini R.,Khot, Kishorkumar V.,Patil, Pallavi B.,Mane, Rahul M.,Choudhury, Sipra,Patil, Pramod S.,Hong, Chang K.,Kim, Jin H.,Bhosale, Popatrao N. The Royal Society of Chemistry 2015 Dalton Transactions Vol.44 No.6

<P>Herein, we report honeycomb nanostructured single crystalline hexagonal WO<SUB>3</SUB> (h-WO<SUB>3</SUB>) thin films in order to improve electrochromic performance. In the present investigation, honeycomb nanostructured WO<SUB>3</SUB> with different unit size and nanowire array with highly nanocrystalline frameworks have been synthesized <I>via</I> a hydrothermal technique. The influence of hydrothermal reaction time on the honeycomb unit cells, crystallite size, lithium ion diffusion coefficient and switching time for coloration/bleaching were studied systematically. The electrochromic study reveals that the honeycomb unit cell size has a significant impact on the electrochromic performance. Small unit cells in the honeycomb lead to large optical modulation and fast switching response. A large optical modulation in the visible spectral region (60.74% at <I>λ</I> = 630 nm) at a potential of −1.2 V with fast switching time (4.29 s for coloration and 3.38 s for bleaching) and high coloration efficiency (87.23 cm<SUP>2</SUP> C<SUP>−1</SUP>) is observed in the honeycomb WO<SUB>3</SUB> thin films with a unit cell diameter of 1.7 μm. The variation in color on reduction of WO<SUB>3</SUB> with applied potential has been plotted on an <I>xy</I>-chromaticity diagram and the color space coordinate shows the transition from a colorless to deep blue state.</P> <P>Graphic Abstract</P><P>Honeycomb nanostructured single crystalline hexagonal WO<SUB>3</SUB> (h-WO<SUB>3</SUB>) thin films in order to improve electrochromic performance. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c4dt02953d'> </P>

Visible upconversion in Er³⁺/Yb³⁺ co-doped LaAlO₃ phosphors

Singh, Vijay,Rai, V.K.,Singh, N.,Pathak, M.S.,Rathaiah, M.,Venkatramu, V.,Patel, Rahul V.,Singh, Pramod K.,Dhoble, S.J. Elsevier 2017 Spectrochimica acta. Part A, Molecular and biomole Vol.171 No.-

<P><B>Abstract</B></P> <P>The Er<SUP>3+</SUP> doped and Er<SUP>3+</SUP>/Yb<SUP>3+</SUP> co-doped LaAlO<SUB>3</SUB> phosphors have been synthesized by the combustion method and characterized their structural, morphological, elemental, vibrational and optical properties. The optical absorption and upconversion properties of the synthesized phosphors have been studied. Upon co-doping Yb<SUP>3+</SUP> ions into Er<SUP>3+</SUP>:LaAlO<SUB>3</SUB>, the blue, green and red upconversion emissions of Er<SUP>3+</SUP> ions have been enhanced about ~20, ~54 and ~22 times, under 978nm laser excitation. The observed upconversion emissions could be due to excited state absorption in Er<SUP>3+</SUP>:LaAlO<SUB>3,</SUB> whereas energy transfer is dominant mechanism in Er<SUP>3+</SUP>/Yb<SUP>3+</SUP>:LaAlO<SUB>3</SUB> phosphors. The tuning in the color emitted from the synthesized phosphors towards the green region has been found due to incorporation of the Yb<SUP>3+</SUP> ions. With increase in the pump power, the color emitted from the co-doped phosphor is not tuned significantly, showing its applicability in making the green display devices.</P> <P><B>Highlights</B></P> <P> <UL> <LI> By facile combustion synthesis, Er<SUP>3+</SUP> and Er<SUP>3+</SUP>/Yb<SUP>3+</SUP> doped LaAlO<SUB>3</SUB> phosphors are obtained. </LI> <LI> Phosphor was characterized using XRD, SEM-EDX, FTIR and Up-conversion spectroscopy. </LI> <LI> Upon excitation at 978nm, intense up-conversion emission is observed. </LI> <LI> Prepared materials could be suitable for up-conversion lasers and green display device. </LI> </UL> </P> <P><B>Graphical Abstract</B></P> <P>[DISPLAY OMISSION]</P>

Sentiment analysis of malayalam tweets using machine learning techniques

Soumya S.,Pramod K.V. 한국통신학회 2020 ICT Express Vol.6 No.4

Sentiment Analysis of Malayalam Tweets using Machine Learning techniques is done in this paper. The tweets are classified into positive and negative using different machine learning techniques such as Naive Bayes (NB), Support Vector Machine (SVM) and Random Forest (RF). The different features like Bag of Words (BOW), Term Frequency vs. Inverse Document Frequency (TF IDF), Unigram with Sentiwordnet, and Unigram with Sentiwordnet including negation words are considered for feature vector formation of input dataset. The Random Forest classifier shows higher accuracy while considering Unigram with Sentiwordnet including negation words as a feature.

Photoelectrocatalysis of Cefotaxime Using Nanostructured TiO₂ Photoanode: Identification of the Degradation Products and Determination of the Toxicity Level

Kondalkar, Vijay V.,Mali, Sawanta S.,Mane, Rahul M.,Dandge, P. B.,Choudhury, Sipra,Hong, Chang K.,Patil, Pramod S.,Patil, Shivajirao R.,Kim, Jin H.,Bhosale, Popatrao N. American Chemical Society 2014 INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH - Vol.53 No.47

<P>Nanostructured TiO<SUB>2</SUB> thin films were fabricated via a facile, economical, and energy-efficient microwave-assisted dip-coating (MWDC) technique. Further, the resulting TiO<SUB>2</SUB> films were characterized by means of X-ray diffraction, high-resolution transmission electron microscopy, selected-area electron diffraction, Fourier transform Raman spectroscopy, X-ray photoelectron spectroscopy, and photoluminescence spectroscopy techniques for their phase structure, morphology, and optical and surface properties. TiO<SUB>2</SUB>-mediated photoelectrocatalytic degradation of the antibiotic cefotaxime (CFX) in an aqueous solution was studied by varying the pH under UV illumination. The degradation intermediates and possible reaction degradation path of CFX were analyzed by electrospray ionization time-of-flight mass spectrometry (MS). The MS spectra revealed that degradation of CFX occurs through β-lactum corresponding to the cleavage of the cephem nucleus. Moreover, the antibacterial activity of CFX prior to and after photoelectrocatalytic degradation was carried out to analyze the toxicity against <I>Staphylococcus aureus</I> and salmonella typhi bacteria. Interestingly, it was observed that the antibiotic activity was drastically inhibited after photoelectrocatalytic degradation of the CFX solution. The photoelectrocatalytic stability of a nanostructured TiO<SUB>2</SUB> electrode was evaluated by recycling the degradation experiments. It was observed that there was no significant decrease in the catalytic activity, indicating potential applications of the TiO<SUB>2</SUB> electrode prepared by the MWDC method.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/iecred/2014/iecred.2014.53.issue-47/ie501821a/production/images/medium/ie-2014-01821a_0014.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ie501821a'>ACS Electronic Supporting Info</A></P>

Chemically synthesized PbS Nano particulate thin films for a rapid NO₂ gas sensor

Burungale, Vishal V.,Devan, Rupesh S.,Pawar, Sachin A.,Harale, Namdev S.,Patil, Vithoba L.,Rao, V. K.,Ma, Yuan-Ron,Eun Ae, Jo,Kim, Jin H.,Patil, Pramod S. De Gruyter 2016 MATERIALS SCIENCE -WROCLAW- Vol.34 No.1

<P><B>Abstract</B></P><P>Rapid NO<SUB>2</SUB>gas sensor has been developed based on PbS nanoparticulate thin films synthesized by Successive Ionic Layer Adsorption and Reaction (SILAR) method at different precursor concentrations. The structural and morphological properties were investigated by means of X-ray diffraction and field emission scanning electron microscope. NO<SUB>2</SUB>gas sensing properties of PbS thin films deposited at different concentrations were tested. PbS film with 0.25 M precursor concentration showed the highest sensitivity. In order to optimize the operating temperature, the sensitivity of the sensor to 50 ppm NO<SUB>2</SUB>gas was measured at different operating temperatures, from 50 to 200<SUP>°</SUP>C. The gas sensitivity increased with an increase in operating temperature and achieved the maximum value at 150<SUP>°</SUP>C, followed by a decrease in sensitivity with further increase of the operating temperature. The sensitivity was about 35 % for 50 ppm NO<SUB>2</SUB>at 150<SUP>°</SUP>C with rapid response time of 6 s. T90 and T10 recovery time was 97 s at this gas concentration.</P>

Antifertility Effect of Neem (Azadrichta indica) Seed Kernel Meal in Chickens

Mohan, J.,Tyagi, Praveen K.,Tyagi, Pramod K.,Verma, S.V.S.,Moudgal, R.P. Asian Australasian Association of Animal Productio 1997 Animal Bioscience Vol.10 No.6

The reproductive performance of forty two male broilers divided into three similar groups and fed on isocaloric and isonitrogneous diets containing 0, 10 or 20% water washed neem seed kernel meal (WWNSKM) was investigated from 20 to 32-wks of age. Results on semen characteristics revealed that feeding of WWNSKM led to significant (p < 0.05) reduction in semen volume, sperm concentration associated with increased incidences of morphological abnormalities in the spermatozoa when compared to that of the control birds. A drastic reduction in the fertilizing ability of spermatozoa was observed, the adverse effects being more at higher inclusion level of the cake. Hatchability of eggs also declined in the WWNSKM fed group. Histological examination of testes revealed a higher number of degenerating cells and poor spermatogenesis along with multinucleated giant cells in the seminiferous tubules of the testes of birds receiving the high dose of WWNSKM in diet. It may be concluded that the feeding of WWNSKM by incorporating in isocaloric and isonitrogneous diets to cockerels is associated with adverse effect on their fertility.

Photoluminescence investigation on ultraviolet–emitting Ce³⁺, Mg²⁺-ions-doped/co-doped CaAl₁₂O₁₉ phosphors

Singh, Vijay,Singh, N.,Dubey, Vikas,Singh, Pramod K.,Shinde, K.N.,Ravi Kanth Kumar, V.V. Elsevier 2018 OPTIK -STUTTGART- Vol.158 No.-

<P><B>Abstract</B></P> <P>Ce<SUP>3+</SUP>-doped CaAl<SUB>12</SUB>O<SUB>19</SUB> phosphors with different Ce<SUP>3+</SUP> contents, as well as those with Mg<SUP>2+</SUP> codoped powders, were successfully synthesized using a rapid combustion method (<5 min) for this paper. The powders were well characterized by the X-ray diffraction (XRD) and photoluminescence (PL) techniques. The emission measurements upon a UV-light excitation (262 nm) showed the emission characteristics of the Ce<SUP>3+</SUP> ion that are due to the 5d–4 f transitions. The emission and excitation spectra were recorded as the Ce<SUP>3+</SUP> concentration was kept constant and the Mg<SUP>2+</SUP> concentration was varied. It became evident that the addition of the Mg<SUP>2+</SUP> along with the Ce<SUP>3+</SUP> resulted in increases of the PL intensity, and the reasons for this behavior are discussed.</P>

Tb³⁺ doped Ca₂La₈(SiO₄)₆O₂ oxyapatite phosphors

Singh, Vijay,Singh, N.,Pathak, M.S.,Singh, Pramod K.,Natarajan, V. Elsevier 2018 Optik Vol.171 No.-

<P><B>Abstract</B></P> <P>Tb<SUP>3+</SUP>-doped Ca<SUB>2</SUB>La<SUB>8</SUB>(SiO<SUB>4</SUB>)<SUB>6</SUB>O<SUB>2</SUB> phosphors with different Tb<SUP>3+</SUP> content powders were successfully synthesized using the sol-gel process for this paper. A series of green-emitting Tb<SUP>3+</SUP>-doped Ca<SUB>2</SUB>La<SUB>8</SUB>(SiO<SUB>4</SUB>)<SUB>6</SUB>O<SUB>2</SUB> phosphors was well characterized using the XRD and PL techniques. The emission measurements upon a UV-light excitation of 232 nm showed the Tb<SUP>3+</SUP>-emission characteristics. The emission and excitation spectra were recorded as the Tb<SUP>3+</SUP> concentration was varied. It became evident that the addition of the Tb<SUP>3+</SUP> increased the PL intensity, and the reasons for this behavior are discussed.</P>