Dr. D. PARADESI
@SRM IST
Assistant Professor
CHEMISTRY
EDUCATION
M.Sc PhD
RESEARCH INTERESTS
POLYMER CHEMISTRY-ELECTROCHEMISTRY-ANALYTICAL CHEMISTRY
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Siva Moorthy, Berlina Maria Mahimai, Dinakaran Kannaiyan, and Paradesi Deivanayagam
Elsevier BV
Theerthagiri Senthil, Ayyavu Chandramohan, Ponnusamy Senthil Kumar, Deivanayagam Paradesi, and Kannaiyan Dinakaran
American Chemical Society (ACS)
Berlina Maria Mahimai, Siva Moorthy, Gandhimathi Sivasubramanian, and Paradesi Deivanayagam
American Chemical Society (ACS)
Siva Moorthy, Gandhimathi Sivasubramanian, Dinakaran Kannaiyan, and Paradesi Deivanayagam
Elsevier BV
Anie Shejoe Justin Jose Sheela, Siva Moorthy, Berlina Maria Mahimai, Karthikeyan Sekar, Dinakaran Kannaiyan, and Paradesi Deivanayagam
American Chemical Society (ACS)
This research work focuses on developing a robust polymer electrolyte membrane (PEM) with high proton efficiency toward proton exchange membrane fuel cells (PEMFCs). In this study, poly ether sulfone (PES) was sulfonated by chlorosulfonic acid to yield sulfonated poly ether sulfone (SPES) followed by incorporation with bismuth-based additives such as bismuth trimesic acid (BiTMA) and bismuth molybdenum oxide (Bi2MoO6). The composite membrane was thoroughly investigated for its structural and physicochemical properties such as FT-IR, SEM, TGA, contact angle, water uptake, oxidative stability, ion-exchange capacity, and swelling ratio. Incorporation of additives into the polymer was confirmed by XPS and XRD analysis. The proton conductance of the pristine SPES is 4.19 × 10–3 S cm–1, whereas that of the composite membrane SPES/BiTMA-10 is 10 × 10–3 S cm–1 and that of SPES/Bi2MoO6-15 is 7.314 × 10–3 S cm–1; both the composite membranes exhibit higher proton conductivity than the pristine SPES membrane. The physicochemical characteristics and impedance measurements of the electrolyte reported can be viable to the PEM membrane.
Senthil Theerthagiri, Srinivasan Krishnan, Paradesi Deivanayagam, Chandran Muthiah, and Dinakaran Kannaiyan
Wiley
Theerthagiri Senthil, Peethambaram Prabukanthan, Deivanayagam Paradesi, and Kannaiyan Dinakaran
Wiley
Mahalingam Aparna, Pushparaj Hemalatha, Deivanayagam Paradesi, and David Akash Raj
Wiley
Siva Moorthy and Paradesi Deivanayagam
American Chemical Society (ACS)
New strategies for enhancement of the fuel-cell performance of a poly(2,5-benzimidazole) (ABPBI) membrane loaded with a functionalized cobalt-based metal-organic framework (MOF) for H2-O2 fuel cells. ABPBI was prepared using the polycondensation method, and various proportions of sulfonated cobalt MOF (sCo-MOF) were incorporated into ABPBI to fabricate a proton-exchange membrane (PEM). Later, the fabricated membranes were soaked in 1 M sulfuric acid to produce sulfonated PEMs. The developed composite membranes had increased proton conductivity, tensile strength, physicochemical properties, and fuel-cell performance compared to the sulfonated ABPBI (sABPBI) membrane. A membrane embedded with 4 wt % sCo-MOF shows higher water uptake and ion-exchange capacity values of 23.25% and 2.89 mequiv g-1, respectively. The membrane electrode assemblies were fabricated to perform unit-cell tests for both sABPBI and 4 wt % sCo-MOF/sABPBI membranes. The 4 wt % sCo-MOF-loaded sABPBI membrane demonstrated good unit-cell performance in the fuel-cell test, with a power density of 415.8 mW cm-2 at 80 °C, superior to the pristine sABPBI membrane's power density of 178.6 mW cm-2.
R. Gomathi and D. Paradesi
Elsevier BV
Praveen Thangamuthu, Siva Moorthy, Berlina Maria Mahimai, Dinakaran Kannaiyan, and Paradesi Deivanayagam
Informa UK Limited
Abstract Organic-inorganic sulfonated poly(ether sulfone) (SPES)-bismuth oxide (Bi2O3) composite membranes were prepared by the facile solution casting method. Poly(ether sulfone) (PES) polymer was sulfonated using concentrated sulfuric acid as a sulfonating agent and the degree of sulfonation was found to be 42.6%. Structural analysis of prepared samples was characterized using FT-IR, proton NMR, XRD, GPC, SEM and XPS. Physicochemical properties like water uptake, ion exchange capability, thermal properties and proton conductivity of pristine and composite membranes were analyzed. The ion-exchange capacity of the prepared electrolyte membranes was found in the range between 1.5 and 2.4 meq g−1. SPES composite membrane loaded with 6 wt.% Bi2O3 displayed the highest ionic conductivity of 0.045 S cm−1 than the pristine membrane (0.023 S cm−1). The overall results validate that the impregnation of Bi2O3 into SPES polymer exhibits good performance over the neat membrane. This research demonstrates that SPES/Bi2O3 composite membranes are viable electrolytes for fuel cell practice. Graphical Abstract
Mahalingam Aparna, Deivanayagam Paradesi, and Pushparaj Hemalatha
Springer Science and Business Media LLC
Poonkuzhali Kulasekaran, Siva Moorthy, Paradesi Deivanayagam, Karthikeyan Sekar, and Hemalatha Pushparaj
Royal Society of Chemistry (RSC)
Novel proton exchange membranes consisting of sulfonated polystyrene ethylene butylene polystyrene (sPSEBPS), sulfonated poly ether sulfone (SPES) and hexagonal boron nitride (hBN) were fabricated using a facile solution casting technique.
Poonkuzhali Kulasekaran, Berlina Maria Mahimai, Gandhimathi Sivasubramanian, Hemalatha Pushparaj, and Paradesi Deivanayagam
Wiley
Berlina Maria Mahimai, Gandhimathi Sivasubramanian, Karthikeyan Sekar, Dinakaran Kannaiyan, and Paradesi Deivanayagam
Royal Society of Chemistry (RSC)
Fuel cell technology yields cleaner energy resources for diverse applications such as transport, power stationery, and portable devices.
Berlina Maria Mahimai, Gandhimathi Sivasubramanian, Siva Moorthy, and Paradesi Deivanayagam
American Chemical Society (ACS)
Gandhimathi Sivasubramanian, Senthil Andavan Gurusamy Thangavelu, Berlina Maria Mahimai, Krishnan Hariharasubramanian, and Paradesi Deivanayagam
Springer Science and Business Media LLC
Poonkuzhali Kulasekaran, Berlina Maria Mahimai, and Paradesi Deivanayagam
Informa UK Limited
ABSTRACT Novel ternary proton exchange membranes composed of sulfonated polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene (sPSEBPS), graphene oxide (GO) and ammonium ionic liquid (AIL) were prepared by a facile solution casting technique. The incorporation of GO and AIL into the sPSEBPS polymer matrix enhances the thermal stability and the ionic conductivity of the composites. The ion-exchange capacity of the membranes was found in the range between 0.281 and 1.248 meq. g−1. The sPSEBPS/GO/AIL-20 composite membrane showed a proton conductivity of 0.0353 S. cm−1 at 30 °C. The outcome of the results projected that the prepared polymer composite membranes are viable candidates for fuel cell applications. Graphical abstract
Berlina Maria Mahimai, Poonkuzhali Kulasekaran, and Paradesi Deivanayagam
Wiley
Berlina Maria Mahimai, Gandhimathi Sivasubramanian, Poonkuzhali Kulasekaran, and Paradesi Deivanayagam
Royal Society of Chemistry (RSC)
New series of polymer composites were prepared from sulfonated polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene and CuO loaded in graphitic carbon nitride embedded with an ionic liquid 2,4,6-triphenylpyrylium tetrafluoroborate.
Rajagopal Gomathi, Harindran Suhana, and Deivanayagam Paradesi
Wiley
Krishnan Suresh Babu and Deivanayagam Paradesi
Springer Science and Business Media LLC
A new reversed-phase high-performance liquid chromatography (RP-HPLC) method has been developed for the separation and identification of impurities present in metadoxine. Herein, we report that one of the impurities eluted from the metadoxine sample is 4-deoxypyridoxine hydrochloride (4-DPH). In HPLC analysis, the retention time (RT) of 4-DPH was observed to be at 13.5 min in both the reference and metadoxine samples and the relative retention time (RRT) was 1.71. The presence of 4-DPH in a metadoxine sample was also confirmed by a chromatogram obtained by spiking the 4-DPH standard into the sample. Furthermore, the elution and mass of impurity 4-DPH in metadoxine was proven by LC-mass spectroscopy studies. This method highlights the presence of another unknown impurity that has so far not been observed in earlier methods of metadoxine evaluation. Hence, the developed method achieved superior resolution between metadoxine and impurities and thereby facilitates the production of a purer metadoxine drug.
Gugan Punniakotti, Gandhimathi Sivasubramanian, Senthil Andavan Gurusamy Thangavelu, and Paradesi Deivanayagam
Informa UK Limited
ABSTRACT Polymer composite membranes composed of crosslinked sulfonated poly(vinyl alcohol) (SPVA) and fly ash (FA) were prepared via solution casting method. The physicochemical properties of these electrolyte membranes were studied in detail. SEM and XRD results provide evidence for the successful incorporation of fly ash into the SPVA matrix. As such SPVA polymer loaded with 20 wt.% of fly ash exhibited the ionic conductivity of 0.016 S. cm−1, whereas pristine membrane occurred to show 0.008 S. cm−1. The substantial results achieved with the organic-inorganic composites have been demonstrated and reported membranes can be a feasible electrolyte for fuel cell applications. Graphical abstract
Berlina Maria Mahimai, Poonkuzhali Kulasekaran, Gandhimathi Sivasubramanian, and Paradesi Deivanayagam
Informa UK Limited
ABSTRACT Polymer nanocomposite membranes based on sulfonated poly (ether ether ketone) (SPEEK) and barium strontium titanium oxide (BSTO) have been prepared by solution casting technique. The SPEEK was obtained by direct sulfonation of poly (ether ether ketone) using concentrated sulfuric acid. The degree of sulfonation of SPEEK was determined by 1H NMR spectroscopy. The composite membranes showed higher water uptake capacity when compared to SPEEK. The ion-exchange capacity of the composite membranes was found in the range between 1.48 and 1.62 meq. g−1. The thermal stability of composite membrane was found to be good enough to use in fuel cell. GRAPHICAL ABSTRACT
Murali Prathap, Kulasekaran Poonkuzhali, Maria Mahimai Berlina, Pushparaj Hemalatha, and Deivanayagam Paradesi
SAGE Publications
A new series of polymer composite membranes was fabricated using a linear sulfonated poly(ether ether ketone) (SPEEK) polymer with zinc cobalt oxide (ZCO) as an inorganic filler and evaluated for fuel cell applications. SPEEK was obtained by the direct sulfonation of PEEK using concentrated sulfuric acid, and appropriate quantities of ZCO were loaded into it to yield the polymer composites. Proton nuclear magnetic resonance studies revealed the degree of sulfonation of SPEEK to be 55%, while morphological studies confirmed the successful incorporation of inorganic fillers into the polymer matrix. To evaluate the suitability of the prepared composite membranes for fuel cell applications, their physicochemical properties were studied in detail. The pristine SPEEK membrane exhibited a proton conductivity of 0.009 S cm−1 at 30°C, whereas the values for the composite membranes loaded with 2.5 to 10 wt% of ZCO were in the range 0.012–0.020 S cm−1. Moreover, the composite membranes showed excellent thermal stability up to 370°C. Indeed, the membranes obtained by the incorporation of ZCO into the SPEEK polymer show potential for fuel cell applications.