16135nas a2200313 45000080041000000220014000412450111000552100069001662600009002353000011002444900008002555201507500263653003115338653005615369653002515425653001915450100001915469700002315488700001915511700001715530700001815547700002215565700001815587700002315605700001815628700002315646700002015669856013215689 2020 eng d a0925-838800aElucidating the effect of CaF 2 on structure, biocompatibility and antibacterial properties of S53P4 glass0 aElucidating the effect of CaF 2 on structure biocompatibility an cAUG  a1547040 v8313 a

The present work focuses on the synthesis and structural elucidation of fluoride containing bioactive glasses in the system (in mol%) given by (53.86) SiO2 – (22.65) Na2O – (21.77-x) CaO – (1.72) P2O5 – x CaF2, where, x = 0, 5.44, 10.885 and 16.33. The role of the incorporated fluoride and its distribution within the glass were interpreted and analyzed using Molecular dynamics (MD) simulations and the results were compared with the modified random network (MRN) model. The interpretations from the model have been verified using the MAS-NMR spectroscopy technique. According to this model, fluoride containing bioactive glasses have been proposed to consist of silicate rich network regions and modifier cation – fluoride rich inter-network regions. The interface region was found to consist of non-bridging oxygen species (NBO) and phosphate cations which are either isolated orthophosphates (Q0P) or bridged with silicates in the form of pyrophosphate (Q1P) units forming Si–O–P bonds. The gradual substitution of CaF2 for CaO in the base glass resulted in an increase in the silicate network connectivity with a reduction in the NBOs and lead to an increase in the association of modifier cations with fluoride ions. However, fluoride ions were found to show a marginal preference to associate with Na+ cations leading to a decrease in the association of Na+ ions with orthophosphate and silicate units. These overall structural findings were correlated with the in vitro ion dissolution behaviour of the bioactive glasses as well as with the thermal properties. The glasses were tested for their in vitro cell viability towards mouse osteoblast type (MC3T3) cells in which fluoride containing bioactive glasses did not show any toxicity and exhibited better cell proliferation. The antibacterial efficacy of the fluoride containing glasses was tested at various concentrations (5, 10 and 20 mg/ml) in E.coli bacterial inoculum in which bactericidal action was evidenced.

10aFluoride bioactive glasses10aIn vitro apatite formation and bactericidal action10aMAS-NMR spectroscopy10aMD simulations1 aPrasad, Sakthi1 aGanisetti, Sudheer1 aJana, Anuradha1 aKant, Shashi1 aSinha, P., K.1 aTripathy, Sucheta1 aIllath, Kavya1 aAjithkumar, T., G.1 aAnnapurna, K.1 aAllu, Amarnath, R.1 aBiswas, Kaushik uhttps://library.ncl.res.in/content/elucidating-effect-caf-2-structure-biocompatibility-and-antibacterial-properties-s53p4-glass00890nas a2200253 4500008004100000022001400041245013400055210006900189260000800258300001100266490000800277100001900285700002300304700001900327700001700346700001800363700002200381700001800403700002300421700001800444700002300462700002000485856013100505 2021 eng d a0925-838800aElucidating the effect of CaF2 on structure, biocompatibility and antibacterial properties of S53P4 glass (vol 831, 154704, 2020)0 aElucidating the effect of CaF2 on structure biocompatibility and cNOV a1612530 v8831 aPrasad, Sakthi1 aGanisetti, Sudheer1 aJana, Anuradha1 aKant, Shashi1 aSinha, P., K.1 aTripathy, Sucheta1 aIllath, Kavya1 aAjithkumar, T., G.1 aAnnapurna, K.1 aAllu, Amarnath, R.1 aBiswas, Kaushik uhttps://library.ncl.res.in/content/elucidating-effect-caf2-structure-biocompatibility-and-antibacterial-properties-s53p4-glass02882nas a2200265 4500008004100000022001400041245008500055210006900140260000900209300001600218490000700234520201500241100002302256700002302279700001802302700002002320700001802340700003202358700002302390700001802413700002102431700002702452700002302479856011402502 2021 eng d a0020-166900aIonic conductivity of Na3Al2P3O12 glass electrolytes role of charge compensators0 aIonic conductivity of Na3Al2P3O12 glass electrolytes role of cha cSEP  a12893-129050 v603 aIn glasses, a sodium ion (Na+) is a significant mobile cation that takes up a dual role, that is, as a charge compensator and also as a network modifier. As a network modifier, Na+ cations modify the structural distributions and create nonbridging oxygens. As a charge compensator, Na+ cations provide imbalanced charge for oxygen that is linked between two network-forming tetrahedra. However, the factors controlling the mobility of Na+ ions in glasses, which in turn affects the ionic conductivity, remain unclear. In the current work, using high-fidelity experiments and atomistic simulations, we demonstrate that the ionic conductivity of the Na3Al2P3O12 (Si0) glass material is dependent not only on the concentration of Na+ charge carriers but also on the number of charge-compensated oxygens within its first coordination sphere. To investigate, we chose a series of glasses formulated by the substitution of Si for P in Si0 glass based on the hypothesis that Si substitution in the presence of Na+ cations increases the number of SiOAl bonds, which enhances the role of Na as a charge compensator. The structural and conductivity properties of bulk glass materials are evaluated by molecular dynamics (MD) simulations, magic angle spinning-nuclear magnetic resonance, Raman spectroscopy, and impedance spectroscopy. We observe that the increasing number of charge-imbalanced bridging oxygens (BOs) with the substitution of Si for P in Si0 glass enhances the ionic conductivity by an order of magnitudefrom 3.7 x 10(-8) S.cm(-1) to 3.3 x 10(7) S.cm(-1) at 100 degrees C. By rigorously quantifying the channel regions in the glass structure, using MD simulations, we demonstrate that the enhanced ionic conductivity can be attributed to the increased connectivity of Na-rich channels because of the increased charge-compensated BOs around the Na atoms. Overall, this study provides new insights for designing next-generation glass-based electrolytes with superior ionic conductivity for Na-ion batteries1 aKeshri, Shweta, R.1 aGanisetti, Sudheer1 aKumar, Rajesh1 aGaddam, Anuraag1 aIllath, Kavya1 aAjithkumar, Thalasseril, G.1 aBalaji, Sathravada1 aAnnapurna, K.1 aNasani, Narendar1 aKrishnan, N., M. Anoop1 aAllu, Amarnath, R. uhttps://library.ncl.res.in/content/ionic-conductivity-na3al2p3o12-glass-electrolytes-role-charge-compensators03045nas a2200325 4500008004100000022001400041245015900055210006900214260000900283300001100292490000800303520193300311653001402244653001702258653002302275653001902298653002402317100002302341700002202364700002302386700002502409700001802434700002002452700001902472700003202491700002502523700002702548700002302575856012102598 2022 eng d a1359-645400aElucidating the influence of structure and Ag+ -Na+ ion-exchange on crack-resistance and ionic conductivity of Na3Al1.8Si1.65 P-1.8 O-12 glass electrolyte0 aElucidating the influence of structure and Ag Na ionexchange on  cAPR  a1177450 v2273 a

Glasses are emerging as promising and efficient solid electrolytes for all-solid-state sodium-ion batteries. However, they still suffer from poor ionic conductivity and crack-resistance, which need to be improved for better battery performance, reliability, and service life. The current study shows a significant enhancement in crack resistance (from 11.3 N to 32.9 N) for Na3Al (1.8) Si-1.65 P1.8O12 glass (Ag-0 glass) upon Na+ -Ag+ ion-exchange (IE) due to compressive stresses generated in the glass surface while the ionic conductivity values (similar to 10(-5) S/cm at 473 K) were retained. In this study, magic angle spinning-nuclear magnetic resonance (MAS-NMR), molecular dynamics (MD) simulations, Vickers micro hardness, and impedance spectroscopic techniques were used to evaluate the intermediate-range structure, atomic structure, crack resistance and conductivity of the glass. MAS-NMR and MD simulations confirm the presence of Si-OAl-O-P groups in the glass, thus enabling formation of Na percolated channel regions. AC-conductivity analysis for Ag-0 and ion-exchanged Ag-0 glass suggests that the mobility of Na+ ion increases with increasing temperature. It is observed that the measured mean square displacement (root < R-2(t(p))>) for sodium cations using AC-conductivity isotherms is nearly constant up to 448 K and then increases with increasing temperature up to 523 K. From the impedance spectra for ion-exchanged Ag-0 glass, it is identified that the increase in root < R-2 (t(nu))> and thereby, the mobility of sodium-ions for Ag-0 glass is due to the structural variations in the Ag-0 glass with increasing the temperature. Overall, the mechanisms presented in this article helps in formulating better glass based electrolyte materials for room temperature or high temperature sodium-ion batteries. (C) 2022 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

10aamorphous10aIon-exchange10aIonic-conductivity10aMD simulations10aMechanical property1 aKeshri, Shweta, R.1 aMandal, Indrajeet1 aGanisetti, Sudheer1 aKasimuthumaniyan, S.1 aKumar, Rajesh1 aGaddam, Anuraag1 aShelke, Ankita1 aAjithkumar, Thalasseril, G.1 aGosvami, Nitya, Nand1 aKrishnan, N., M. Anoop1 aAllu, Amarnath, R. uhttps://library.ncl.res.in/content/elucidating-influence-structure-and-ag-na-ion-exchange-crack-resistance-and-ionic