Estimation of Excited State Dipole Moment of Exalite Dyes by Solvatochromic Shift Studies

Inamdar, S. R.,Nadaf, Y.F.,Deshpande, D.K.,Karguppikar, A.M. Korean Society of Photoscience 2002 Journal of Photosciences Vol.9 No.1

The solvent effect in a series of polar and non-polar solvents of varying dielectric constants and refractive indices has been investigated by studying electronic spectra (S$_1$band) of a series of exalite laser dyes at room temperature (25$\pm$1$\^{C}$). These data are used to determine the magnitude ($\mu$$\_$e/) and direction ($\theta$) of the electric dipole moments in the first electronically excited state. The results indicate that the observed band systems in these compounds may be attributed to ←$\pi$ transition.

Optical properties in Mn-doped ZnS thin films: Photoluminescence quenching

Inamdar, A.I.,Cho, S.,Jo, Y.,Kim, J.,Han, J.,Pawar, S.M.,Woo, H.,Kalubarme, R.S.,Park, C.,Kim, H.,Im, H. North-Holland 2016 Materials letters Vol.163 No.-

Mn-doped ZnS thin films are synthesized on soda-lime glass substrates using magnetron co-sputtering technique. X-ray diffraction and atomic force microscopy measurements indicate that of the as-obtained films including the highest Mn (~11% relative to the Zn concentration) in the lattice of ZnS are amorphous with a granular morphology. X-ray photoelectron spectroscopy reveals the presence of Zn<SUP>2+</SUP>, Mn<SUP>2+</SUP> and S<SUP>2-</SUP> chemical states in the films. The undoped ZnS film exhibits photoluminescence (PL) peaks at energies around 3.26eV (wavelength ~379nm) and 2.95eV (~420nm), which originate from the interplay between excited electron, defect (sulfur vacancy) states and the valence band. For the Mn-doped ZnS films, the band-to-band emission peak is quenched and shifts toward to higher energies at a rate of 11.7+/-2meV/Mn%. We propose that Mn dopant-mediated structural phases and non-radiative deep traps in ZnS cause the modification in the optical transition.

Highly efficient electro-optically tunable smart-supercapacitors using an oxygen-excess nanograin tungsten oxide thin film

Inamdar, Akbar I.,Kim, Jongmin,Jo, Yongcheol,Woo, Hyeonseok,Cho, Sangeun,Pawar, Sambhaji M.,Lee, Seongwoo,Gunjakar, Jayavant L.,Cho, Yuljae,Hou, Bo,Cha, SeungNam,Kwak, Jungwon,Park, Youngsin,Kim, Hyun North-Holland 2017 Solar Energy Materials and Solar Cells Vol. No.

<P><B>Abstract</B></P> <P>A smart supercapacitor shares the same electrochemical processes as a conventional energy storage device while also having electrochromic functionality. The smart supercapacitor device can sense the energy storage level, which it displays in a visually discernible manner, providing increased convenience in everyday applications. Here, we report an electro-optically tunable smart supercapacitor based on an oxygen-rich nanograin WO<SUB>3</SUB> electrode. The nanostructured WO<SUB>3</SUB> electrode is dark blue in color in the charged state and becomes transparent in its discharged state with a high optical modulation of 82%. The supercapacitor has a specific capacitance of 228Fg<SUP>−1</SUP> at 0.25 Ag<SUP>−1</SUP> with a large potential window (1.4V). It is highly durable, exhibits good electrochemical stability over 2000 cycles, retains 75% of its initial capacitance, and exhibits high coloration efficiency (~170cm<SUP>2</SUP>/C). The excellent electrochromic and electrochemical supercapacitor properties of the electrode is due to the synergetic effect between nanograin morphology and excess oxygen. A smart-supercapacitor fabricated with an oxygen-rich nanograin WO<SUB>3</SUB> electrode exhibits a superb combination of energy storage and highly-efficient electrochromic features in one device that can monitor the energy storage level through visible changes in color.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Oxygen-excess nanograin WO<SUB>3+δ</SUB> is synthesized for a smart supercapacitor electrode. </LI> <LI> It is dark blue in the charged state and transparent in the discharged state with an optical modulation of 82%. </LI> <LI> The device exhibits an excellent coloration efficiency of ~170cm<SUP>2</SUP>/C. </LI> <LI> The specific capacity is 228Fg<SUP>−1</SUP> with a large potential window of 1.4V. </LI> </UL> </P>

아욱과의 절간 (節間) 도관절 (導管節)

Inamdar J . A .,R . Balakrishna Bhat,T . V . Ramana Rao 한국식물학회 1983 Journal of Plant Biology Vol.26 No.1

Internodal vessel elements are studied in 20 genera, 75 species and 33 cultivars of Hibiscus rosa-sinensis beloning to the Malvaceae. The minimum and maximum length and diameter range from 79∼466 and 14∼88㎛, respectively. The vessel elements are either cylindrical, fusiform, conical, clavate, oval, column-, drum-, fish and cup-like or erratic. Perforation plates are exclusively simple in all the species investigated, except occasionally scalariform in varieties of Hibiscus roas-sinensis. In most of the species studied vessel elements have predominantly two perforation plates or occasionally one and three. Adjacent side wall thichening is commonly simple and border pitted, mixed, scalariform, helical and reticulate. The vessel elements vary in their size, shape, number and inclination of perforation plates and adjacent wall thichening.

Mesoporous Ni-PANI composite electrode for electrochromic energy storage applications

Inamdar, Akbar I.,Chavan, Harish S.,Kim, Hyungsang,Im, Hyunsik Elsevier 2019 Solar energy materials and solar cells Vol.201 No.-

<P><B>Abstract</B></P> <P>Nanostructured mesoporous Ni-PANI thin film electrodes are fabricated on indium-doped tin oxide (ITO) conducting glass substrates using a pulse potential electro-polymerization technique. The Ni-PANI film is amorphous in nature and exhibits a mesoporous cauliflower like morphology. The multifunctional characteristics of Ni-PANI as an electrode for a smart supercapacitor are investigated using electrochemical and optical techniques in 0.5 M LiClO<SUB>4</SUB> +PC electrolyte. It is dark blue when it is charged at 0.7 V (vs SCE), and it is transparent when it is discharged at −0.7 V (vs SCE). Moreover, it can exhibit other colours like sky blue and parrot green in intermediate states. Specific discharge capacitance of 543 Fg<SUP>−1</SUP> and 267 Fg<SUP>−1</SUP> at a current density of 1 Ag<SUP>−1</SUP> is obtained for Ni-PANI and pure PANI respectively. The observed colouration efficiency is 45.9 cm<SUP>2</SUP>C<SUP>−1</SUP> for Ni-PANI and 35.1 cm<SUP>2</SUP>C<SUP>−1</SUP> for pure PANI at a wavelength of 630 nm. An outstanding optical modulation of 55.6% with a capacity retention of 90% after 5000 cycles is obtained for Ni-PANI electrode. The robust synthesis of Ni-PANI electrodes with efficient smart supercapacitor activity can be used as alternative materials in smart energy storage devices.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The NiO<SUB>x</SUB>-PANI exhibited multifunctional activity as energy storage and electrochromism. </LI> <LI> It is capable of sensing colour with respect to the level of energy stored. </LI> <LI> The device exhibits a colouration efficiency of 45.9 cm<SUP>2</SUP>C<SUP>-1</SUP> with an optical modulation of 55.6%. </LI> <LI> The high specific capacity is 543 F g<SUP>−1</SUP>, with a large potential window of 1.3 V. </LI> </UL> </P>

Nickel titanate lithium-ion battery anodes with high reversible capacity and high-rate long-cycle life performance

Inamdar, A.,Kalubarme, R.,Kim, J.,Jo, Y.,Woo, H.,Cho, S.,Pawar, S. M.,Park, C. J.,Lee, Y. W.,Sohn, J. Royal Society of Chemistry 2016 Journal of materials chemistry. A, Materials for e Vol.4 No.13

<P>We demonstrate the impressive performance of sparsely studied nickel titanate anode materials for Li-ion batteries (LIBs). The nickel titanate anode delivers a high reversible discharge capacity of 435 mA h g(-1) at a current density of 35 mA g(-1), high-rate performance and excellent cycling retention of 96% with a long-term cycling stability at 1500 mA g(-1) over 300 cycles. The coulombic efficiency is obtained as high as 98%. This superior nickel titanate electrode material could be used as a safe, low-cost, long cycle life anode material for next-generation LIBs with a high power capability.</P>

Synthesis and enhanced electrochemical supercapacitive properties of manganese oxide nanoflake electrodes

Inamdar, A.I.,Jo, Y.,Kim, J.,Han, J.,Pawar, S.M.,Kalubarme, R.S.,Park, C.J.,Hong, J.P.,Park, Y.S.,Jung, W.,Kim, H.,Im, Hyunsik Elsevier 2015 ENERGY Vol.83 No.-

<P><B>Abstract</B></P> <P>MnO<SUB>2+δ</SUB> (Manganese oxide) nanoflakes were synthesized for use as electrode material in electrochemical supercapacitors. The nanoflakes were produced via RF-magnetron sputtering with various excess oxygen contents (δ), and the electrochemical supercapacitive properties of the MnO<SUB>2+δ</SUB> nanoflakes were investigated as a function of δ with the use of a Na<SUB>2</SUB>SO<SUB>4</SUB> electrolyte. The excess oxygen (δ) induces the MnO<SUB>2+δ</SUB> nanoflakes to form a thin open structure, and μ-Raman measurements revealed that the MnO<SUB>2+δ</SUB> nanoflakes formed a birnessite phase with a layered structure. X-ray photoelectron spectroscopy was used to obtain quantitative information on both the oxidation state and the chemical composition of the nanoflake electrodes. The crystallinity of the nanoflakes improved when the oxygen partial pressure increased during sputtering. At an optimal δ ∼ 0.6, the electrochemical stability and the capacity retention significantly improved, and electrochemical impedance spectroscopy revealed that easy access of Na<SUP>+</SUP> ions into the nanoflakes at an optimal δ value resulted in a low diffusion resistance, playing a key role in determining the improvement in the supercapacitor characteristics.</P> <P><B>Highlights</B></P> <P> <UL> <LI> MnO<SUB>2+δ</SUB> nanoflakes are grown using RF-magnetron sputtering. </LI> <LI> Excess oxygen (δ) endorses the formation of a porous and open structure. </LI> <LI> At δ ∼ 0.6, the stability and capacity retention are significantly improved. </LI> <LI> Low diffusion resistance plays a key role in determining supercapacitor characteristics. </LI> </UL> </P>

Nanograin tungsten oxide with excess oxygen as a highly reversible anode material for high-performance Li-ion batteries

Inamdar, Akbar I.,Chavan, Harish.S.,Ahmed, Abu Talha Aqueel,Cho, Sangeun,Kim, Jongmin,Jo, Yongcheol,Pawar, Sambhaji M.,Park, Youngsin,Kim, Hyungsang,Im, Hyunsik North-Holland 2018 Materials Letters Vol. No.

<P><B>Abstract</B></P> <P>Nanogranular tungsten oxide (WO<SUB>3</SUB>) with excess oxygen is synthesized and its battery performance is evaluated as an anode material for the Li-ion battery (LIB). The formation of a monoclinic WO<SUB>3</SUB> phase is confirmed using X-ray diffraction (XRD) and micro (µ)-Raman spectroscopy analyses. The Rutherford back scattering results confirm the existence of excess oxygen in the film. The charge discharge processes are associated with the conversion of the WO<SUB>3</SUB> from the oxide state to the metallic state, and vice versa, and it shows a maximum specific capacity of 778.8 mAh g<SUP>−1</SUP> at a current density of 0.1 Ag<SUP>−1</SUP> in the first discharge. Even at a very high current density of 1 Ag<SUP>−1</SUP>, the sample retains the capacity of 228.6 mAh g<SUP>−1</SUP>. It shows excellent rate capability and a long-term cycling stability over 500 charge–discharge cycles, with capacity retention of 217%. The observed high discharge capacity and superior long-term cyclability of the nanograin WO<SUB>3</SUB> anode are attributable to the synergetic effect of the excess-oxygen induced increased donor density and enhanced electrical conductivity.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Nanogranular WO<SUB>3</SUB> with excess oxygen is synthesized as an anode material for LIB. </LI> <LI> A maximum specific capacity of ∼779 mAh g<SUP>−1</SUP> and excellent rate capability are observed. </LI> <LI> Long-term cycling stability over 500 charge–discharge cycles with high capacity retention of 217% is obtained. </LI> <LI> Capacity retention of ∼229 mAh g<SUP>−1</SUP> at a very high current density of 1 Ag<SUP>−1</SUP> is achieved. </LI> </UL> </P>

Influence of operating temperature on Li₂ZnTi₃O₈ anode performance and high-rate charging activity of Li-ion battery

Inamdar, Akbar I.,Ahmed, Abu Talha Aqueel,Chavan, Harish S.,Jo, Yongcheol,Cho, Sangeun,Kim, Jongmin,Pawar, Sambhaji M.,Hou, Bo,Cha, SeungNam,Kim, Hyungsang,Im, Hyunsik Elsevier 2018 CERAMICS INTERNATIONAL Vol.44 No.15

<P><B>Abstract</B></P> <P>The temperature-dependent performance of a Li<SUB>2</SUB>ZnTi<SUB>3</SUB>O<SUB>8</SUB> (LZTO) anode and the ultrafast-charging activity of a Li-ion battery were investigated. The LZTO anode operates at different temperatures between − 5 and 55 °C and in this work its sustainability is discussed in terms of storage performance. It delivered a discharge capacity of 181.3 mA h g<SUP>−1</SUP> at 25 °C, which increased to 227.3 mA h g<SUP>−1</SUP> at 40 °C and 131.2 mA h g<SUP>−1</SUP> at − 5 °C. The variation in the discharge capacity with temperature is associated with the reaction kinetics and the change in internal resistance. It showed a capacity retention of 64% and a coulombic efficiency of 98% over 500 cycles. Exhibiting a discharge capacity of 107 mA h g<SUP>−1</SUP>, the LZTO anode was sustainable over 100 charge-discharge cycles at an ultra-high charging rate of 10 Ag<SUP>−1</SUP>. The reaction kinetics estimated from a cyclic voltammetry analysis at high scan rates revealed a capacitive-type storage mechanism.</P> <P><B>Graphical abstract</B></P> <P>We developed an ultrafast rechargeable Li<SUB>2</SUB>ZnTi<SUB>3</SUB>O<SUB>8</SUB> (LZTO) anode for lithium-ion batteries. A half-cell LZTO battery delivered the highest reversible first discharge capacity of 181.3 mA h g<SUP>−1</SUP> at a current rate of 0.1 Ag<SUP>−1</SUP> and the maximum capacity of 106.97 mA h g<SUP>−1</SUP> was obtained when charged at an ultrafast charging rate of 10.0 Ag<SUP>−1</SUP>. The LZTO showed an excellent capacity-retention of 106.28%, suggesting excellent electrode sustainability, even at ultra-high-charging rates.</P> <P>[DISPLAY OMISSION]</P>

Memory Conductance Switching in a Ni-Ti-O Compound Thin Film

Inamdar, Akbar I.,Kim, Jongmin,Jang, Byeonguk,Kim, Duhwan,Im, Hyunsik,Jung, Woong,Kim, Hyungsang IOP Publishing 2012 Japanese journal of applied physics Vol.51 No.r10