Confinement of Ag₃PO₄ nanoparticles supported by surface plasmon resonance of Ag in glass: Efficient nanoscale photocatalyst for solar H₂ production from waste H₂S

Patil, S.S.,Patil, D.R.,Apte, S.K.,Kulkarni, M.V.,Ambekar, J.D.,Park, C.J.,Gosavi, S.W.,Kolekar, S.S.,Kale, B.B. Elsevier 2016 Applied Catalysis B Vol.190 No.-

<P>Ag3PO4 is a good photocatalyst but ubiquitously known for its photocorrosion problem during photocatalytic reaction. Therefore, stabilization of Ag3PO4 with retaining its fundamental properties has immense importance. With this motivation, we designed Ag3PO4 glass nanocomposite to resolve the problem of photocorrosion. Moreover, the effect of size quantization on photocatalytic activity has also been demonstrated by growing the cubic Ag3PO4 nanoparticles with size in the range of 3-9 nm in glass matrix via melt and quenching method. The band gap of Ag3PO4 has been tuned (2.56-2.25 eV) in glass matrix with respect to size. Considering the size tunable band gap of Ag3PO4 glass nanocomposite within visible region, it is demonstrated as a photocatalyst for hydrogen (H-2) production from copious hazardous waste H2S. The utmost H-2 production i.e. 3920.4 mu mol h(-1) g(-1) is obtained using 1 gm of Ag3PO4 glass nanocomposite powder. The apparent quantum yield for H-2 production is calculated to be 5.51% for Ag3PO4 glass nanocomposite. Interestingly, presence of plasmonic Ag was also observed in Ag3PO4 glass nanocomposite which contributes for H-2 production through enhanced light absorption, efficient charge separation and improved stability. Recycling study of sample reveals stable H-2 production efficiency and good stability of the photocatalyst. Surprisingly, catalyst can be reused many times and recovery of catalyst is possible just rinsing with distilled water. All these results demonstrate directly the feasibility of designing a new generation photocatalysts. (C) 2016 Published by Elsevier B.V.</P>

Green approach for hierarchical nanostructured Ag-ZnO and their photocatalytic performance under sunlight

Patil, S.S.,Mali, M.G.,Tamboli, M.S.,Patil, D.R.,Kulkarni, M.V.,Yoon, H.,Kim, H.,Al-Deyab, S.S.,Yoon, S.S.,Kolekar, S.S.,Kale, B.B. Elsevier Science Publishers 2016 CATALYSIS TODAY - Vol.260 No.-

<P>In this study, the synthesis of silver-zinc oxide (Ag-ZnO) nanostructures with a plant-extract-mediated hydrothermal method was investigated. The eco-friendly plant extract Azadirachta indica (Neem) was used as a reducing agent. The X-ray diffraction patterns showed the formation of face-centered cubic (fcc) Ag nanoparticles (NPs) and a wurtzite ZnO structure. An optical study of these nanostructures revealed two absorption edges: one at 393 nm corresponding to ZnO and the other at approximately 440 nm corresponding to Ag. A morphology study showed that hierarchical ZnO nanostructures were decorated with 10-50-nm-diameter Ag NPs. The formation and growth mechanism were also examined. A photoelectrochemical study was performed to investigate the electronic interactions between the ZnO and Ag NPs in the photoanode upon exposure to light. The Ag NPs act as electron acceptors, inhibiting electron-hole recombination. The photocatalytic activity of the Ag-ZnO nanostructures was examined by observing the degradation of aqueous methylene blue (MB) dye under natural sunlight. The apparent rate constant determined for the photocatalytic degradation of MB by the Ag-ZnO nanostructures was 5.9668 x 10(-2) min(-1), which was faster than that of the untreated ZnO nanostructures (2.527 x 10(-2) mm(-1)). This plant-extract-mediated synthetic route could also be applied to the synthesis of other Ag-semiconductor oxide nanostructures. (C) 2015 Elsevier B.V. All rights reserved.</P>

Tailor-made dicationic ionic liquid as a fluorescent sensor for detection of hydroquinone and catechol

Patil, Sandip K.,Patil, Suryakant A.,Vadiyar, Madagonda M.,Awale, Deepak V.,Sartape, Ashish S.,Walekar, Laxman S.,Kolekar, Govind B.,Ghorpade, Uma V.,Kim, Jin H.,Kolekar, Sanjay S. Elsevier 2017 Journal of molecular liquids Vol.244 No.-

<P>We are exploring a geminal dicationic ionic liquid (DCIL), 1,1'-(propane-1,3-diyl)bis(4-aminopyridin-1-ium) dihydroxide, [C-3(Amp)(2)][OH](2) as a fluorescent probe for detection of dihydroxybenzenes viz. hydroquinone (HQ) and catechol (CC). Simple and sensitive spectrofluorometric method is described which accomplished with efficient quenching of fluorescence of aqueous DCIL by dihydroxybenzenes. The sensor offers good linear detection range of 1-400 mu M and 1-1000 mu M with detection limits of 0.31 mu M and 0.40 mu M for HQ and CC, respectively. Under alkaline conditions HQ/CC oxidizes to corresponding benzoquinones which interact with DCIL and consequently quenching of fluorescence is occurred. This essential alkaline condition is in situ provided by purposefully tuned DCIL to having basic nature. The plausible quenching mechanism that involves photo-induced charge transfer pathway is evidently discussed. The proposed method is competent over a broad detection range. Selectivity of method is demonstrated by scrutinizing intervention of various interfering species. Recoveries from water sample analysis emphasize the possible use of DCIL probe in the detection of HQ and CC from water sources. The proposed method certainly confers a new approach in sensing techniques for dihydroxybenzenes. (C) 2017 Published by Elsevier B.V.</P>

Periodically ordered inverse opal TiO₂/polyaniline core/shell design for electrochemical energy storage applications

Patil, B.H.,Jang, K.,Lee, S.,Kim, J.H.,Yoon, C.S.,Kim, J.,Kim, D.H.,Ahn, H. Elsevier Sequoia 2017 JOURNAL OF ALLOYS AND COMPOUNDS Vol.694 No.-

In the present work, a unique core/shell structured TiO<SUB>2</SUB>/polyaniline (PANI) nanocomposite is successfully fabricated by chemically depositing PANI nanorods on a periodically arrayed TiO<SUB>2</SUB> inverse opal (IO) structure for energy storage applications. The morphology, composition, and electrochemical behavior of the TiO<SUB>2</SUB>/PANI core/shell structure are studied and compared with those of the PANI nanorods on stainless steel substrate. Field emission scanning electron microscopy (FE-SEM) and transmission electron spectroscopy (TEM) studies confirm the formation of a PANI nanorod shell structure on the core of the TiO<SUB>2</SUB> surface. A large specific capacity of 196.59 mA h g<SUP>-1</SUP> at a scan rate of 5 mV s<SUP>-1</SUP> is achieved for TiO<SUB>2</SUB>/PANI electrode which is comparable to that of TiO<SUB>2</SUB> (2.83 mA h g<SUP>-1</SUP>) and PANI (95.86 mA h g<SUP>-1</SUP>) electrodes. Such improvement is ascribed to PANI with a high capacity and excellent conductivity, and the TiO<SUB>2</SUB> IO structure with a large surface area and interconnected macropores, allowing efficient PANI nanorod loading, mass transport, and rapid charge transfer. A symmetric energy storage device is fabricated by assembling the two pieces of TiO<SUB>2</SUB>/PANI with a H<SUB>2</SUB>SO<SUB>4</SUB> gel electrolyte. The device shows the high energy density of 20.36 Wh kg<SUP>-1</SUP> at a power density of 500 W kg<SUP>-1</SUP> with good cycling stability (78% for 1000 cycles).

Graphene-wrapped Ag 3 PO 4 /LaCO 3 OH heterostructures for water purification under visible light

Patil, Santosh S.,Mali, Mukund G.,Roy, Animesh,Tamboli, Mohaseen S.,Deonikar, Virendrakumar G.,Patil, Deepak R.,Kulkarni, Milind V.,Al-Deyab, Salem S.,Yoon, Sam S.,Kolekar, Sanjay S.,Kale, Bharat B. Elsevier 2016 Journal of energy chemistry Vol.25 No.5

<P>We demonstrated a unique synthesis approach of graphene (GR)-wrapped Ag3PO4/LaCO3OH (APO/LCO) heterostructures by an in-situ wet chemical method. FESEM analysis reveals the formation of rhombic dodecahedrons of APO decorated with LCO and later wrapped with GR flakes. Optical studies shows two absorption edges corresponding to the band gap energies of APO (2.41 eV) and LCO (4.1 eV). Considering the absorption edge of the heterostructures in the visible region, the photocatalytic activities of photocatalysts containing different APO/LCO mass ratios were evaluated by the degradation of MB. GR-decorated composite with 20% LCO (APO/LCO20/GR) exhibited the highest photocatalytic activity for MB degradation, with a rate constant, k of 0.541 min(-1). The photocatalytic activity of APO/LCO20/GR more greatly enhanced than those of the individual constituents (APO, LCO, APO/LCO20). The enhanced photocatalytic activity of the heterostructure can be attributed to the co-catalytic effect of LCO as well as intriguing physicochemical properties of GR. To understand the enhanced photocatalytic activity of the heterostructures the photocatalytic reaction mechanism is proposed in detail. The recyclability of the APO/LCO/GR composite photocatalyst is further evaluated by reusing the catalyst in replicate photocatalytic experiments which shows consistent photocatalytic activity thereby confirms the stability and reusability of heterostructure photocatalyst. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.</P>

Role of Ceramic Coating on Electrical and Magnetic Properties of Iron Powder

N. B. Dhokey,S. Patil,S. Dhandare,V. S. Bandal 대한금속·재료학회 2014 ELECTRONIC MATERIALS LETTERS Vol.10 No.3

Soft magnetic composite is a promising second generation magnetic material. It is widely used in both DC and AC applications. In the present work, magnesium compound coated iron powder (M-SMC) was used to fabricate the toroid cores of size Ø 30 × Ø 20 × 10 mm by powder metallurgy route. All these toroid cores were cured at different temperatures ranging from 600°C to 1000°C for 30 min in argon atmosphere controlled furnace. The electrical and magnetic properties of toroid cores were analyzed by Impedance Analyzer and B-H Analyzer respectively. M-SMC core cured at 800°C showed improved electrical properties for operating frequency up to 12000 kHz whereas magnetic properties were limited to applied magnetic field of 800 A/m.

Improved Photoelectrochemical Cell Performance of Tin Oxide with Functionalized Multiwalled Carbon Nanotubes–Cadmium Selenide Sensitizer

Bhande, Sambhaji S.,Ambade, Rohan B.,Shinde, Dipak V.,Ambade, Swapnil B.,Patil, Supriya A.,Naushad, Mu.,Mane, Rajaram S.,Alothman, Z. A.,Lee, Soo-Hyoung,Han, Sung-Hwan American Chemical Society 2015 ACS APPLIED MATERIALS & INTERFACES Vol.7 No.45

<P>Here we report functionalized multiwalled carbon nanotubes (<I>f</I>-MWCNTs)–CdSe nanocrystals (NCs) as photosensitizer in photoelectrochemical cells, where <I>f</I>-MWCNTs were uniformly coated with CdSe NCs onto SnO<SUB>2</SUB> upright standing nanosheets by using a simple electrodeposition method. The resultant blended photoanodes demonstrate extraordinary electrochemical properties including higher Stern–Volmer constant, higher absorbance, and positive quenching, etc., caused by more accessibility of CdSe NCs compared with pristine SnO<SUB>2</SUB>–CdSe photoanode. Atomic and weight percent changes of carbon with <I>f</I>-MWCNTs blending concentrations were confirmed from the energy dispersive X-ray analysis. The morphology images show a uniform coverage of CdSe NCs over <I>f</I>-MWCNTs forming a core–shell type structure as a blend. Compared to pristine CdSe, photoanode with <I>f</I>-MWCNTs demonstrated a 257% increase in overall power conversion efficiency. Obtained results were corroborated by the electrochemical impedance analysis. Higher scattering, more accessibility, and hierarchical structure of SnO<SUB>2</SUB>-<I>f</I>-MWCNTs-blend–CdSe NCs photoanode is responsible for higher (a) electron mobility (6.89 × 10<SUP>–4</SUP> to 10.89 × 10<SUP>–4</SUP> cm<SUP>2</SUP> V<SUP>–1</SUP> S<SUP>1–</SUP>), (b) diffusion length (27 × 10<SUP>–6</SUP>), (c) average electron lifetime (32.2 ms), and transit time (1.15 ms).</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/aamick/2015/aamick.2015.7.issue-45/acsami.5b05385/production/images/medium/am-2015-05385e_0010.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/am5b05385'>ACS Electronic Supporting Info</A></P>

Significant enhancement of resonance magnetoelectric coupling in miniaturized lead-free NiFe₂O₄-BaTiO₃ multilayers

Patil, D.R.,Chai, Y.S.,Kim, J.H.,Nam, J.H.,Cho, J.H.,Kim, B.I.,Kim, K.H. Elsevier 2017 CURRENT APPLIED PHYSICS Vol.17 No.8

<P>With increasing demands toward device miniaturization, Pb-free magnetoelectric laminates (MELs) with a small lateral dimension of similar to 3 x 3 mm(2) have been synthesized by the tape-casting method. The MELs are composed of alternating layers of magnetostrictive NiFe2O4 and piezoelectric BaTiO3 with a uniform single layer thickness of t = 50 and 15 gm, respectively. Both laminates exhibit much larger longitudinal ME voltage coefficient alpha(E33) than the transverse ME voltage coefficient alpha(E31) at both off-resonant and resonant frequencies, which is attributed to the preferential easy-plane alignment of the magnetic moments. Furthermore, enhancement in alpha(E33) by more than 5 times has been achieved upon decreasing t from 50 to 15 mu m in both resonance and off-resonance conditions. The enhanced alpha(E33) values indicate that nearly ideal interface coupling between the ferromagnetic and piezoelectric layers is realized in the miniaturized, thinner MEL, pointing to practical application potential towards developing mass-produced, low-cost ME devices. (C) 2017 Elsevier B.V. All rights reserved.</P>

Synthesis of graphitic carbon from Pisum sativum for supercapacitor applications

Sushilkumar A. Jadhav,Pranoti H. Patil,Suchitra B. Ravan,Saurabh S. Thoravat,Tukaram D. Dongale 한국화학공학회 2023 Korean Journal of Chemical Engineering Vol.40 No.9

This work reports preparation of Pisum sativum (peas) derived graphitic carbon (PSC) and its activation with potassium hydroxide (KOH), referred to as Pisum sativum derived activated graphitic carbon (PSAC). The structure, morphology and surface area of the materials were characterized by using X-ray diffraction (XRD) analysis, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), Raman spectroscopy and Brunauer Emmet Teller (BET). The electrochemical performance of the material was investigated by using cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), cyclic stability and electrochemical impedance spectroscopy (EIS). The graphitic carbon obtained showed specific surface area of 240 m2 g−1 with pore size of 3.32nm. The electrochemical testing of activated carbon delivered specific capacitance of 517 F g−1 at 10 mV s−1 with 86% of capacitance retention after 2,000 cycles at 10 mA cm−2. It showed high specific energy of 35 Wh kg−1 at specific power 645 W kg−1.

Towards high performance unique microstructures of Co₉S₈//CoFe₂O₄ for asymmetric supercapacitor

Patil, S.J.,Lokhande, A.C.,Park, J.S.,Kim, J.H.,Kim, Y.B.,Choi, B.C.,Park, S.H.,Jung, S.H.,Lee, D.W. Elsevier 2018 Journal of industrial and engineering chemistry Vol.61 No.-

<P><B>Abstract</B></P> <P>Herein, we have proposed asymmetric supercapacitor device to achieve empirical electrochemical performance based on binder-free Co<SUB>9</SUB>S<SUB>8</SUB> and CoFe<SUB>2</SUB>O<SUB>4</SUB> electrodes. The unique architecture and porous surface of the prepared electrodes were analyzed using electron microscopy and Brunauer–Emmett–Teller technique. Electrochemical properties of Co<SUB>9</SUB>S<SUB>8</SUB> and CoFe<SUB>2</SUB>O<SUB>4</SUB> electrode were employed in a three-electrode cell-configuration that exhibits a capacitance of 817 and 1203Fg<SUP>−1</SUP>, respectively. Co<SUB>9</SUB>S<SUB>8</SUB>//CoFe<SUB>2</SUB>O<SUB>4</SUB> asymmetric supercapacitor reveals a high capacitance of 79.11Fg<SUP>−1</SUP> with 28.88Whkg<SUP>−1</SUP> energy density and superior cyclic stability over 2500 cycles (∼87%). These results suggest that prepared electrodes have a great potential for practical applications.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Unique-microstructures of C<SUB>o9</SUB>S<SUB>8</SUB> and CoFe<SUB>2</SUB>O<SUB>4</SUB> electrodes were prepared. </LI> <LI> C<SUB>o9</SUB>S<SUB>8</SUB>//CoFe<SUB>2</SUB>O<SUB>4</SUB> supercapacitor exhibits an energy density of 28.88Whkg<SUP>−1</SUP>. </LI> <LI> The assembled Co<SUB>9</SUB>S<SUB>8</SUB>//CoFe<SUB>2</SUB>O<SUB>4</SUB> supercapacitor delivers a superior rate capability. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>The Ragone plot shows the electrochemical performance of the Co<SUB>9</SUB>S<SUB>8</SUB>//CoFe<SUB>2</SUB>O<SUB>4</SUB> asymmetric supercapacitor device, and inset shows the BET surface area plot.</P> <P>[DISPLAY OMISSION]</P>