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).

Triton-X mediated interconnected nanowalls network of cadmium sulfide thin films via chemical bath deposition and their photoelectrochemical performance

Vanalakar, S.A.,Mali, S.S.,Jo, E.A.,Kim, J.Y.,Kim, J.H.,Patil, P.S. Elsevier 2014 SOLID STATE SCIENCES Vol.36 No.-

Thin films of cadmium sulfide (CdS) have been wet chemically deposited onto fluorine-doped tin oxide (FTO) coated conducting glass substrates by using non-ionic surfactant; Triton-X 100. An aqueous solution contains cadmium sulphate as a cadmium and thiourea as sulphur precursor. Ammonia used as a complexing agent. The results of measurements of the x-ray diffraction, Raman spectroscopy, optical spectroscopy, energy dispersive spectroscopy, scanning electron microscopy, Brunauer Emmett Teller (BET) surface areas and atomic force microscopy were used for the characterization of the films. These results revealed that the films are polycrystalline, consisting of CdS cubic phase. The films show a direct band gap with energy 2.39 eV. The films show interconnected nanowalls like morphology with well-defined surface area. Finally, the photoelectrochemical (PEC) performance of Triton-X mediated CdS thin film samples were studied. The sample shows photoelectrochemical (PEC) performance with maximum short circuit current density (J<SUB>sc</SUB>) 1.71 mA/cm<SUP>2</SUP> for larger area (1 cm<SUP>2</SUP>) solar cells.

3D yolk-shell NiGa2S4 microspheres confined with nanosheets for high performance supercapacitors

Liu, S.,Kim, K.,Yun, J.,Kundu, A.,Sankar, K. V.,Patil, U.,Ray, C.,ChanJun, S. Royal Society of Chemistry 2017 Journal of Materials Chemistry A Vol.5 No.13

<P>Recent advances in the development of two-dimensional transition-metal chalcogenides (2D TMCs) have opened up new avenues for supercapacitor applications. However, they still suffer from limited specific capacitance and poor rate capability due to their poor interfacial properties and simple geometry. Here, we propose a facile strategy for the synthesis of yolk-shell NiGa2S4 microspheres comprising crumpled nanosheets supported on nickel foam. The robust structure not only highly facilitates the electron and charge transportation but also efficiently alleviates the volume expansion during redox reactions, contributing to excellent electrochemical behaviors in terms of specific capacitance and rate capability. Significantly, an asymmetric supercapacitor based on the prepared NiGa2S4 as the positive electrode and N, S-codoped graphene/Fe2O3 (N, S-G/Fe2O3) as the negative electrode delivers a high energy density of 43.6 W h kg(-1) at a power density of 961 W kg(-1) and retains an energy density of 22.2 W h kg(-1) even at 15 974 W kg(-1). These impressive results may provide a new perspective to develop high energy and power density storage systems for practical applications.</P>

A chemical approach for synthesis of photoelectrochemically active Cu₂ZnSnS₄ (CZTS) thin films

Suryawanshi, M.P.,Shin, S.W.,Ghorpade, U.V.,Gurav, K.V.,Agawane, G.L.,Hong, C.W.,Yun, J.H.,Patil, P.S.,Kim, J.H.,Moholkar, A.V. Association for Applied Solar Energy ; Elsevier Sc 2014 SOLAR ENERGY -PHOENIX ARIZONA THEN NEW YORK- Vol.110 No.-

A cost-effective chemical approach is developed for the synthesis of photoelectrochemically active Cu<SUB>2</SUB>ZnSnS<SUB>4</SUB> (CZTS) thin films. More specifically, CZTS precursor thin films are prepared by the sequential deposition of Cu<SUB>2</SUB>SnS<SUB>3</SUB> and ZnS layers using a successive ionic adsorption and reaction (SILAR) technique. The CZTS precursor thin films are sulfurized at different temperatures ranging from 500 to 575<SUP>o</SUP>C at intervals of 25<SUP>o</SUP>C. The influence of different sulfurization temperatures on the structural, compositional, morphological, and optical properties, as well as on the photoelectrochemical performance is studied. The films sulfurized at 575<SUP>o</SUP>C showed a prominent kesterite phase with a nearly stoichiometric composition, dense microstructure with the desired thickness, and an optical band gap energy of 1.47eV. The photoelectrochemical (PEC) cell fabricated using CZTS thin film sulfurized at 575<SUP>o</SUP>C showed the highest short circuit current density (J<SUB>sc</SUB>) of 8.27mA/cm<SUP>2</SUP> with a power conversion efficiency (η) of 1.06%.

Electrochemical Detection of Hydroxychloroquine Sulphate Drug using CuO/GO Nanocomposite Modified Carbon Paste Electrode and its Photocatalytic Degradation

G. S. Shaila,Dinesh Patil,Naeemakhtar Momin,J. Manjanna 한국전기화학회 2024 한국전기화학회지 Vol.27 No.1

The antimalarial drug hydroxychloroquine sulphate (HCQ) has taken much attention during the first COVID-19 pandemic phase for the treatment of severe acute respiratory infection (SARI) patients. Hence it is interest to study the electrochemical properties and photocatalytic degradation of the HCQ drug. Copper oxide (CuO) nanoparticles, graphene oxide (GO) and CuO/ GO NC (nanocomposite) modified carbon paste electrodes (MCPE) are used for the detection of HCQ in an aqueous medium. Electrochemical behaviour of HCQ (20 μM) was observed using CuO/MCPE, GO/MCPE and CuO/GO NC/MCPE in 0.1 M phosphate buffer at pH 7 with a scan rate of 20 to 120 mV s−1 by cyclic voltammetry (CV). Differential pulse voltammetry (DPV) of HCQ was performed for 0.6 to 16 μM HCQ. The CuO/GO NC/MCPE showed a reasonably good sensitivity of 0.33 to 0.44 μA μM cm–2 with LOD of 69 to 92 nM for HCQ. Furthermore, the CuO/GO NC was used as a catalyst for the photodegradation of HCQ by monitoring its UV-Vis absorption spectra. About 98% was degraded in about 34 min under visible light and after 4 cycles it was 87%. The improved photocatalytic activity may be attributed to decrease in bandgap energy and enhanced ability for the electrons to migrate. Thus, CuO/GO NC showed good results for both sensing and degradation applications as well as reproducibility.

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>

Graphene-nanosheet wrapped cobalt sulphide as a binder free hybrid electrode for asymmetric solid-state supercapacitor

Patil, S.J.,Kim, J.H.,Lee, D.W. Elsevier 2017 Journal of Power Sources Vol.342 No.-

<P><B>Abstract</B></P> <P>A binder-free graphene-nanosheets wrapped Co<SUB>3</SUB>S<SUB>4</SUB> hybrid electrode is prepared on conductive Ni-foam via a simple two-step hydrothermal process. The physicochemical characterization such as X-ray diffraction, Raman spectroscopy, and electron microscopy revealed the formation of a Co<SUB>3</SUB>S<SUB>4</SUB>-rGO hybrid electrode with a large specific surface area (30 m<SUP>2</SUP> g<SUP>−1</SUP>). The integrated structure of the Co<SUB>3</SUB>S<SUB>4</SUB>-rGO hybrid electrode exhibits an areal and specific capacitance of 8.33 F cm<SUP>−2</SUP> and 2314 F g<SUP>−1</SUP>, respectively. The Co<SUB>3</SUB>S<SUB>4</SUB>-rGO hybrid electrode charges within 30 s, while the energy density remains high as 54.32 Wh kg<SUP>−1</SUP> at an outstanding power density of 6.25 kW kg<SUP>−1</SUP> with 92.6% excellent electrochemical cyclic stability over 1000 cycles. The asymmetric supercapacitor device is fabricated using Co<SUB>3</SUB>S<SUB>4</SUB> and Co<SUB>3</SUB>S<SUB>4</SUB>-rGO as positive and negative electrodes, respectively, which exhibit an areal capacitance of ∼164 mF cm<SUP>−2</SUP> with reasonable cyclic stability (89.56% over 5000 cycles). The Co<SUB>3</SUB>S<SUB>4</SUB>/Co<SUB>3</SUB>S<SUB>4</SUB>-rGO supercapacitor reveals a high energy density of 1.09 Wh kg<SUP>−1</SUP> at a power density of 398 W kg<SUP>−1</SUP>, and 0.31 Wh kg<SUP>−1</SUP> energy density can be retained even at a power density of 750 W kg<SUP>−1</SUP>. The superior electrochemical activities of the Co<SUB>3</SUB>S<SUB>4</SUB> based electrode suggest considerable promise for high-performance energy storage applications.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Co<SUB>3</SUB>S<SUB>4</SUB>-rGO was synthesized by binder-free simple two-step hydrothermal process. </LI> <LI> Co<SUB>3</SUB>S<SUB>4</SUB>-rGO electrode exhibits a high areal capacitance with ultra-high energy density. </LI> <LI> Co<SUB>3</SUB>S<SUB>4</SUB>/Co<SUB>3</SUB>S<SUB>4</SUB>-rGO asymmetric supercapacitor device shows a superior cyclic stability. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>The schematic of charge/discharge mechanism occurred at the interface of active electrode/electrolyte.</P> <P>[DISPLAY OMISSION]</P>

Self-assembled Ni₃S₂//CoNi₂S₄ nanoarrays for ultra high-performance supercapacitor

Patil, S.J.,Kim, J.H.,Lee, D.W. Elsevier 2017 Chemical Engineering Journal Vol. No.

<P><B>Abstract</B></P> <P>In this study, Ni<SUB>3</SUB>S<SUB>2</SUB>-nanorod and CoNi<SUB>2</SUB>S<SUB>4</SUB>-microflower structures have been prepared using a simple one-step hydrothermal method. The complete absence of an additive polymeric binder enabled the electrode to obtain structural purity and excellent electrochemical activity. The formation of the nanorod and micro flowers (µflowers) was clearly visualized by the surface microstructural study. Ni<SUB>3</SUB>S<SUB>2</SUB>-nanorod and CoNi<SUB>2</SUB>S<SUB>4</SUB>-µflower electrodes show a significantly higher specific capacitance of 982.9Fg<SUP>−1</SUP> and 2098.95Fg<SUP>−1</SUP>, respectively, with outstanding electrochemical cyclic stability performance. The CoNi<SUB>2</SUB>S<SUB>4</SUB>-µflower electrode can achieve an energy density of 82.98Whkg<SUP>−1</SUP> with a power density of 9.63kWkg<SUP>−1</SUP>. In addition, a 91% capacitive retention remains after 2000 cycles at a scan rate of 100mVs<SUP>−1</SUP>. The designed hybrid asymmetric supercapacitor, based on Ni<SUB>3</SUB>S<SUB>2</SUB>-nanorod//CoNi<SUB>2</SUB>S<SUB>4</SUB>-µflower electrodes, exhibits a specific capacitance of 54.92Fg<SUP>−1</SUP> at a scan rate of 5mVs<SUP>−1</SUP>. The assembled asymmetric supercapacitor has an energy density of 6.6Whkg<SUP>−1</SUP> while delivering a power density of 820Wkg<SUP>−1</SUP>. The capacitive retention of the initial capacitance remains desirable at 89.13% after 5000 CV cycles at a scan rate of 100mVs<SUP>−1</SUP>. The present work manifests a vision for the fabrication of self-assembled, binder-free electrodes for high-performance hybrid supercapacitor application.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The self-assembled unique microstructures were obtained by a hydrothermal method. </LI> <LI> CoNi<SUB>2</SUB>S<SUB>4</SUB>-µflower arrays showed a high specific capacitance of 2098.95Fg<SUP>−1</SUP>. </LI> <LI> Asymmetric supercapacitor designed with Ni<SUB>3</SUB>S<SUB>2</SUB>-nanorod and CoNi<SUB>2</SUB>S<SUB>4</SUB>-µflower arrays. </LI> <LI> Ni<SUB>3</SUB>S<SUB>2</SUB>//CoNi<SUB>2</SUB>S<SUB>4</SUB> delivers energy density of 6.6Whkg<SUP>−1</SUP> at a power of 820Wkg<SUP>−1</SUP>. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

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>

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

S.J. Patil,A.C. Lokhande,J.S. Park,J.H. Kim,Y.B. Kim,B.C. Choi,S.H. Park,S.H. Jung,이동원 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.61 No.-

Herein, we have proposed asymmetric supercapacitor device to achieve empirical electrochemical performance based on binder-free Co9S8 and CoFe2O4 electrodes. The unique architecture and porous surface of the prepared electrodes were analyzed using electron microscopy and Brunauer–Emmett–Teller technique. Electrochemical properties of Co9S8 and CoFe2O4 electrode were employed in a three-electrode cell-configuration that exhibits a capacitance of 817 and 1203 F g−1, respectively. Co9S8//CoFe2O4 asymmetric supercapacitor reveals a high capacitance of 79.11 F g−1 with 28.88 Wh kg−1 energy density and superior cyclic stability over 2500 cycles (∼87%). These results suggest that prepared electrodes have a great potential for practical applications.