Chemical synthesis of ZnO nanorods: Investigations of electrochemical performance and photo-electrochemical water splitting applications

Deshmukh, P.R.,Sohn, Youngku,Shin, Weon Gyu Elsevier 2017 JOURNAL OF ALLOYS AND COMPOUNDS Vol.711 No.-

<P><B>Abstract</B></P> <P>Zinc Oxide (ZnO) nanorods were prepared by facile and inexpensive chemical route at low temperature. X-ray diffraction study confirms the formation of hexagonal wurtzite crystal structure with high orientation along the c-axis. FE-SEM images show a vertical alignment of ZnO nanorods to the substrate surface, whose average diameter and length is 1.33 and 15 μm, respectively. Electrochemical performance and photo-electrochemical water splitting of ZnO nanorods are investigated in 1 M Na<SUB>2</SUB>SO<SUB>4</SUB> electrolyte using the different electrochemical techniques. Electrochemical study of ZnO nanorods exhibits the maximum areal capacitance of 29.36 mFcm<SUP>−2</SUP> in the negative potential window, which is higher than the areal capacitance of 10.84 mFcm<SUP>−2</SUP> in the positive potential window at the scan rate of 5 mVs<SUP>−1</SUP>. ZnO nanorods show the excellent stability of 97% over the 3000 cycles in both potential windows. Photo-electrochemical water splitting demonstrates the fast photo-response with 0.098% photo-conversion efficiency.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Low temperature chemical synthesis of ZnO nanorods. </LI> <LI> Study of ZnO nanorods in electrochemical and PEC water splitting applications. </LI> <LI> ZnO nanorods exhibits the maximum areal capacitance of 29.36 mFcm<SUP>−2</SUP>. </LI> <LI> ZnO nanorods demonstrated the superb 97% stability over 3000 cycles. </LI> <LI> PEC water splitting showed the fast photoresponse and photo conversion efficiency. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Electrochemical performance of facile developed aqueous asymmetric (Fe,Cr)₂O₃//MnO₂ supercapacitor

Deshmukh, P.R.,Sohn, Youngku,Shin, Weon Gyu Elsevier 2018 ELECTROCHIMICA ACTA Vol.285 No.-

<P><B>Abstract</B></P> <P>The present study demonstrate the development of novel aqueous asymmetric supercapacitor based on polygonal integrated oxide layer ((Fe,Cr)<SUB>2</SUB>O<SUB>3</SUB>) as the anode and spherical MnO<SUB>2</SUB> nanoparticles as the cathode. The polygonal (Fe,Cr)<SUB>2</SUB>O<SUB>3</SUB> integrated oxide layer was obtained by the simple thermal oxidation method and low-cost, scalable chemical route was employed for the synthesis of spherical MnO<SUB>2</SUB> nanoparticles. Furthermore, electrochemical investigations of asymmetric supercapacitor (ASC) studied in aqueous electrolytes show an extended operating voltage of 1.6 and 2.0 V with the maximum specific capacitance of 34 and 37 Fg<SUP>-1</SUP> in KOH and Na<SUB>2</SUB>SO<SUB>4</SUB>, respectively. The observed energy density and power density of ASC in Na<SUB>2</SUB>SO<SUB>4</SUB> (or KOH) electrolyte is 20.89 (or 12.36) Whkg<SUP>−1</SUP> and 2173.913 (or 1739) Wkg<SUP>−1</SUP>, respectively. ASC shows the better capacitance retention over the 5000 cycles in both the electrolytes. Therefore, present study open-up new construction of inexpensive petty (Fe,Cr)<SUB>2</SUB>O<SUB>3</SUB> anode material for the development of high energy density ASCs.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Preparation of (Fe,Cr)<SUB>2</SUB>O<SUB>3</SUB> oxide layer and MnO<SUB>2</SUB> nanoparticles as a binder free electrode materials. </LI> <LI> (Fe,Cr)<SUB>2</SUB>O<SUB>3</SUB> and MnO<SUB>2</SUB> shows the specific capacitance of 372 and 174 Fg<SUP>-1</SUP> in Na<SUB>2</SUB>SO<SUB>4</SUB> electrolyte. </LI> <LI> Development of aqueous asymmetric supercapacitor made from (Fe,Cr)<SUB>2</SUB>O<SUB>3</SUB> and MnO<SUB>2</SUB>. </LI> <LI> Asymmetric supercapacitor shows the high specific capacitance of 37 Fg<SUP>-1</SUP> in Na<SUB>2</SUB>SO<SUB>4</SUB> electrolyte. </LI> <LI> Asymmetric supercapacitor shows the high-energy density of 20.89 Whkg<SUP>−1</SUP> in Na<SUB>2</SUB>SO<SUB>4</SUB> electrolyte. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Ultrasound Assisted Green Synthesis of Silver and Iron Oxide Nanoparticles Using Fenugreek Seed Extract and Their Enhanced Antibacterial and Antioxidant Activities

Deshmukh, Aarti R.,Gupta, Arvind,Kim, Beom Soo Hindawi 2019 BioMed research international Vol.2019 No.-

<P>This study reports a facile and ecofriendly approach for the ultrasound assisted synthesis of silver and iron oxide nanoparticles and their enhanced antibacterial and antioxidant activities. The fenugreek seed extract was used as reducing, capping, and stabilizing agent in the synthesis of nanoparticles. The transmission electron microscopy results showed that nanoparticles synthesized by ultrasonication have a smaller size (~20 nm) as compared to the nanoparticles fabricated by magnetic stirring (~40 nm). The color change of the solution from milky white to brown suggested the formation of silver nanoparticles which was confirmed by the presence of an absorbance peak at 396 nm. The results of powder X-ray diffraction and energy dispersive X-ray spectroscopy confirmed the crystallinity and elements present in nanoparticles synthesized using fenugreek seed extract. Fourier transform infrared analysis showed that the fenugreek seed phytochemicals were coated on the nanoparticle surface. Thermal gravimetric analysis showed the thermal degradation and stability of nanoparticles. Magnetization study of iron oxide nanoparticles confirmed the superparamagnetic nature. The silver nanoparticles showed antibacterial activities against both gram-negative (<I>Escherichia coli</I>) and gram-positive (<I>Staphylococcus aureus</I>) bacteria, while no antibacterial activities were observed for iron oxide nanoparticles. The ultrasound assisted nanoparticles showed higher stability and antibacterial and antioxidant activity compared with the nanoparticles fabricated by magnetic stirring.</P>

Integrated control scheme for dynamic power management with improved voltage regulation in DC microgrid

Deshmukh, Rohit R.,Ballal, Makarand S. The Korean Institute of Power Electronics 2020 JOURNAL OF POWER ELECTRONICS Vol.20 No.6

This article presents an integrated control scheme to improve power sharing for power management and voltage regulation in DC microgrids. The proposed scheme considers the available power and the stochastic nature of sources to achieve adequate power sharing among them. Therefore, it achieves effective utilization of each source. In addition, the effective use of energy storage systems (ESSs) is also achieved by reducing their charging/discharging cycles. The proposed control scheme improves voltage regulation under various operating conditions. It enhances the stability of microgrids and improves their dynamic response. The proposed control scheme is adaptive to changes in the source or load. It operates without historical/previous data, which reduces the computational burden. The proposed control scheme is experimentally validated under diverse operating conditions.

Room temperature electroless Ni-coating on boron particles: Physicochemical and oxidation-resistance properties

P.R. Deshmukh,Youngku Sohn,Weon Gyu Shin 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.91 No.-

Ni nanoparticles were coated on irregularly shaped micron sized boron particles by facile electroless Nidepositionmethod. Four kinds of Ni-coated boron particles were prepared using four different simplepaths during the electroless deposition process: no rinsing and no drying (Path A), only drying (Path B),both rinsing and drying (Path C), and only rinsing (Path D). Surface morphology confirmed the Ninanoparticlescoating on the surface of boron particles. The size of the Ni nanoparticles varied between 10and 120 nm with respect to the chosen paths used for preparation. The Ni nanoparticle's size was alsostudied using TEM and found to be consistent with the surface morphology results. XRD measurement ofthe Ni-coated boron particles showed the formation of crystalline Ni nanoparticles. EDAX and XPS resultsshowed the presence of the primary B and Ni elements in the obtained samples. Thermogravimetricanalysis conducted in air atmosphere found the boron particles had enhanced oxidation resistance afterthe coating of Ni nanoparticles. The Ni-coated boron particles showed a shift in exothermic peak to alower temperature and higher heat evolution than the pure boron, recommending the use of Ni-coatedboron particles in solid fuel in missile/rocket engines, and high temperature applications.

A Facile Synthesis of 1,3,4,6-Tetrahydro-1,6-benzodiazocine-2,5-diones

S.R.Bhusare,D.V.Jarikote,R.R.Deshmukh,W.N.Jadhav,R.P.Pawar,Y.B.Vibhute 대한화학회 2003 Bulletin of the Korean Chemical Society Vol.24 No.9

Growth of Polyaniline Nanofibers for Supercapacitor Applications Using Successive Ionic Layer Adsorption and Reaction (SILAR) Method

P. R. Deshmukh,S. N. Pusawale,N. M. Shinde,C.D. Lokhande 한국물리학회 2014 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.65 No.1

We report the synthesis of polyaniline nanofibers using the successive ionic layer adsorptionand reaction (SILAR) method. The structural study shows the amorphous nature of polyaniline. The formation of polyaniline nanofibers has been revealed by scanning electron microscopy (SEM)whereas the confirmation of polyaniline material is obtained from Fourier transform infrared (FT-IR)spectroscopy. A plausible explanation illustrating the growth mechanism is presented. A maximumspecific capacitance of 1078 F.g−1 at a scan rate of 5 mV.s−1 is obtained. The charge-dischargebehavior shows a maximum specific power of 1.2 kW.kg−1 and specific energy of 64 Wh.kg−1. The ease of the synthesis and the interesting electrochemical properties indicate that polyanilinenanofibers are promising materials for supercapacitor applications.

A Facile Synthesis of 1,3,4,6-Tetrahydro-1,6-benzodiazocine-2,5-diones

Bhusare, S. R.,Jarikote, D. V.,Deshmukh, R. R.,Jadhav, W. N.,Pawar, R. P.,Vibhute, Y. B. Korean Chemical Society 2003 Bulletin of the Korean Chemical Society Vol.24 No.9

Facile preparation of superhydrophilic and underwater superoleophobic stainless steel mesh for oil–water separation

명재원,Prashant.R. Deshmukh,신원규 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.120 No.-

Effective oil–water separation is necessary to cope with frequent oil spill accidents, which pose huge risksto the marine ecosystem. Among existing oil–water separation methods, gravitational filtration is themost efficient. When super-wetting materials are used for gravitational filtration, they have the meritof high efficiency but they still have the disadvantages of high price, low eco-friendliness, and complexprocedures. To overcome those problems, we fabricated a stainless steel mesh by a one-step methodvia an annealing process. The annealed mesh achieved both superhydrophilicity and superoleophilicity. For oil–water separation, the annealed mesh, which was pre-wetted by water, demonstrated underwatersuperoleophobicity. Thus, this study confirmed that the proposed system can separate various oily mixtureswith high efficiency (>99 %) and it exhibits underwater anti-oil-fouling.

Spray drying formation of metal oxide (TiO₂ or SnO₂) nanoparticle coated boron particles in the form of microspheres and their physicochemical properties

Lee, Haneol,Deshmukh, P.R.,Kim, Jong Hun,Hyun, Hyung Soo,Sohn, Youngku,Shin, Weon Gyu Elsevier 2019 JOURNAL OF ALLOYS AND COMPOUNDS Vol.810 No.-

<P><B>Abstract</B></P> <P>In the present study, metal oxide (TiO<SUB>2</SUB> or SnO<SUB>2</SUB>) nanoparticles were coated on boron particles using a facile spray drying technique. The coating of metal oxide nanoparticles on the boron surface was varied by changing the weight ratio of metal oxide nanoparticles to boron particles. The crystalline structure of the metal oxide nanoparticles was mainly retained without any additional phase formation on the metal oxide coated boron particles, as identified by XRD. FIB-SEM images showed that the TiO<SUB>2</SUB> or SnO<SUB>2</SUB> coated boron particles formed microspheres with diameters between 5 and 10 μm. FIB-cross sectional images indicated the microspheres had a porous structure, and every individual boron particle was coated by metal oxide nanoparticles. The line scanning profile, elemental mapping and corresponding EDAX spectra results indicated the boron particles were well coated with metal oxide nanoparticles, and confirmed the presence of respective elements in the samples, respectively. TEM study showed the fine coating of metal oxide nanoparticles on the surface of the boron particles. The surface elemental composition was identified with XPS, and revealed the strong interaction between the metal oxide and boron particles. The thermal behavior of the boron, metal oxide and metal oxide nanoparticle coated boron particles was studied in the presence of nitrogen and air atmosphere using thermogravimetric analysis. The TGA of the metal oxide nanoparticle coated boron particles showed enhanced oxidation-resistance performance in the presence of air atmosphere.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Metal oxide nanoparticle coating on boron particles using spray-drying technique. </LI> <LI> Porous microspheres of metal oxide nanoparticle coated boron particles. </LI> <LI> Well distribution and coating of metal oxide nanoparticles on the boron particles. </LI> <LI> Enhanced oxidation-resistance performance of metal oxide coated boron particles. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>