02927nas a2200325 4500008004100000245010200041210006900143260000800212490000600220520185800226653003302084653001302117653001202130653003002142653002002172653002502192653001802217653001402235653001002249653002102259653001602280653002002296653002002316653003902336100002302375700002902398700003002427700001802457856012602475 2017 eng d00aCopper Cobalt Sulfide Nanosheets Realizing a Promising Electrocatalytic Oxygen Evolution Reaction0 aCopper Cobalt Sulfide Nanosheets Realizing a Promising Electroca cSEP0 v73 a

Nanostructured CuCo2S4, a mixed metal thiospinel, is found to be a benchmark electrocatalyst for oxygen evolution reaction (OER) in this study with a low overpotential, a low Tafel slope, a high durability, and a high turnover frequency (TOF) at lower mass loadings. Nanosheets of CuCo2S4 are realized from a hydrothermal synthesis method in which the average thickness of the sheets is found to be in the range of 815 nm. Aggregated nanosheets form a highly open hierarchical structure. When used as an electrocatalyst, CuCo2S4 nanosheets offer an overpotential value of 310 mV at a 10 mA cm(2) current density, which remains consistent for 10000 measured cycles in a 1 M KOH electrolyte. A chronoamperometric study reveals constant oxygen evolution for 12 h at a 10 mV s(-1) scan rate without any degradation of the activity. Furthermore, the calculated mass activity of the CuCo2S4 electrocatalyst is found to be 14.29 A/g and to afford a TOF value of 0.1431 s(-1) at 310 mV at a mass loading of 0.7 mg cm(-2). For comparison, nanostructures of Co3S4 and Cu0.5Co2.5S4 have been synthesized using a similar method followed for CuCo2S4. When compared to the OER activities among these three thiospinels and standard IrO2, CuCo2S4 nanosheets offered the highest OER activities at the same mass loading (0.7 mg/cm(-2)). Extensive X-ray photoelectron spectroscopy and electron paramagnetic resonance analyses for a mechanistic study reveal that introduction of Cu into the Co3S4 lattice enhances the oxygen evolution and kinetics by offering Cu2+ sites for utilitarian adsorption of OH, O, and OOH reactive species and also by offering a highly active high-spin state of octahedral Co3+ for OER catalysis.

10aBifunctional Electrocatalyst10aCatalyst10aCuco2s410aEfficient Electrocatalyst10aelectrocatalyst10aElectronic-structure10aNanoparticles10aNanosheet10aoxide10aoxygen evolution10aperformance10aRecent Progress10aWater oxidation10aWater Splitting Hydrogen Evolution1 aChauhan, Meenakshi1 aReddy, Kasala, Prabhakar1 aGopinath, Chinnakonda, S.1 aDeka, Sasanka uhttps://library.ncl.res.in/content/copper-cobalt-sulfide-nanosheets-realizing-promising-electrocatalytic-oxygen-evolution02139nas a2200289 4500008004100000022001400041245016200055210006900217260000800286300001600294490000600310520116500316653001401481653003001495653001301525653001001538653002101548653001001569653003001579653001601609653001601625653000901641100002001650700002401670700002401694856013101718 2017 eng d a2040-336400aNiZn double hydroxide nanosheet-anchored nitrogen-doped graphene enriched with the gamma-NiOOH phase as an activity modulated water oxidation electrocatalyst0 aNiZn double hydroxide nanosheetanchored nitrogendoped graphene e cSEP a12590-126000 v93 a

Herein, we report a facile solvothermal process to synthesize an active electrocatalyst for the oxygen evolution reaction (OER) in an alkaline medium by anchoring nanosheets of a NiZn double hydroxide over nitrogen doped reduced graphene oxide after enriching the system with the γ-NiOOH phase. This catalyst possesses a thin, porous and open layered structure, which makes the system more efficient and accessible for a better electrochemical water oxidation reaction. Moreover, we experimentally demonstrated that incorporation of Zn via a single-step solvothermal method provides an easy approach to obtain plenty of exposed γ-NiOOH phases to make the system more viable for OER with a small overpotential of 290 mV at 10 mA cm−2 and a Tafel slope of 44 mV per decade. In addition to this, the oxophilic nature of Zn in the (Zn)Ni-LDH/N-rGO catalyst helps to improve the long-term stability of the whole system. The obtained results open up possibilities for the design of future robust OER electrocatalysts by the use of very cheap and abundant materials like Ni and Zn in place of expensive Ir and Ru in the present commercial electrocatalysts.

10acatalysis10aEfficient Electrocatalyst10akinetics10aMetal10aNickel-Hydroxide10aoxide10aOxygen Evolution Reaction10aperformance10aXPS Spectra10azinc1 aNadeema, Ayasha1 aDhavale, Vishal, M.1 aKurungot, Sreekumar uhttps://library.ncl.res.in/content/nizn-double-hydroxide-nanosheet-anchored-nitrogen-doped-graphene-enriched-gamma-niooh-phase01634nas a2200229 4500008004100000022001400041245007600055210006900131260000800200300001200208490000700220520091200227653001201139653002401151653002101175653001001196653001901206100002301225700002601248700002201274856010801296 2021 eng d a1949-307X00aMagnetic and magnetoelastic properties of Ni-substituted cobalt ferrite0 aMagnetic and magnetoelastic properties of Nisubstituted cobalt f cJAN a25042050 v123 aIn this letter, magnetic and magnetostriction studies were performed on spinel ferrite Co1-xNixFe2O4 (CNF series) with 0.0 < x < 0.5. All the samples were synthesized by the conventional ceramic method and confirmed to be forming pure spinel phase. The unit cell parameter showed gradual decrease with increasing Ni content. A linear decrease in saturation magnetization (M-s) and coercivity (H-c) was observed with increasing Ni substitution, which could be attributed to reduced magneto-crystalline anisotropy. The room temperature magnetostriction studies revealed a slow decrease in maximum magnetostriction, and interestingly, for 20% reduction of cobalt concentration, i.e., for x = 0.2, a magnetostrictive strain of -164 ppm and substantially high stress sensitivity of -56 x 10(-6) A(-1) m were observed, making Co0.8Ni0.2Fe2O4 suitable for application as a magnetostrictive stress-sensing material.10aFerrite10aMagnetism in solids10aMagnetostriction10aoxide10astress sensing1 aBhame, Shekhar, D.1 aShirolkar, Mandar, M.1 aJoy, Pattayil, A. uhttps://library.ncl.res.in/content/magnetic-and-magnetoelastic-properties-ni-substituted-cobalt-ferrite02252nas a2200265 4500008004100000022001400041245009400055210006900149260000800218300001500226490000600241520142600247653001401673653001901687653002101706653001101727653000901738653001001747653001101757100002301768700002801791700002201819700002601841856011901867 2022 eng d a2365-654900aCatalytic activity of CuFe2O4 spinel oxide for liquid-phase oxidation of cinnamyl alcohol0 aCatalytic activity of CuFe2O4 spinel oxide for liquidphase oxida cFEB ae2021044410 v73 a

CuFe2O4 spinel oxide catalyst was synthesized by sol-gel and co-precipitation methods for liquid phase oxidation of Cinnamyl alcohol (CnOH) to Cinnamaldehydes (CnHO) using tert-Butyl hydroperoxide (TBHP) as oxidising agent. Spinel oxide catalyst was characterized by different techniques such as X-ray diffraction (XRD), N-2 adsorption-desorption, BET surface area, and X-ray photoelectron spectroscopy (XPS) to understand the structural, physical properties and oxidation state of the catalyst. The result shows that catalyst prepared by sol-gel method was found higher surface area and smaller crystalline size than co-precipitation method. XPS data confirm the formation of Cu2+ in the spinel which helps to improve the catalytic activity of oxidation. This reaction follows radical mechanism, and exhibited 76.7 % of CnOH conversion and 68.4 % of CnHO, and 24.8 % benzaldehyde (benzald) selectivity using TBHP at 60 degrees C. Kinetic data reveal that 41.2 kJ/mol of activation energy for the reaction. The higher activity of spinel oxide catalyst could be due synergetic effect of spinel (88 %) and oxides (12 %) formed in the catalyst, which helps to provide the oxygen during reaction. The contribution of Cu2+ is higher in sol-gel than co-precipitation, which may provide the better reactivity of catalyst. This work helps to select the effective and cost-effective catalyst for the oxidation of CnOH.

10aCatalysts10aCinnamaldehyde10aCinnamyl Alcohol10aCupper10airon10aoxide10aspinel1 aDange, Rutvija, M.1 aNiphadkar, Prashant, S.1 aBokade, Vijay, V.1 aNandanwar, Sachin, U. uhttps://library.ncl.res.in/content/catalytic-activity-cufe2o4-spinel-oxide-liquid-phase-oxidation-cinnamyl-alcohol02016nas a2200241 4500008004100000022001400041245007600055210006900131260000800200300001100208490000700219520127000226653001201496653001901508653002101527653001001548653001901558100001901577700002201596700002601618700002201644856010801666 2022 eng d a0019-452200aMagnetostriction studies on transition metal substituted cobalt ferrite0 aMagnetostriction studies on transition metal substituted cobalt  cAUG a1005990 v993 a

Structural, magnetic and microstructural properties of transition metal (TM) substituted cobalt ferrite Co0.9TM0.1Fe2O4 (where TM = Ti, Cr, Mn, Ni and Cu and Zn) were investigated. The present study shows marked dependence of the magnetostriction on the concentration of the substituted transition metal ions for Cobalt in CoFe2O4. The magnetic characteristics of the prepared compositions such as coercivity, anisotropy constant and saturation magnetization changed significantly on transition metal substitution. The present study shows the way to tune the anisotropy of cobalt ferrite by effective substitution of other transition metal ions for Co which subsequently affects the stress sensing performance by changing the slope of the magnetostriction curve. Apart from the magnetic properties the microstructure can also be effectively modified by substitution of other transition metal ions. Only 10% substitution of cobalt showed drastic influence on magnetostriction and slope of magnetostriction curve. The composition with 10% nickel Co0.9Ni0.1Fe2O4 exhibited maximum slope for the magnetostriction curve of -53.7 ppm/Oe, along with reasonably high magnitude of strain of 186 ppm making it a suitable for exploring stress sensing applications.

10aFerrite10aMagnetoelastic10aMagnetostriction10aoxide10astress sensing1 aBhame, Shekhar1 aBhapkar, Abhishek1 aShirolkar, Mandar, M.1 aJoy, Pattayil, A. uhttps://library.ncl.res.in/content/magnetostriction-studies-transition-metal-substituted-cobalt-ferrite