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Rhombohedral shaped MnCO 3 and its hybrid composite with in situ reduced graphene oxide (rGO) and multiwalled carbon nanotubes (MWCNT) have been synthesized by a simple and cost effective hydrothermal approach and examined as active material for supercapacitor application. The redox active MnCO 3 showed high specific capacitance of 185 F/g at 1.5 A/g in 1 M Na 2 SO 4 electrolyte accompanied by high cycle stability. The high utility of the pseudocapacitive MnCO 3 was achieved in its carbonaceous materials based hybrid composites exhibiting the maximum specific capacitance of 368 F/g and 357 F/g, respectively for the rGO-MnCO 3 and MWCNT-MnCO 3 composite at 1.5 A/g current accompanied by very high cycle efficiency of 96% and 97% specific capacitance retention over 1000 charge discharge cycle at 3 A/g. The high surface activity of the MnCO 3 along with the synergistic effect with highly conductive and high surface area porous rGO and MWCNT resulted in their high energy density of 51.11 Wh/kg and 49.58 Wh/kg, respectively at a power delivery rate of 750 W/kg suggesting both of them are competent to act as supercapacitor electrode material. [ABSTRACT FROM AUTHOR]

Highlights: [•] H+, Fe3+ codoped Polyaniline/MWCNTs nanocomposite was prepared by in situ oxidative polymerization. [•] The formation of the nanocomposite was confirmed by FTIR, Raman, XRD, FESEM and TEM analyses. [•] Electrochemical behavior was studied by a three electrode system in 1M H2SO4 electrolyte. [•] The nanocomposite exhibited highest specific capacitance of 575F/g at 1A/g current density. [ABSTRACT FROM AUTHOR]

Highlights: [•] Ni(OH)2, Ag deposited Ni(OH)2 and their composites with graphene were synthesized. [•] XRD, FESEM and TEM analyses confirmed the formation of the composites. [•] Ag deposition increases the pseudocapacitive utility of Ni(OH)2. [•] Ag@Ni(OH)2/graphene composite exhibited the best electrochemical behavior. [•] Ag@Ni(OH)2/graphene exhibited 496F/g specific capacitance at 1A/g current density. [Copyright &y& Elsevier]

• Syntheses and structural characterization of group 9 triple decker sandwich complexes comprising a planar 5-membered middle-deck with coinage metal. • Density functional theory calculations provided a well-defined picture about the bonding of these heterometallic triple decker complexes. • The experimental results have been accompanied and rationalized using DFT studies. Earlier accounts of triple-decker complexes comprising main group elements and transition metals in the middle-deck, motivated us to synthesize triple-decker complexes containing coinage metals in the middle-deck. As a result, we have explored the reactivity of open-cage nido ‑ [(Cp*M) 2 { μ -B 2 H 2 E 2 }], 1 – 3 (Cp* = η 5-C 5 Me 5 , 1 : M = Co, E = S ; 2 : M = Co, E = Se; 3 : M = Rh, E = Se) with [CuBr(SMe 2)]. All the reactions yielded triple-decker complexes, [(Cp*M) 2 { μ -B 2 H 2 E 2 CuBr}], 4 – 6 (4 : M = Co, E = S ; 5 : M = Co, E = Se; 6 : M = Rh, E = Se) having [CuBr] in the middle-deck. The removal of the SMe 2 ligand resulted in the formation of complexes 4 – 6 as a single product. These complexes are examples of triple-decker species having a planar 5-membered [B 2 E 2 Cu] (E = S or Se) middle deck, in which the Cu exists as Cu(I) with an elongated M-Cu bonding interaction. Synthesized complexes have been established by ESI-MS, multinuclear nuclear magnetic resonance (NMR), and IR spectroscopy. The solid-state structures of 5 and 6 were confirmed by single-crystal X-ray diffraction analyses. Density functional theory (DFT) analyses of these complexes have presented a high electron donation from the [B 2 E 2 ] (E = S or Se) fragment of the middle ring to the axial metals and a weak bonding interaction between group 9 metals and Cu. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: The present research work demonstrated the reinforcing effect of expanded graphite (EG) and modified EG (MEG) with and without carbon black (CB) on the physical, mechanical and thermo-mechanical properties of emulsion polymerized styrene butadiene rubber (SBR) vulcanizates. In separate batches, EG and MEG flakes with and without CB were incorporated into the SBR by melt blending. The microstructures of the nanocomposites were precisely characterized by wide angle X-ray diffraction (WAXD) analysis and high resolution transmission electron microscope (HR-TEM). EG and MEG filled SBR compounds showed improvement in the curing features, mechanical, thermal and dynamic mechanical properties than their respective controls. [Copyright &y& Elsevier]