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Highlights: [•] We tried to reduce the dielectric loss and the leakage current of CaCu3Ti4O12 ceramics. [•] CaCu3Ti4O12 powder was coated with the BaTiO3 phase by a sol–gel process. [•] CaCu3Ti4O12 composite samples showed the lowered dielectric losses (<0.05) at ∼10kHz. [•] CaCu3Ti4O12 composite samples showed the reduced leakage currents at the DC field. [•] The BaTiO3 coating is effective to the improvement of their dielectric properties. [Copyright &y& Elsevier]

Highlights: [•] The stability phase diagram of GdBCO was constructed in the PO 2 regime of 1–100mTorr. [•] GdBCO was decomposed into Gd2O3 +Liquid (L1) for 20⩽ PO 2 ⩽100mTorr. [•] GdBCO was decomposed into Gd2O3 +GdBa6Cu3O y (Gd163)+L2 for 1⩽ PO 2 ⩽10mTorr. [•] A monotectic reaction between L1 and L2 +Gd163 occurred for 3⩽ PO 2 ⩽10mTorr. [Copyright &y& Elsevier]

Abstract: Since carbothermal reduction of SnO2 occurs above 600°C, carbon-coating experiments using various polymer precursors have been carried out at relatively low temperatures (∼500°C). It is not likely, however, that the carbon synthesized at ∼500°C much enhances the conductivity of SnO2 anodes, because polymer precursors have undergone insufficient carbonization. This article confirms that the main role of carbon coating is sustaining the domain of each Sn nanoparticle by preventing its aggregation, and thereby improving the cycling performance of SnO2 nanoparticles. The transmission electron microscopy after cycling showing well dispersed Sn nanoparticles and electrochemical impedance spectroscopy revealing larger charge-transfer resistances with increasing carbon contents are in line with these interpretations. [Copyright &y& Elsevier]