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Polyanthra[1,9,8-b,c,d,e][4,10,5-b,c,d,e]bis-[1,6,6a(6a-S)trithia]pentalene (PABTP) was prepared and investigated as cathode active material for lithium secondary batteries. The organic disulfide polymer was prepared by the direct sulfurization of anthracene and the oxidative coupling polymerization of the sulfide anthracene, characterized by FT-IR, Raman, elemental analysis, XPS and XRD. The polymer was used as cathode active material and the lithium secondary batteries were assembled and tested. The polymer had high specific capacity up to 1500 mAh g −1 , which remained the value of 800 mAh g −1 at the 77th cycle, and kept high charge–discharge efficiency of 85% in the whole test.

This investigation discovers a discrete metallic alloy layer containing Ni, Ti, and Ba between Ni and BaTiO 3 co-fired in reducing atmospheres at ∼1300 °C along with an oxygen-depleted zone in BaTiO 3 adjacent to the metallic layer. Using high-resolution transmission electron microscopy and electron energy-loss spectroscopy, detailed structural and chemical analyses of the metallic layer are carried out. With complementary thermodynamic approximations, these observations render an assessment of the local effective oxygen partial pressure, which is considerably lower than the external, ambient processing environment. Through a set of model experiments on Ni–BaTiO 3 –carbon composites, we illustrate that the presence of carbon is sufficient to reduce locally BaTiO 3 and form the observed metallic layer at ∼1300 °C. A phase stability analysis indicates that the formation of the Ba and Ni–Ti liquid phases provides a kinetic path for the interfacial reaction.

A combination of high-resolution transmission electron microscopy and x-ray photoelectron spectroscopy are used to establish that Ti-B-N films with different boron concentrations prepared by reactive unbalanced magnetron sputtering exhibit a two-phase nanocomposite microstructure, showing nanocrystalline Ti(N, B) grains embedded in amorphous (TiB2, BN) matrices. Using Monte Carlo simulations and based on a simple model employing a kinetic grain growth theory, we also investigate the effects of the amorphous TiB2-BN phase on the microstructure evolution and grain growth in nanocrystalline-Ti(N, B). Our study demonstrates that the formation of such an amorphous phase at the grain boundary could hinder the growth of Ti(N, B) grains and the mean grain size shows an exponential decay with boron concentration, in good agreement with our experimental observations.