The development of noble-metal free electrocatalysts is of high importance for clean energy conversion applications. MoS2 has been considered as a promising low-cost catalyst for the hydrogen evolution reaction (HER), however its activity is limited by poor conductivity and low abundance of active sites.Moreover, its suitability as an effective catalyst for other reactions, in particluar the oxygen reduction reaction (ORR), was hardly explored to date. Herein, we show hybrid nanostructures of shelled CuS particles with MoS2 layers, which produces several outcomes: The MoS2 shell is strained and defective, and charge transfer from the core to MoS2 occurs, enabling activation of the basal plane of MoS2.Changing the feed ratio of the precursors led to control over morphology, such that the wrapping of the cores with the shell was continuously varied and characterized. We found an optimal hybrid structure, which provided high electrochemical active surface area and fast charge transfer kinetics, leading to improved activity not only towards HER (overpotential of 225 mV at 10 mA cm −2 ), but also for the sluggish ORR (onset potential 0.87 V vs RHE).

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Addition of small concentrations of different inorganic salts to THF solutions of poly(3-hexyl thiophene), which contain non-dispersed powder of Multi-Walled Carbon Nanotubes (MWNTs), was found to "salt-in" the precipitated tubes leading to the formation of a stable dispersion of the MWNTs. This effect seems to result from a salt-induced conformational change of polymer chains adsorbed onto the CNTs, resulting in the onset of (entropic) steric repulsion among polymer-decorated chains.