Synthesis and electrochemical characterization of sponge-like nickel nanoparticles

Nickel and its alloys are the most studied electrode materials. Nickel exhibits a high initial electrocatalytic activity in the hydrogen evolution reaction (HER). Enhancement of cathodic activity of nickel for HER has been carried out by the formation of nanostructured nickel materials. In this context, the use of an organometallic precursor, able to decompose in mild conditions in the presence of a reducing gas has arisen as a suitable method of synthesis of these species. In this work, we investigated the synthesis of nickel nanoparticles starting from Ni(COD)2, (COD=cycloocta-1,5-diene) and decomposed under H2 atmosphere in THF in presence of 1,3diaminopropane as stabilizer. TEM studies revealed the formation of characteristic particles resulting from the agglomeration of initially obtained nanocrystallites. The activity of the dispersed catalysts composed of Ni/C with respect to the HER was investigated using steady state polarization measurements.