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A mixture of graphene/graphite as new support was prepared by ball milling procedure and was used for Nickel nanoparticles supported that was employed as a cathode catalyst for hydrogen evolution reaction (HER) in the KOH solution. The structure and electrocatalytic activity of electrocatalyst were investigated by Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD) analysis, and electrochemical techniques. The results indicated that by raising the time of the ball milling from 0 to 270 min, the HER activity of electrocatalyst first increased, and then decreased according to the increase of active sites and then agglomeration of Ni nanoparticles. Ni nanoparticles supported on the mixture with 180 min ball milling exhibited the highest HER activity with a low overpotential (205 mV at 10 mA cm−2), Tafel slope of 84 mV dec−1, and remarkable durability.

Ni foam was modified by a catalyst with low content of Pd, Ni, Fe and Co metal nanoparticles (PdNiFeCo/C-Ceria-NF) and evaluated as the cathode in alkaline anion exchange membrane (AAEM) water electrolyzer. The electrochemical activity of the electrode in hydrogen evolution reaction (HER) was investigated using cyclic voltammetry (CV) and Linear Sweep Voltammetry (LSV) techniques. The performance of catalyst as the cathode was investigated in an AAEM electrolyzer single cell by separating of the anode and cathode polarizations. PdNiFeCo/C-Ceria-NF exhibited a high catalytic activity toward HER and AAEM cathode reaction. PdNiFeCo/C-Ceria-NF showed a low Tafel slope (−79 mV dec−1), and low overpotential at the current density of 10 mA cm−2 (−14 mV) in HER. Also, PdNiFeCo/C-Ceria-NF electrode showed an excellent stability performance in alkaline media during 30 h. The membrane electrode assembly (MEA) which was equipped with PdNiFeCo/C-Ceria-NF exhibited the cell voltage of 2.31 V compared to 2.22 V for Pt/C on Ni foam (Pt/C NF) at the current density of 300 mA cm−2.

A new, convenient and high yielding procedure for the preparation of diethyl α-aminophosphonates in water by one-pot reaction of aldehydes, amines, tri/dialkyl phosphites in the presence of a low catalytic amount of [Cu(3,4-tmtppa)](MeSO 4 ) 4 (0.16 mol%) as a highly stable and re-usable catalyst is described.

An efficient method for the synthesis of secondary and primary dialkyl α-aminophosphonates under solvent-free conditions by one-pot reaction of aldehydes/ketones, amines/ammonium acetate and trialkyl/diethyl phosphite in the presence of a low catalytic amount of [ Cu (3,4-tmtppa)]( MeSO 4)4(0.16 mol%) as a highly stable and reusable catalyst, is described. By this method, aromatic, aliphatic, cyclic and heterocyclic aldehydes, hindered and cage ketones are converted into their corresponding α-aminophosphonates in good to excellent yields.

A new, convenient and high yielding procedure for the preparation of diethyl α-aminophosphonates in water by one-pot reaction of aldehydes, amines, tri/dialkyl phosphites in the presence of a low catalytic amount of [Cu(3,4-tmtppa)](MeSO 4 ) 4 (0.16 mol%) as a highly stable and re-usable catalyst is described.