Effect of hypophosphite on electrodeposition of graphite@copper powders

摘要

The effect of sodium hypophosphite (NaH2PO2) on the electrodeposition of copper coated graphite powders (graphite@Cu) was investigated in this paper. The cathodic polarization curves were determined by potentiodynamic scanning method in the electrolyte containing various concentrations of NaH2PO2. Hypophosphite could reduce the overpotential of copper deposited on the graphite particles surface and accelerate electroless copper nuclei generated by the reduction reaction. The applied potential promoted the formation of copper nuclei on the surface of graphite powders. Uniform graphite@Cu powders were fabricated by optimizing the NaH2PO2 concentration in the range of 10-15 g dm~(-3). The residue of NaH2_ PO2 could be depleted to less than 0.25 g dm~(-3) by decomposition on the anode and chemical reduction in the bath during electrodeposition. The effect of hypophosphite on the electrodeposition of graphite@Cu is also discussed.