Hybrid of NiO-Ni12P5/N-doped carbon nanotubes as non-noble electrocatalyst for efficient hydrogen evolution reaction

Abstract

Nickel oxide and nickel phosphide supported by nitrogen-doped multi-walled carbon nanotubes (NiO-Ni12P5/NCNTs) nanocomposites were reported as non-noble metal hybrid electrocatalysts for hydrogen evolution reaction (HER). First, an amorphous nickel phosphorous coating was facilely formed on the surface of pristine CNTs (aNi-P/CNTs) through a simplified electroless deposition without the pretreatment steps of purification, sensitization and activation. Then, aNi-P/CNTs were heated with melamine at 600 °C for 1 h under an Ar atmosphere to prepare NiO-Ni12P5/NCNTs. The as-fabricated NiO-Ni12P5/NCNTs electrocatalysts showed high HER electrocatalytic activity of -0.17 V at 10 mA cm−2, a Tafel slope of 75 mV dec-1 and a high exchange current density of 0.049 mA cm-2. Moreover, the NiO-Ni12P5/NCNTs electrocatalysts showed a much higher durability than Pt/C after the accelerated durability tests in 0.1 M KOH. The NiO-Ni12P5/NCNTs electrocatalysts displayed good activity and stability for HER, which may originate from the synergistic effect between the Ni compound and NCNTs.