Synthesis And Catalytic Performance Of Transition Metal Nickel (Iron) Phosphide

Transition metal phosphide materials have lots of application fields,such as catalysis,magnetism,ceramics materials,light,electronics and so on.It is generally considered to be a novel green and potential catalyst.In this paper,we successfully synthesized a cheap phosphide material by pyrolysis sodium hypophosphite and nickel sources.The morphologies and structure of these materials were studied and their catalytic performances in electrochemical water splitting,activating monosulfate to degrade organic dyes and reduction of 4–nitrophenol were tested.The main research contents are as follows:A series of Nix Fe2-xP?x = 2,1.5,1.0,0.5,0?was prepared by pyrolysis nickel iron oxalate with sodium hypophosphite.We tested their OER electrocatalytic performance in alkaline conditions,which indicated that the Ni-Fe phosphide solid solution showed better electrocatalytic activity than Ni₂P and Fe2 P.The Ni1.5Fe0.5P cluster nanosheets exhibits the best electrocatalytic activity.The Ni1.5Fe0.5P exhibited excellent electrocatalytic properties for oxygen evolution with a low onset overpotential of 285 mV at a current density of 10 mA cm-2 and a small Tafel slope of 51.9 mV dec-1 in 1M KOH.Galvanostatic data indicated the superior stability of the Ni1.5Fe0.5P.The catalytic performance of Ni₂P in oxidative peroxymonosulfate?PMS?to degradation of MB in water was investigated.The results showed that the Ni₂P/PMS system has a better catalytic effect than single Ni₂P or PMS,confirmed that Ni₂P can catalyze PMS.It was found that the degradation rate of MB improved by increasing the amount of Ni₂P or PMS.The use of 150 mg L-1 Ni₂P and PMS formed a nearly complete removal of MB?100 mg L-1?in short time at 30?.The MeOH and TBA reagents was used as free radical quencher,it was proved that the main active radical in this system was SO4·–.According to the Arrhenius equation,the activation energy of Ni₂P/PMS system is 37 kJ/mol,which is lower than other reported in the literature.Ni₂P showed stable catalytic performance and high recovery rate in cyclic experiments.The Ni₂P catalyst can be prepared by reducing nickel iron oxalate with sodium hypophosphite.We analyzed the phase,morphology and composition by XRD,SEM,EDS,TEM and XPS.We studied the effect of Ni₂P catalyst reduction 4-NP.Ni₂P nanoparticles with a diameter of 20 100 nm have very good catalytic reduction performance and a large reaction rate constant of 1.0343 min-1.The cyclic experiment of the catalyst showed that the Ni₂P has good reuse stability.The same experimental method proved that Ni₂P also had good catalytic effect and cycling stability for the catalytic reduction of the rhodamine B.