| Among many renewable energy resources,hydrogen has been regarded as one of the important energy resource for its high fuel value,storable and environmental friendly nature.The method of producing hydrogen that depending on reforming coal and natural gas has aggravated the consumption of non-renewable energy and brought serious environmental pollution problems.It is a new technology to solve the problem of energy and environment pollution by using solar photocatalytic hydrolysis and electrolysis water,and the key is to find a new and efficient catalys.As a rare precious metal material,Pt is the best catalyst with wide commercial application.However,the Pt based materials have limitations of high cost and stability.Therefore,the development of low Pt catalysts with high catalytic performance is the focus of scientific research.Based on this,Fe1-xPtx-ZnCdS nanocomposites were fabricated by loading FePt alloy on ZnCdS nanoparticles in our work,aiming at improving the efficiency of photocatalytic hydrogen production and reduce the amount of Pt;In addition,FePtCu ternary alloy nanoparticles based on the Pt catalyst were prepared,and the effects of composition and high temperature treatment on the structure and the hydrogen production performance of FePtCu were studied,it is possible to design and synthesize a novel Pt based ternary alloy electrocatalysts of stable and efficient for hydrogen production from water electrolysis.Fe1-xPtx-ZnCdS nanocrystals were prepared by ethylene glycol reduction method with ZnCdS solid solution as a semiconductor substrate.Respectively,their morphology,structure and absorption edges,as well as visible light photocatalytic activity were conducted for looking for the best proportion of components,and the electrochemical impedance spectroscopy test was uesed to elaborate the mechanism of Fe1-xPtx alloy influenced on the photocatalytic activity of ZnCdS nanocrystals.The results of X ray diffraction showed that the loading of Fe1-xPtx had no effect on the structure of ZnCdS solid solution.Among a series of Fe1-xPtx-ZnCdS nanoparticles,the H2 evolution rate of 0.5 wt%Fe0.3Pt0.7-ZnCdS(2265 umol g-1h-1)is about 3 times higher than that of pure ZnCdS(740 umol g-1h-1)nanocrystals,which was even better than that of 0.5 wt%Pt-ZnCdS(1626 umol g-1h-1).The polyvinylpyrrolidone（PVP）with different molecular weight serve as surfactant,1,2-hexadecanedio as the reducing agent,dispersed FePtCu ternary alloy nanoparticles were prepared in polyethylene glycol（M=2000）by reducing FeCl2、Pt（acac）2 and Cu（acac）2.The results of X ray diffraction showed that FePtCu nanoparticles with different degree of phase transition could be obtained by changing the K value of PVP and tuning the composition of FePtCu.The effects of different components of Fe PtCu with face centered tetragonal structure on the electrochemical hydrogen evolution（HER）have been studied by electrochemical method.The results show that the Fe:Pt:Cu=4.5:3.5:2.0 is the best molar ratio in the precursor of the reaction,the overpotential of FePtCu nanoparticles at 10 mA/cm2 current density is about 28 mV.FePtCu ternary alloy nanoparticles with different compositions were prepared by reducing metal precursors with Fe（acac）2 as the iron source,oleic acid and oleic acid as surfactant.XRD results showed that FePtCu nanoparticles exhibited a characteristic peak of fct FePt phase after annealing treatment at 550℃,which showed good stability in acidic electrolyte.Electric catalytic characterization results show that the effect of surface organic compounds on the properties of HER was eliminated by high temperature annealing.By adjusting the composition of FePtCu nanoparticles,the HER electrocatalytic properties of FePtCu nanoparticles is better than the commercial Pt/C electrode,and it has a good application foreground in the field of low Pt and high efficiency catalyst for electrolysis of water. |
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