The Research Of Photocatalytic Hydrogen Generation Based On Supported Composite Sulfide And Rh Quantum Dots Catalysts

In this paper,the performances of photocatalytic hydrogen generation of composite sulfides and Rh quantum dots cocatalyst supported on MIL-101 and three-dimensional graphene were studied.The effects of the crystal structure and the topology of carrier on the catalytic activity were discussed in detail,and achieved the following innovative results:1.Study on Photocatalytic Hydrogen Generation of Co₂Ni₂S₄@MIL-101 Composite Catalyst with Low Hydrogen Adsorption EnergyThe hydrogen adsorption energy of different crystal planes on Co₂Ni₂S₄ catalyst was obtained by DFT and FMOT calculations,which the?200?plane owned the lowest energy.Then,Co₂Ni₂S₄@MIL-101 composite catalyst with different crystal planes supported on MIL-101 was obtained by preparative chemistry.After detailed photocatalytic hydrogen generation research,it was confirmed that the cocatalyst with the?200?facet had the lowest overpotential,which also showed the best catalytic activity.Based on the experimental results,it was found that Co₂Ni₂S₄ nanoparticles anchored on the MIL-101 had the most favorable surface structure of the catalytic reaction,which was conducive to the rapid transfer of photogenerated electrons.Under the visible light irradiation,the hydrogen production rate of Co₂Ni₂S₄@MIL-101 with the?200?plane was 882.7 ?mol/120 min,and the corresponding apparent quantum efficiency was 48.9%?430 nm?.The catalyst also had the largest photocurrent,the lowest hydrogen evolution overpotential?-0.33V?and the longest fluorescence lifetime?1.49 ns?.2.Study on photocatalytic hydrogen evolution of Rh quantum dots loaded on 3D graphene as the cocatalyst under visible light irradiationTaking advantage of the two-dimensional graphene's flexible properties,we constructed the 3D graphene with topological structure,and loaded the Rh QDs on it to prepare the Rh QDs/3DGR catalyst that was used to study the photocatalytic hydrogen production reaction.The topological structure of 3D graphene could eliminate anisotropy of electrons and promoted the electrons transfer in the graphene layers,which could improve the electron transfer rate and make the catalyst show high activity and stability.The amount of H2 reached 794.2 ?mol in 120 min over EY-sensitized Rh/3DGR catalyst,and AQEs is 12.6 %?520 nm?.In addition,the Rh/3DGR catalyst showed a largest transient photocurrent,lowest overpotential?-0.35V?and longest fluorescence lifetime?1.37 ns?.