Preparation And Characterization Of Mo₂C/CdS As Efficient Cocatalysts For Photocatalytic Hydrogen Evolution

Converting solar energy into hydrogen energy with semiconductor materials is an effective ways to deal with environmental pollution and energy crisis.But due to the limitation of band gap or structure of semiconductor,the photocatalytic activity of semiconductor is not great enough.So,it is essential to modify semiconductor materials.Loading cocatalyst is an effective route to greatly improve photocatalytic activity of semiconductor.Now,most of cocatalysts are noble metals and precious metal compound.Because of the high cost and low storage,it is impossible for industrial appliance.Mo2C has attracted much attention because of its property like Pt.Up to now,Mo2C has not been reported in photocatalysis.This paper prepared Mo2C via a temperature-programmed route with MoO3 as precursor in an atmosphere of H2 and CH4.Then Mo2C/CdS composite photocatalyst was prepared via precipitation.Photocatalysts were characterized with XRD、SEM、TEM、Uv-vis、XPS、BET and Raman.Characterization showed that loading of Mo2C can extend absorption range of CdS and improve the separation of electric and hole without changing the crystal structure of CdS.In the test of photocatalytic activity with GC,the H2 evolution of 2%Mo2C/CdS reached 1610μmol/h·g.It is 10 times of CdS and higher than CdS loading noble metals.The H2 evolution of 2%Mo2C/CdS is 2.3 times of Pt/CdS.Molybdenum carbide can do the same work as platinum,and it is low cost,easy to availability and has potential industrial value.