Photoelectrochemical(PEC)water splitting technique is considered as a promising and effective method for converting solar energy into hydrogen energy.In recent years,antimony sulfide(Sb2S3),as a non-toxic and environmentally friendly material with abundant reserves on the earth,has come into people’s attention.Meanwhile,due to its narrow band gap semiconductor belonging to theⅤ-Ⅵgroup,it has an appropriate band gap width close to the maximum value of solar spectrum and a high light absorption coefficient(α≈1.8×105cm-1,λ=450 nm),which has attracted extensive attention in the field of PEC water splitting.However,the serious carrier recombination problem caused by the internal defects of Sb2S3semiconductor limits its further application.Meanwhile,the high photocorrosivity of Sb2S3also affects the stability of the photoelectrode.In this paper,based on the prepared p-type Sb2S3,the stability and carrier separation efficiency of Sb2S3were improved through the construction of heterojunction and the loading of cocatalyst,and relatively considerable PEC water splitting performance was obtained.The specific research contents are as follows:(1)A p-type Sb2S3semiconductor was prepared on ITO substrate by one-step hydrothermal method.The morphology and optical absorption capacity of Sb2S3were studied before and after high temperature annealing.Meanwhile,the photoelectrochemical properties of Sb2S3were tested from photocathode and photoanode directions,respectively.The experimental results showed that Sb2S3after high temperature annealing had a more dense surface morphology,its light absorption capacity and photocurrent density had been significantly improved.(2)The Sb2S3/Sn S2heterojunction was constructed by microwave solvothermal method for the first time by regulating the reaction time and temperature,and Fe OOH particles were introduced by solution soaking method.The results show that the maximum transient photocurrent density is 2.65 m A/cm2,5.3 times than that of Sb2S3.During the one-hour stability test,the photocurrent density of the Sb2S3/Sn S2/Fe OOH composite photoelectrode showed no significant attenuation.It is concluded that the construction of Sb2S3/Sn S2heterojunction and the loading of Fe OOH particles accelerate the separation of carriers on the surface of Sb2S3and improve the stability of the photoelectrode.(3)The Sb2S3/In2S3direct Z-scheme heterojunction was constructed,which effectively solved the charge recombination problem caused by defects near the valence band of Sb2S3and improved the charge separation efficiency.The experimental results showed that Sb2S3/In2S3heterojunction has higher separation efficiency and injection efficiency.At 1.23 V vs.RHE,the maximum photocurrent density was 1.24 m A/cm2,5.6 times than that of the Sb2S3(0.22 m A/cm2).In addition,Sb2S3/In2S3direct Z-scheme heterojunction had an earlier onset potential(about 0.7 V vs.RHE),which was about 0.3 V higher than the Sb2S3.This work provides a new idea for the application of antimony sulfide compounds in the field of PEC water splitting. |