Study On Photoelectrochemical Performance Of Mo Se2 Films Fabricated By CTAB-assisted Electrodeposition

Molybdenum diselenide?MoSe₂?films,owing to its good absorption coefficient and photoelectrochemical power conversion efficiency in the ultraviolet and visible light band,have been applied to solar photoelectrochemical cells.It is important to fabricate MoSe₂films with excellent photoelectrochemical performance by low-cost and large-area production for solar energy conversion.In this work,MoSe₂ films were fabricated by the surfactant CTAB-assisted electrodeposition.Improvement of photoelectrochemical performance was achieved by annealing in air while a layer of semiconductor oxide MoO₃was prepared on MoSe₂ films.The influence of CTAB concentration on the photoelectrochemical performance of MoSe₂ films was studied and the corresponding mechanism was analyzed.The results are as follows:The effects of different types of surfactants,such as DTAB,SDS and Triton X-100,on the photoelectrochemical performance of MoSe₂ films were investigated,and the corresponding mechanisms of electrodeposition using different type of surfactants were analyzed.The SDS and Triton X-100 slowed down nucleation and growth rate of the film.However,the DTAB accelerated nucleation and growth rate of the film,thus a film with less hole-defects was formed,which can improve the photoelectrochemical performance of the films.Furthermore,the effects of surfactants DTAC and CTAB on the photoelectrochemical performance of MoSe₂ films were discussed.It is found that the CTAB was the best surfactant among the 3 candidates to improve the photoelectrochemical performance of MoSe₂ films.Finally,the influence of CTAB concentration on the photoelectrochemical performance of MoSe₂ films was researched.The result indicated that the concentration of CTAB in the electrolyte affected both the nucleation rate and growth rate of MoSe₂ films during electrodeposition.The photocurrent density of MoSe₂ films increased initially and then decreased with the increasing of CTAB concentration.When the concentration of CTAB was 5.5 mmol dm^-3,the photocurrent density(J_sc)of the MoSe₂ films reached 2.1 mA cm^-2at zero bias which was an order of magnitude higher than the methods reported in the literatures.The enhancement of photoelectrochemical performance of MoSe₂ films can be attributed to the good light-absorbing property,high conductivity,and carrier density.