This work investigated the influence of silver plasmon and reduced graphene oxide(r GO)on the photoelectrochemical performance(PEC)of Zn O thin films synthesized by the sol-gel method.The physicochemical properties of...This work investigated the influence of silver plasmon and reduced graphene oxide(r GO)on the photoelectrochemical performance(PEC)of Zn O thin films synthesized by the sol-gel method.The physicochemical properties of the obtained photo-anodes were systematically studied by using several characterization techniques.The x-ray diffraction analysis showed that all samples presented hexagonal wurtzite structure with a polycrystalline nature.Raman and energy dispersive x-ray(EDX)studies confirmed the existence of both Ag and r GO in Zn O:Ag/r GO thin films.The estimated grain size obtained from scanning electron microscopy(SEM)analysis decreased with Ag doping,then increased to a maximum value after r GO addition.The UV-vis transmission spectra of the as-prepared Zn O:Ag and Zn O:Ag/r GO thin films have shown a reduction in the visible range with a redshift at the absorption edges.The bandgaps were estimated to be around 3.17 e V,2.7 e V,and 2.52 e V for Zn O,Zn O:Ag,and Zn O:Ag/r GO,respectively.Moreover,the electrical measurements revealed that the charge exchange processes were enhanced at the Zn O:Ag/r GO/electrolyte interface,accompanied by an increase in the(PEC)performance compared to Zn O and Zn O:Ag photo-anodes.Consequently,the photocurrent density of Zn O:Ag/r GO(0.2 m A·cm^(-2)) was around 4 and 2.22 times higher than photo-anodes based on undoped Zn O(0.05 m A·cm^(-2)) and Zn O:Ag(0.09 m A·cm^(-2)),respectively.Finally,from the flat band potential and donor density,deduced from the Mott-Schottky,it was clear that all the samples were n-type semiconductors with the highest carrier density for the Zn O:Ag/r GO photo-anode.展开更多
基金funded by Tunisian Ministry of Higher Education and Scientific Research through the budget allowed to the implied Tunisian labs。
文摘This work investigated the influence of silver plasmon and reduced graphene oxide(r GO)on the photoelectrochemical performance(PEC)of Zn O thin films synthesized by the sol-gel method.The physicochemical properties of the obtained photo-anodes were systematically studied by using several characterization techniques.The x-ray diffraction analysis showed that all samples presented hexagonal wurtzite structure with a polycrystalline nature.Raman and energy dispersive x-ray(EDX)studies confirmed the existence of both Ag and r GO in Zn O:Ag/r GO thin films.The estimated grain size obtained from scanning electron microscopy(SEM)analysis decreased with Ag doping,then increased to a maximum value after r GO addition.The UV-vis transmission spectra of the as-prepared Zn O:Ag and Zn O:Ag/r GO thin films have shown a reduction in the visible range with a redshift at the absorption edges.The bandgaps were estimated to be around 3.17 e V,2.7 e V,and 2.52 e V for Zn O,Zn O:Ag,and Zn O:Ag/r GO,respectively.Moreover,the electrical measurements revealed that the charge exchange processes were enhanced at the Zn O:Ag/r GO/electrolyte interface,accompanied by an increase in the(PEC)performance compared to Zn O and Zn O:Ag photo-anodes.Consequently,the photocurrent density of Zn O:Ag/r GO(0.2 m A·cm^(-2)) was around 4 and 2.22 times higher than photo-anodes based on undoped Zn O(0.05 m A·cm^(-2)) and Zn O:Ag(0.09 m A·cm^(-2)),respectively.Finally,from the flat band potential and donor density,deduced from the Mott-Schottky,it was clear that all the samples were n-type semiconductors with the highest carrier density for the Zn O:Ag/r GO photo-anode.
