TY - JOUR
T1 - Photoelectrochemical reduction of nitrate on p-Si coated with metallic Re thin films
AU - Muñoz, Eduardo
AU - Schrebler, Ricardo
AU - Henríquez, Rodrigo
AU - Heyser, Cristopher
AU - Verdugo, Patricia A.
AU - Marotti, Ricardo
N1 - Funding Information:
We thank FONDECYT, Chile, for financial support for this study (grant No. 11060514 and 7080186) and the Dirección de Investigación e Innovación of the Pontificia Universidad Católica de Valparaíso (grant No. 037.108/2008 DII-PUCV). E. Muñoz and R. Henríquez thank Programa Bicentenario de Ciencia y Tecnología, PSD82. R. Marotti also acknowledges support received from PEDECIBA — Física, and the CSIC (Comisión Sectorial de Investigación Científica) of the Universidad de la República, in Montevideo, Uruguay. Special thanks to Jennifer A. Kersten of the University of Minnesota for her collaboration on the discussion of this work.
PY - 2009/11/2
Y1 - 2009/11/2
N2 - In this study we examined the rhenium electrodeposition process onto p-Si(100) from acidic media. The study was carried out by means of cyclic voltammetry and the potential-steps method from which the corresponding nucleation and growth mechanism were determined. Both methods were performed under illumination using a solar simulator for electron photogeneration. A 3D progressive nucleation, diffusion-controlled growth of rhenium films was found. Likewise, a morphologic analysis was completed for the deposits obtained at different potential values by means of atomic force microscopy. An energetic characterization through capacitance measurements (Mott-Schottky plots and parallel capacitance) of the p-Si/NO3- and p-Si/Re/NO3- interfaces was done. The photoelectrochemical reduction of nitrate ions, PERN, on the different p-Si/Re electrode systems synthesized was studied. An overpotential decrease of 0.3 V and a photocurrent increase for the PERN on p-Si(100)/Re electrode systems compared with p-Si(100) and metallic Re was found. Finally, the kinetic parameters of the cathodic reactions in the p-Si and p-Si/Re acidic media were estimated using intensity modulated photocurrent spectroscopy. A brief analysis from this technique was done. According to these results, the p-Si/Re electrode system could be a potential photoelectrocatalyst for the PERN.
AB - In this study we examined the rhenium electrodeposition process onto p-Si(100) from acidic media. The study was carried out by means of cyclic voltammetry and the potential-steps method from which the corresponding nucleation and growth mechanism were determined. Both methods were performed under illumination using a solar simulator for electron photogeneration. A 3D progressive nucleation, diffusion-controlled growth of rhenium films was found. Likewise, a morphologic analysis was completed for the deposits obtained at different potential values by means of atomic force microscopy. An energetic characterization through capacitance measurements (Mott-Schottky plots and parallel capacitance) of the p-Si/NO3- and p-Si/Re/NO3- interfaces was done. The photoelectrochemical reduction of nitrate ions, PERN, on the different p-Si/Re electrode systems synthesized was studied. An overpotential decrease of 0.3 V and a photocurrent increase for the PERN on p-Si(100)/Re electrode systems compared with p-Si(100) and metallic Re was found. Finally, the kinetic parameters of the cathodic reactions in the p-Si and p-Si/Re acidic media were estimated using intensity modulated photocurrent spectroscopy. A brief analysis from this technique was done. According to these results, the p-Si/Re electrode system could be a potential photoelectrocatalyst for the PERN.
KW - Electrical properties and measurements
KW - Electrodeposition, silicon
KW - Intensity modulated photocurrent spectroscopy
KW - Nitrate
KW - Photoelectrochemical reduction
KW - Rhenium
UR - http://www.scopus.com/inward/record.url?scp=69549133621&partnerID=8YFLogxK
U2 - 10.1016/j.tsf.2009.06.010
DO - 10.1016/j.tsf.2009.06.010
M3 - Article
AN - SCOPUS:69549133621
SN - 0040-6090
VL - 518
SP - 138
EP - 146
JO - Thin Solid Films
JF - Thin Solid Films
IS - 1
ER -