TY - JOUR
T1 - Electrochemical properties of (111)-oriented n-Si surfaces derivatized with covalently-attached alkyl chains
AU - Bansal, Ashish
AU - Lewis, Nathan S
PY - 1998/1/1
Y1 - 1998/1/1
N2 - The electrochemical properties of alkyl-terminated, (111)-oriented, n-type Si surfaces, prepared via a two-step halogenation/alkylation procedure, were analyzed in contact with CH3OH-1,1′-dimethylferrocene+/0 (Me2Fc+/0) solutions. Current density-potential and differential capacitance-potential measurements of these surfaces in contact with CH3OH-Me2Fc+/0 indicated that the electrochemical properties of the alkyl-terminated surfaces were very similar to those of the H-terminated Si surface. The alkyl overlayers did not shift the Si band edges or induce significant surface recombination, but they did provide an additional electrical series resistance to charge transfer across the Si/liquid interface. The efficacy of alkyl overlayers in preventing photooxidation and photocorrosion of n-silicon surfaces was measured in contact with CH3OH-Me2Fc+/0 solutions to which a known amount of water had been added. Under these conditions, the alkyl-terminated surfaces consistently showed excellent current density-potential characteristics and displayed lower oxidation rates than the H-terminated surface, indicating that stability toward oxidation had been achieved without any significant compromise in the electrochemical qualities of the silicon surface.
AB - The electrochemical properties of alkyl-terminated, (111)-oriented, n-type Si surfaces, prepared via a two-step halogenation/alkylation procedure, were analyzed in contact with CH3OH-1,1′-dimethylferrocene+/0 (Me2Fc+/0) solutions. Current density-potential and differential capacitance-potential measurements of these surfaces in contact with CH3OH-Me2Fc+/0 indicated that the electrochemical properties of the alkyl-terminated surfaces were very similar to those of the H-terminated Si surface. The alkyl overlayers did not shift the Si band edges or induce significant surface recombination, but they did provide an additional electrical series resistance to charge transfer across the Si/liquid interface. The efficacy of alkyl overlayers in preventing photooxidation and photocorrosion of n-silicon surfaces was measured in contact with CH3OH-Me2Fc+/0 solutions to which a known amount of water had been added. Under these conditions, the alkyl-terminated surfaces consistently showed excellent current density-potential characteristics and displayed lower oxidation rates than the H-terminated surface, indicating that stability toward oxidation had been achieved without any significant compromise in the electrochemical qualities of the silicon surface.
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U2 - 10.1021/jp973118j
DO - 10.1021/jp973118j
M3 - Article
AN - SCOPUS:0032003267
VL - 102
SP - 1067
EP - 1070
JO - Journal of Physical Chemistry B Materials
JF - Journal of Physical Chemistry B Materials
SN - 1520-6106
IS - 7
ER -