Abstract
Electrostatic binding of redox-active ions into a polymer-coated electrode is demonstrated to be an effective method of improving photoelectrode stability. Pt and n-type Si electrodes have been coated with poly([4,4′-bipyridinium]-1,1′-diylmethylene-1,2-phenylenemethylene dibromide) (poly-oXV2+) and other viologen-based polymer films. The poly-oXV2+/+· system is insoluble in aqueous solutions containing large anions such as ClO4 -, BF4 -, and Fe(CN)6 4-. Cyclic voltmmetry of modified electrodes in aqueous 1.0 M NaClO4 shows behavior consistent with a reversibly electroactive, surface-confined species, E°′ (poly-oXV2+/+·) = -0.45 V vs. SCE. In the presence of electroactive anions, n-type Si electrodes coated with poly-oXV2+ show substantial improvements in photocurrent stability compared to naked n-Si electrodes. Negative ions from solution are sorbed by the positively charged poly-oXV2+ units, providing efficient scavenging of photogenerated holes at the semiconductor surface. No improvement in stability is observed with positively charged solution ions, such as Fe(H2O)6 2+. Variation in coverage of the polymer coating causes changes in the observed stabilization of photocurrent. The method may provide a useful framework for design of improved coatings for the stabilization of aqueous semiconductor/liquid interfaces.
| Original language | English |
|---|---|
| Pages (from-to) | 3103-3107 |
| Number of pages | 5 |
| Journal | Journal of Physical Chemistry |
| Volume | 88 |
| Issue number | 14 |
| Publication status | Published - 1984 |
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ASJC Scopus subject areas
- Physical and Theoretical Chemistry
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Stabilization of n-type silicon photoanodes in aqueous solution by electrostatic binding of redox ions into charged polymers. / Rosenblum, Mark D.; Lewis, Nathan S.
In: Journal of Physical Chemistry, Vol. 88, No. 14, 1984, p. 3103-3107.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Stabilization of n-type silicon photoanodes in aqueous solution by electrostatic binding of redox ions into charged polymers
AU - Rosenblum, Mark D.
AU - Lewis, Nathan S
PY - 1984
Y1 - 1984
N2 - Electrostatic binding of redox-active ions into a polymer-coated electrode is demonstrated to be an effective method of improving photoelectrode stability. Pt and n-type Si electrodes have been coated with poly([4,4′-bipyridinium]-1,1′-diylmethylene-1,2-phenylenemethylene dibromide) (poly-oXV2+) and other viologen-based polymer films. The poly-oXV2+/+· system is insoluble in aqueous solutions containing large anions such as ClO4 -, BF4 -, and Fe(CN)6 4-. Cyclic voltmmetry of modified electrodes in aqueous 1.0 M NaClO4 shows behavior consistent with a reversibly electroactive, surface-confined species, E°′ (poly-oXV2+/+·) = -0.45 V vs. SCE. In the presence of electroactive anions, n-type Si electrodes coated with poly-oXV2+ show substantial improvements in photocurrent stability compared to naked n-Si electrodes. Negative ions from solution are sorbed by the positively charged poly-oXV2+ units, providing efficient scavenging of photogenerated holes at the semiconductor surface. No improvement in stability is observed with positively charged solution ions, such as Fe(H2O)6 2+. Variation in coverage of the polymer coating causes changes in the observed stabilization of photocurrent. The method may provide a useful framework for design of improved coatings for the stabilization of aqueous semiconductor/liquid interfaces.
AB - Electrostatic binding of redox-active ions into a polymer-coated electrode is demonstrated to be an effective method of improving photoelectrode stability. Pt and n-type Si electrodes have been coated with poly([4,4′-bipyridinium]-1,1′-diylmethylene-1,2-phenylenemethylene dibromide) (poly-oXV2+) and other viologen-based polymer films. The poly-oXV2+/+· system is insoluble in aqueous solutions containing large anions such as ClO4 -, BF4 -, and Fe(CN)6 4-. Cyclic voltmmetry of modified electrodes in aqueous 1.0 M NaClO4 shows behavior consistent with a reversibly electroactive, surface-confined species, E°′ (poly-oXV2+/+·) = -0.45 V vs. SCE. In the presence of electroactive anions, n-type Si electrodes coated with poly-oXV2+ show substantial improvements in photocurrent stability compared to naked n-Si electrodes. Negative ions from solution are sorbed by the positively charged poly-oXV2+ units, providing efficient scavenging of photogenerated holes at the semiconductor surface. No improvement in stability is observed with positively charged solution ions, such as Fe(H2O)6 2+. Variation in coverage of the polymer coating causes changes in the observed stabilization of photocurrent. The method may provide a useful framework for design of improved coatings for the stabilization of aqueous semiconductor/liquid interfaces.
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M3 - Article
VL - 88
SP - 3103
EP - 3107
JO - Journal of Physical Chemistry
JF - Journal of Physical Chemistry
SN - 0022-3654
IS - 14
ER -