PMID- 20136125
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20100602
LR  - 20100224
IS  - 1520-5126 (Electronic)
IS  - 0002-7863 (Linking)
VI  - 132
IP  - 8
DP  - 2010 Mar 3
TI  - Photoelectrochemical processes in polymer-tethered CdSe nanocrystals.
PG  - 2622-32
LID - 10.1021/ja907782f [doi]
AB  - We demonstrate the electrochemical capture of CdSe semiconductor nanocrystals 
      (NCs), with thiophene-terminated carboxylic acid capping ligands, at the surfaces 
      of electrodeposited poly(thiophene) films (i) 
      poly((diethyl)propylenedixoythiophene), P(Et)(2)ProDOT; (ii) 
      poly(propylenedioxythiophene), PProDOT; and (iii) poly(ethylenedioxythiophene), 
      PEDOT, coupled with the exploration of their photoelectrochemical properties. 
      Host polymer films were created using a kinetically controlled electrodeposition 
      protocol on activated indium-tin oxide electrodes (ITO), producing conformal 
      films that facilitate high rates of electron transfer. ProDOT-terminated, 
      ligand-capped CdSe-NCs were captured at the outer surface of the host polymer 
      films using a unique pulse-potential step electrodeposition protocol, providing 
      for nearly close-packed monolayers of the NCs at the host polymer/solution 
      interface. These polymer-confined CdSe NCs were used as sensitizers in the 
      photoelectrochemical reduction of methyl viologen (MV(+2)). High internal quantum 
      efficiencies (IQEs) are estimated for photoelectrochemical sensitized MV(+2) 
      reduction using CdSe NCs ranging from 3.1 to 7.0 nm diameters. Cathodic 
      photocurrent at high MV(+2) concentrations are limited by the rate of 
      hole-capture by the host polymer from photoexcited NCs. The rate of this 
      hole-capture process is determined by (a) the onset potential for reductive 
      dedoping of the host polymer film; (b) the concentration ratio of neutral to 
      oxidized forms of the host polymer ([P(n)]/[P(ox)]); and (c) the NC diameter, 
      which controls its valence band energy, E(VB). These relationships are consistent 
      with control of photoinduced electron transfer by Marcus-like excess free energy 
      relationships. Our electrochemical assembly methods provide an enabling route to 
      the capture of functional NCs in conducting polymer hosts in both 
      photoelectrochemical and photovoltaic energy conversion systems.
FAU - Shallcross, R Clayton
AU  - Shallcross RC
AD  - Department of Chemistry, University of Arizona, Tucson, Arizona 85721, USA.
FAU - D'Ambruoso, Gemma D
AU  - D'Ambruoso GD
FAU - Pyun, Jeffrey
AU  - Pyun J
FAU - Armstrong, Neal R
AU  - Armstrong NR
LA  - eng
PT  - Journal Article
PL  - United States
TA  - J Am Chem Soc
JT  - Journal of the American Chemical Society
JID - 7503056
EDAT- 2010/02/09 06:00
MHDA- 2010/02/09 06:01
CRDT- 2010/02/09 06:00
PHST- 2010/02/09 06:00 [entrez]
PHST- 2010/02/09 06:00 [pubmed]
PHST- 2010/02/09 06:01 [medline]
AID - 10.1021/ja907782f [doi]
PST - ppublish
SO  - J Am Chem Soc. 2010 Mar 3;132(8):2622-32. doi: 10.1021/ja907782f.