TY - JOUR
T1 - Influence of 4-guanidinobutyric acid as coadsorbent in reducing recombination in dye-sensitized solar cells
AU - Zhang, Zhipan
AU - Zakeeruddin, Shaik M.
AU - O'Regan, Brian C.
AU - Humphry-Baker, Robin
AU - Grätzel, Michael
PY - 2005/11/24
Y1 - 2005/11/24
N2 - Dye-sensitized solar cells based on nanocrystalline TiO2 have been fabricated with an amphiphilic ruthenium sensitizer [Ru (4,4′-dicarboxylic acid-2,2′-bipyridine) (4,4′-bis(p- hexyloxystyryl)-2,2′-bipyridine)(NCS)2], coded as K-19, and 4-guanidinobutyric acid (GBA) as coadsorbent. The cells showed a ∼50 mV increase in open-circuit voltage and a similar current in comparison with cells without GBA cografting. The performance of both types of devices was evaluated on the basis of their photocurrent-voltage characteristics, dark current measurements, cyclic voltammetry, electrochemical impedance spectroscopy, and phototransient decay methods. The results indicate that GBA shifted the conduction band of TiO2 toward a more negative potential and reduced the interfacial charge-transfer reaction from conduction band electrons to triiodide in the electrolyte (also known as the back reaction). In addition, the devices with GBA cografting showed an excellent stability with a power conversion efficiency of approximately 8% under simulated full sunlight (air mass 1.5, 100 mW cm-2) during visible light soaking at 60°C.
AB - Dye-sensitized solar cells based on nanocrystalline TiO2 have been fabricated with an amphiphilic ruthenium sensitizer [Ru (4,4′-dicarboxylic acid-2,2′-bipyridine) (4,4′-bis(p- hexyloxystyryl)-2,2′-bipyridine)(NCS)2], coded as K-19, and 4-guanidinobutyric acid (GBA) as coadsorbent. The cells showed a ∼50 mV increase in open-circuit voltage and a similar current in comparison with cells without GBA cografting. The performance of both types of devices was evaluated on the basis of their photocurrent-voltage characteristics, dark current measurements, cyclic voltammetry, electrochemical impedance spectroscopy, and phototransient decay methods. The results indicate that GBA shifted the conduction band of TiO2 toward a more negative potential and reduced the interfacial charge-transfer reaction from conduction band electrons to triiodide in the electrolyte (also known as the back reaction). In addition, the devices with GBA cografting showed an excellent stability with a power conversion efficiency of approximately 8% under simulated full sunlight (air mass 1.5, 100 mW cm-2) during visible light soaking at 60°C.
UR - http://www.scopus.com/inward/record.url?scp=28944442841&partnerID=8YFLogxK
U2 - 10.1021/jp054305h
DO - 10.1021/jp054305h
M3 - Article
AN - SCOPUS:28944442841
SN - 1520-6106
VL - 109
SP - 21818
EP - 21824
JO - Journal of Physical Chemistry B
JF - Journal of Physical Chemistry B
IS - 46
ER -