Visible-to-Near-IR Wide-Range Light Harvesting by Interfacial Charge-Transfer Transitions between TiO2 and p-Aminophenol and Evidence of Direct Electron Injection to the Conduction Band of TiO2

Interfacial charge-transfer (ICT) transitions involved in charge-separation mechanisms are expected to enable efficient photovoltaic conversions through one-step charge-separation processes. With this in mind, the charge-transfer complex fabricated from TiO2 nanoparticles and 7,7,8,8-tetracyanoquinodimethane (TCNQ) has been applied to dye-sensitized solar cells. However, rapid carrier recombination from the conduction band of TiO2 to the highest occupied molecular orbital (HOMO) of TCNQ remains a major issue for this complex. In this study, to inhibit surface-complex recombinations, we prepared Nb-doped TiO2 nanoparticles with different atomic ratios for enhanced electron transport. To investigate the effects of doping on electron injection through ICT transitions, these materials were examined as photoelectrodes. When TiO2 was doped with 1.5 mol % Nb, the Fermi level of the TiO2 electrode shifted toward the conduction band minimum, which improved electron back-contact toward the HOMO of TCNQ. The enhancement in electron transport led to increases in both short circuit current and open circuit voltage, resulting in a slight (1.1% to 1.3%) improvement in photovoltaic conversion efficiency compared to undoped TiO2. Such control of electron transport within the photoelectrode is attributed to improvements in electron injection through ICT transitions.

Download Full-text

Theoretical Study on Interfacial Charge Transfer Transitions of the Surface Complex between TiO2 and TCNTQ

ECS Meeting Abstracts ◽

10.1149/ma2013-01/38/1321 ◽

2013 ◽

Keyword(s):

Charge Transfer ◽

Theoretical Study ◽

Surface Complex ◽

Interfacial Charge Transfer ◽

Charge Transfer Transitions ◽

Interfacial Charge

Download Full-text

Interfacial charge-transfer transitions in a TiO2-benzenedithiol complex with Ti–S–C linkages

Physical Chemistry Chemical Physics ◽

10.1039/c5cp05046d ◽

2015 ◽

Vol 17 (44) ◽

pp. 29867-29873 ◽

Cited By ~ 15

Author(s):

Jun-ichi Fujisawa ◽

Ryuki Muroga ◽

Minoru Hanaya

Keyword(s):

Charge Transfer ◽

Visible Light ◽

Room Temperature ◽

Light Response ◽

Interfacial Charge Transfer ◽

Visible Light Response ◽

Charge Transfer Transitions ◽

Interfacial Charge

A visible light response of TiO2 due to interfacial charge-transfer transitions was obtained by the addition of benzenedithiol at room temperature.

Download Full-text

Facile interfacial charge transfer across hole doped cobalt-based MOFs/TiO2 nano-hybrids making MOFs light harvesting active layers in solar cells

Journal of Materials Chemistry A ◽

10.1039/c5ta07180a ◽

2015 ◽

Vol 3 (45) ◽

pp. 22669-22676 ◽

Cited By ~ 43

Author(s):

Deok Yeon Lee ◽

Iseul Lim ◽

Chan Yong Shin ◽

Supriya A. Patil ◽

Wonjoo Lee ◽

...

Keyword(s):

Solar Cells ◽

Charge Transfer ◽

Solar Radiation ◽

Light Harvesting ◽

Hole Doping ◽

Interfacial Charge Transfer ◽

Active Layers ◽

Interfacial Charge

Hole doping leads to an efficient photo-induced interfacial charge transfer from MOFs to TiO2 and thereby the MOFs can harvest solar radiation to generate electricity.

Download Full-text