KOREA-USA Nanoforum
CdS or CdSe Decorated TiO2 Nanotube
Arrays from Spray Pyrrolysis Deposition:
U iin Ph
Use
Photoelectrochemical
l
h i lC
Cells
ll
Sungkyunkwan University
Jong Hyeok Park
Solar Resource
165,000 TW of Sunlight hit the earth
Additional Energy about 30 TW
should
h ld be
b produced
d
d until
til 2050
One of Possible Strategies:
Solar Energy
Energy Conversion Strategies
Energy Conversion Strategies
Fuel
Light
Electricity
Fuels
CO2
Electricity
O2
H2
e
Sugar
M
SC
H2O
O2
Photosynthesis
e
SC
M
H2O
Semiconductor / Liquid
Junctions
Photovoltaics
Nanostructured Materials
Nano Lett. 6, 24 (2006).
J. Mater. Chem. 20, 2247 (2010).
Appl. Phys. Lett. 89, 163106 (2006)
Chem. Comm. 2867 (2008).
Chem. Comm. 2385 (2010).
ACS Appl. Mater. & Inter. 2, 288 (2010).
In My Poster: QDs Coated TiO2 NTs
CdS or CdSe precursor solution
CdS or CdSe
TiO2 NT
Ti foil
Hot Plate (~450oC)
Spray Pyrolysis Method:
1. Simple
2. Suitable for large area coating
3. Precursor solution spray during
thermal annealing of substrates
Analysis of Mechanism:
High Current Density
11
ْ
⊖
ْ
⊖
ْ
Q.D
⊖
TiO2 NT
⊖
ْ
Q.D
Q
⊖
Photocurrent (mA/cm
m2)
⊖
10
9
8
3μmTiO2NTs
CdSe/3μm
CdS/0.4μm
CdSe/0 4μm
CdSe/0.4
7
6
5
4
3
2
1
TiO2 NT
0
-1.0
Aqueous solution: 0.35 M Na2SO3 + 0.24 M Na2S.
-0.8
-0.6
-0.4
-0.2
0.0
Potential (V) vs Ag/AgCl
10
Efficienc
cy (%)
8
6
4
2
η(%)
( ) = [[Jp × (1.23
(
– Eapp)]/P
)]/ light]
0
-1.2
-1.0
-0.8
-0.6
-0.4
-0.2
Potential (V vs. Ag/AgCl)
0.0
0.2
Length= 600nm
Length=1500nm
CdS NPs coupled TiO2 NRs - SPD
0.1M thiourea
0.1M CdCl2
CdS nanoparticle
TiO2 nanorod
FTO glass
Hot plate(450℃)
CdS NPs coupled TiO2 NRs - SPD
Unassisted Water Splitting
Pt
Dye-coated TiO2
N-type
N
type SC
e-
I3eI-
Dye
h+
eh-+
eTiO2
2H+ + 2e- → H2
N-type SC
eh-+
H2O + 2h+ → 2H+ + 1/2O2
Ti-foil or SUS foil
See You at Poster Session