Jian Xu, Ning ZhaoNational Laboratory of Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences
Superhydrophoic and Superhydrophoic and
suphydrophilic surfacesuphydrophilic surface
-- Its Its architecturearchitecture and applications and applications
Outline
1.Background
2.Our Work
Transparent superhydrophilic and Ultra-hydrophobic
coatings with anti-fogging & anti-reflective properties
3. Application:
Performance of AR coating on solar cell
4. Conclusion
Background
Surface wettabilitySurface wettability
Cell adhesion and growth
Catalyzing
Waterproof
Oil extraction
Lubrication
Self-cleaning
173.0o±2.5
o
Surfaces with a special wettabilitySurfaces with a special wettability
Superhydrophobic surface with lotus effect Superhydrophilic surface with anti-fogging property
Gradient wettability
Response to Electrical Potential
Surface with a reversible wettability responsive to external stimuli
Macromol. Rapid Commun. 2004, 25, 1606 Nano Letters 2006, 6, 2305
Langmuir 2004, 20, 5952 Science 2003, 299, 371
Previous work: Previous work: superhydrophobic polymeric coatingssuperhydrophobic polymeric coatings
PMMA PS
PS-b-PDMSPP-b-PMMA
PC
Macromolecules,Macromolecules, 2005, 2005, 38, 38, 8996. 8996.
Adv. Mater.Adv. Mater., 2004, 16, 302; 16, 1830., 2004, 16, 302; 16, 1830.
Macromol. Rapid Commun., 2005, 26, 1075
ChemPhysChem, 2007, 8,1108; 7, 8247, 824
Experimental route design
After step 1 After step 2
Nanoparticle preparation
With a diameter of 30nm
LBLfilm UV+ O3
1 2
Superhydrophilic film with
antifogging property
The profile image of water droplet on the surface
Previous work: Previous work: superhydrophilic inorganic-organic hybrid coatingssuperhydrophilic inorganic-organic hybrid coatings
The profile image of water droplet on the surface
Characterization of superhydrophilic surface Characterization of superhydrophilic surface
Outline
1.Background
2.Our Work2.Our Work
Transparent superhydrophilic and Ultra-hydrophobic
coatings with anti-fogging & anti-reflective properties
3. Application:
Performance of AR coating on solar cell
4. Conclusion
Surface morphology of the transparent filmSurface morphology of the transparent film
SEM image AFM image
Inorganic and organic hybrids film with nanostructure
Hydrophobic modification with different silanes
146.5±2.3 147.2±1.3 149.0±1.6 153.6±2.6
CTMS ODMCS OTDDMCS TDF-DMCS
Superhydrophobic & transparent coatingSuperhydrophobic & transparent coating
CA : 149.0±1.6º
Superhydrophilic surface Superhydrophilic surface Antifogging property
Glass slide in a humid air after
cooled in icebox for 20 min. Glass slide holding on a
beaker with 80 hot water ℃
coated uncoated
300 400 500 600 700 80080
85
90
95
100
Tra
nsm
itta
nce (
%)
Wavelength (nm)
glass 110 nm 250 nm 370 nm 1100 nm
T % vs. coating thickness
Superhydrophilic and superhydrophobic surfaceSuperhydrophilic and superhydrophobic surface optical property
Particle diameter vs. T %
14.6nm 18.8nm 7.6nm 7.6nm
Particle diameter vs. CA, roughness
CA 140º CA 138º CA 127º CA 123º
Outline
1.Background
2.Our Work
Transparent superhydrophilic and Ultra-hydrophobic
coatings with anti-fogging & anti-reflective properties
3. Applications in solar cell3. Applications in solar cell
Performance of AR coating on solar cell
4. Conclusion
Solar energy > 25% for total energy in 2050 GDP>100000billion ( RMB )
Based on JRC Report 2004,
Where to for solar cell? Where to for solar cell?
BulkBulkThin-filmThin-film
?
The Third GenerationThe Third GenerationThe Second Generation Generation
The First GenerationGeneration
Size ( mm ): 1580*808*50 Power: 170WProduction Ability: 20,000,000M2/y
An approach enhanced energy efficiency ---Anti-reflection(AR) glass for solar cell
300 400 500 600 700 80080
85
90
95
100tr
an
smitt
an
ce(%
)
Wavelength(nm)
A coated on both sides B uncoated glass
Transmittance: 92 ~ 96.5% in visible spectrum region
The effect of antireflection film on the The effect of antireflection film on the power output of solar cellpower output of solar cell
Incidence angle Incidence angle vs.vs. the power output the power output
Power increase Power increase
3.8-8.5%3.8-8.5%
30o
60o
0o
Durability of the AR coatingDurability of the AR coating
Item Adhesion Pensile hardness Anti steel wool
Adhesion after Boiled in 80˚C water for1 hr
Condition 3M tap 1Kg 350g,10 times
3M tap
Results 100/100 3H ok 100/100 , no fogging
A facile method for fabricating transparent
mulitifunctional film based on nanotechnology
Superhydrophobic or superhydrophilic modification
render the coating antifogging/self-cleaning properties
The antireflection film can increase the power output
of solar cell and can product in industrial-scale
Conclusion
Next projectdevelop AR film on flexible substrate and TFT display
international cooperation
Acknowledgement:
Thank the NSFC and CAS Innovation Project for financial
support.
Many thanks for the colleagues: Taiyue Glass, CEEG
(Shanghai) and Chaori Solar Science & Technology Co., Ltd.
Thanks for your attention !Thanks for your attention !
Special issue for ICCASSpecial issue for ICCAS
2120
201 )(log4
nnn
nnnA
0n
1n
2n
A : Amplitude of the Fabry-Pérot finger peaks
,
: refractive index of air
n1 = p·nair + (1-p) ·nframework
: refractive index of coating
: refractive index of substrate
1n
p : porosity of the coatng nframework : refractive index of the framework
p 21.7%.
1.36
Fabry-Pérot vs. refractive index and porosity
Characterizations of wettability: What is contact angle, hysteresis, sliding angle?
Advancing Angle
Receding Angle
Hysteresis : represent for the hardness of slidding off a solid surface for a liquid drop The sliding angle: the difference between the advancing contact angle (θa) and the receding contact angle (θr))
Definition of contact angle
cos
sv sl
lv
John&Sons, New York 1990.
Oxford University Press, Oxford 1984 Langmuir 1998, 14, 5292-5297
Young's equation
02468
10121416
GW
2005 2006 2007 2008 2009 2010
晶硅 非晶硅薄膜 CdTe CIGS Other
95% 92%
70%
87%
78%
67%
Future for different types of solar cellFuture for different types of solar cell