光催化复合材料

larger specific surface area
more active adsorption sites
J. Phys. Chem. C 2009(113), Wenzhong Wang et al.
Efficient Visible Light-Induced Photocatalytic Degradation of Contaminant by Spindle-like PANI/BiVO4
Intensify the visible light absorption for conducting polymers/TiO2
Use TiO2 with large specific surface area and small crystallite size Increase the optical path length of photons in photocatalyst
P25
PANI/TiO2
are added to
sonicate 30 minrecursor
Dip-coating dry at 10 ◦C for 12 h
films
stir 24 h
Vis(λ>450nm)
UV(λ=254nm)
electrochemical impedance spectroscopy(EIS) Nynquist plots, bias potential is 1.0 V
P25
filter are added to
0.45 g/L PANI+THF
wash
sonicate 30 min stir 24 h
suspension
precipitate
PANI/TiO2
dry at 80 ◦C for 12 h
Visble light: When the ratio got to 3:100, the as-prepared photocatalyst had an optimal photocatalytic activity that could degrade MB by 88% in 5 h and RhB by 97% in 100 min. UV: at the ratio of 3:100, the PANI/ TiO2 samples exhibited the best value of photodegradation of MB by 99.6% in 60 min and RhB 96.5% in 30 min.
Vis(λ>450nm)
UV(λ=254nm)
EDTA (holes scavenger)
t-BuOH (radicals scavenger)
Applied Catalysis B: Environmental 2011 (102), Quan Xie et al.
Remarkable improvement of visible light photocatalysis with PANI modified core–shell mesoporous TiO2 microspheres
PANI
PANI/0.1 wt.% ZnO
PANI/0.25 wt.% ZnO
PANI/0.5 wt.% ZnO
Conclusion
high absorption coefficients in the visible light range(π-π* transition)
efficient carrier-transfer property more valuable in practice for ease of commercial-scale production high stability and does not photocorrode during the photocatalytic oxidation of the pollutant molecules
The radius of the arc on the EIS Nynquist plot reflects the reaction rate occurring at thesurface of electrode.
Oxidative Species and Photocatalytic Mechanisms
PANI modified core–shell mesoporous TiO2 hydrothermal method and chemisorption approach
Characterization: SEM&TEM, XRD, FTIR, Nitrogen adsorption, DRS Photocatalytic activity: 25mg Cat., visible light ( λ> 400 nm) RhB (50 mL, 10mg/L) or 4-CP (50 mL, 10mg/L)
Ref. system Preparation Illumination wavelength visible light ( λ> 400 nm) Evaluation of PC activity 10 mg/L RhB 10 mg/L 4-CP
[1] [2] [3] [4]
PANI/TiO2 PANI/TiO2–Fe3+ PANI/CdS PANI/BiVO4
light harvest efficiency
core–shell mesoporous structure
separation efficiency of photogenerated charges
the heterojunction between TiO2 and PANI
the interfacial reaction process
PANI 复合光催化剂研究进展
2011-3-12
Background
Metal ion & non-metal doping chemisorption noble metal deposition in situ polymerization narrow band-gap semiconductors coupling dye sensitization conducting polymers: polyaniline, polythiophene, Polypyrrol
chemisorption in situ polymerization chemisorption chemisorption
UV light (λ = 253.7 nm) 20 mg.L-1 MO & Sunlight visible light (λ > 450 nm) visible light (λ > 420 nm) Visible light 20 mg.L-1 MB 10 mg/L RhB 1 × 10-5 ~1 × 10-4 M phenol 10 mg.L-1 MB
Spindle-like 0.5% PANI/BiVO4 sample
Photocatalytic degradation of phenol with 0.5% PANI/BiVO4 under visible-light by different amounts of H2O2
λ>420nm
Colloid Polym Sci 2011(289), Hyung-Shik Shin et al. An effective nanocomposite of polyaniline and ZnO: preparation, characterizations, and its photocatalytic activity in situ polymerization of aniline monomer with ZnO nanomaterials
[5]
PANI/ZnO
in situ polymerization
Environ. Sci. Technol. 2008(42), Yongfa Zhu et al.
Dramatic Visible Photocatalytic Degradation Performances Due to Synergetic Effect of TiO2 with PANI
It is expected that the combination of photocatalyst and PANI seems to be ideal for enhancing the photoactivity under visible light. 工作计划：利用化学吸附法制备PANI/TiO2-NTs复合光催化剂
RhB
4-CP
Discussion on photocatalytic mechanism of PANI/M-TiO2 photocatalytic activity was mainly governed by three properties:
more PANI because of the large specific surface area facilitate the propagation of light and increase the optical path length in photocatalyst