Sylvie Morin's Access to Information and Information Overload in Teaching and Research in Chemistry - A Faculty Perspective presentation

1. Access to Information and Information
Overload in Teaching and Research in
Chemistry – A Faculty perspective
Sylvie Morin
Department of Chemistry, York University, Toronto, ON
1

2. Presentation Outline
• Research objectives
• Research highlights
• Access to information and information overload in chemistry
• Information overload and competitiveness
• New funding reality – exploring unknown territories
2

3. Research Objectives
Understand atomic and molecular assemblies at surfaces and develop
ways to control their structure and morphology using chemistry,
interfacial properties and electrochemistry.
Study the performance of these atomic layers and molecular
assemblies in applications such as electrocatalysis, sensors, solar
energy conversion, bio- nano- materials.
Relate a particular property to the layer’s structural, chemical,
electronic and/or electrochemical attributes.
3

4. Solar cell diagram based on sensitization concept
Prof. Grätzel group was the first to build a photo-
voltaic cell using Ru(II) complexes as catalysts more 4
than 20 years ago.

5. Preparation and characterization of TiO2
films
Cross section
SEM Image of
of TiO2 film
Cross section
of TiO2 film
SEM Image of
SEM Image of
TiO22film
TiO film
from Top
(top view) TiO2 layer
Conductive
SnO2 layer
Glass substrate
5

6. Photosensitizer Dye Molecules
Terpyridine
Dipyrazinylpyridine
Dyes
Dyes
RuA2(PF6)2
RuC2(PF6)2
Ru(eA)2(PF6)2
Ru(eC)2(PF6)2
RuB2(PF6)2
RuD2(PF6)2
Ru(eB)2(PF6)2
Ru(eD)2(PF6)2
6
N3

7. Incorporation of nanoparticles in solar cell devices
Why nanoparticles?
By reducing the size of semiconductor
crystals, quantum-size effect alters energy
levels of these crystals.
1. Continuous bands break into discrete
energy levels.
2. Size of the gap increases.
V.I. Klimov, Los Alamos Science (2003) 28, 214-220. 7

8. Sensitization of TiO2 with CdSexS(1-x) ternary alloys semiconductors
Why are we changing the ratios?
a. To vary the band gap and hence the excited state energy of the
sensitizer.
b. We may sensitize TiO2 with different semiconductor
compositions having various absorption spectra, so they may
show different light harvesting efficiencies.
For the deposition of
thin films of the Blue Shift
ternary alloys:
Red Shift
8
R.C. Kainthla et al., J. Electrochem. Soc. (1982) 129, 99-102.

9. Chemical bath deposition effect on the spectral absorption
of CdSexS(1-x) sensitizers
NH3 bath
NTA bath
9

10. Photoelectrochemistry (PEC) of Sensitized Solar Cells
Table 1. PEC of TiO2 films sensitized with different CdSexS(1-x) compositions. The films are sensitized
in a chemical bath based on NTA as complexing agent.
Voc (mV) Jsc (mA/cm2) ff (%) Efficiency (%)
CdS -325 1.32 33.4 0.14
CdSe0.25S0.75 -518 9.06 32.8 1.54
CdSe0.5S0.5 -535 9.97 31.8 1.70
CdSe0.75S0.25 -502 9.47 31.7 1.51
CdSe0.95S0.05 -477 4.98 36.1 0.86
CdSe -453 3.79 44.8 0.77
10

11. Challenges
• Each component of these devices depends on the others
• Each study requires a large amount of chemical and physical
characterization
• Sensitizers – redox couple – additives need to be optimized
each time something is changed in the cell
• Field is evolving fast
11

12. Access to information and information overload in solar cell
research
• Information overload and competitiveness
Observations:
Number of publishing media has increased
Number of research publications has also increased – booming
economies such as China and India have strong research
programs
Funding is limited and often targets narrower fields of research
– e.g. solar energy – fuel cells – CO2 reduction
12

13. Number of research articles published per year obtained from
a simple and limited literature search using the keywords “dye-sensitized”
and “solar” (data source, ISI Web of Knowledge).
13
A. Hagfeldt et al. Chem. Rev. 2010, 110, 6595–6663

14. Reality
• Only the limited number of publications are cited heavily and
they usually originate from very high impact journals.
• Unrealistic to follow all this literature – considering that this
is only one of many areas of investigation in my group
• It becomes very hard to publish in these areas due to large
number of papers being submitted every year – limited
number of specialized journal and referees
• Some specialized journals are not readily available in our
library and there is a lack of skills in data mining
14

15. Access to information and information overload in chemistry
• New funding reality – exploring unknown territories
Observations:
Strong lobbying from industry for Canadian Research to be
more applied – decrease funding in fundamental research – new
programs target partnership with industry
Researchers need to have entrepreneurial skills and take their
ideas to the next level. MITACS programs, NSERC I2I,
NSERC Engage, start-up companies.
Researchers are now required to be comfortable with searching
patent literature and writing confidentiality agreements!
15

16. Number of patent families published per year obtained from
a simple and limited literature search using the keywords “dye-sensitized”
and “solar” (data source, esp@cenet).
16
A. Hagfeldt et al. Chem. Rev. 2010, 110, 6595–6663

17. Access to information and information overload in chemistry
• Impact on teaching and training
Observations:
• New students are inexperienced with basic library searches (UG and G)
• Students rely heavily on web-sites such as Wikipedia and search engines
such as Google (UG)
• Need basic skills to limit number of “hits” using appropriate search
engines otherwise students are overwhelmed (G)
• Basic data mining skills will most likely be required in their future
employment (UG and G)
17

18. Keeping up with large amount of published data is not always a
problem
• Growth and characterization of thin bismuth films
Electrodeposition process is rather simple:
Bi3+(aq) + 3 e- Bio(s)
But the resulting film structure and morphology will depend strongly on
thermodynamic and kinetic effects.
Adapted from: E. Budevski,et al. “Electrochemical
Phase Formation and growth”, VCH, 1996.
18

19. Scanning Tunnelling Microscopy - STM
Conventional STM Video STM
Constant current mode Constant height mode
Fast scan (10~20Hz) is
achieved in solution!
19

20. Scanning Tunneling Microscopy –
bismuth deposition at -80 mV on Au(111)
after 5min at – 80 mV 10min 15min
a) b) c)
150 nm 150 nm 150 nm
20min 25min
d) e) - Early stages: formation of mono-
and bi-layer islands.
- Two growth modes: step-flow
and needle growth.
- Bi layer height: ca. 3.6 ± 0.1 Å.
- Needles have characteristic
90 nm 90 nm orientations where 120º and 60º
Figure 5: In-situ STM images recorded at -80 mV (a-e), Ebias = 60 mV, It = 0.2 angles are predominant.
nA. Arrows = scan direction.
8. Susan H. Zheng, “Studies of Bismuth Electrodeposition on Au(111) by Scanning Tunneling Microscopy and X-ray Diffraction”, MSc Thesis,
York University (2005)

21. Video-STM
STM with high time resolution 
• “fast” dynamic processes
• One group has successfully build
such a STM for studies in solutions
Constant height mode 5 ~ 30 images/s
L. Zitzler, et al., Proc. Electrochem. Soc., 99-28 (2000) 29-38. 21

22. Needle Structure
Needle structure model
Bi atom
Short bond
(46.2 x 46.2Å)
Long bond
Video-STM images (10Hz) of Bi needle
structure deposited in 1 mM Bi3+ at -59 •Stabilized needle step by short bond
mV vs. SCE. •Dynamic fluctuation at needle tip
22

23. Kink Motion
Single kink model
Type A Type B Type C
(41 x 41 Å)
Video-STM images (10Hz) of Bi needle
structure deposited in 1 mM Bi3+ at -229
mV vs. SCE.
23

24. Thank You!
Missing: Dr. Ashur Aushana and Erwin Lin.
NSERC, CRC program and York University
SEM analysis: Karen Rethoret (York)
E-mail: smorin@yorku.ca
24