The Columbia EFRC - Lenfest Center for Sustainable Energy ...
The Columbia EFRC - Lenfest Center for Sustainable Energy ...
The Columbia EFRC - Lenfest Center for Sustainable Energy ...
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<strong>The</strong> <strong>Columbia</strong> <strong>EFRC</strong>: Redefining<br />
Photovoltaic Efficiency Through<br />
Molecule-Scale Control.<br />
James Yardley<br />
Electrical Engineering<br />
Jim Yardley<br />
Louis Brus<br />
Tony Heinz<br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 1
<strong>EFRC</strong> Origins: Basic Research Needs.<br />
file: <strong>EFRC</strong> Program Summary 3-16-10 rev h.ppt Page 2
<strong>Energy</strong> Frontier Research <strong>Center</strong>s: Genesis.<br />
Total Resources: $770 million<br />
over 5 years!<br />
file: <strong>EFRC</strong> Program Summary 3-16-10 rev h.ppt Page 3
<strong>EFRC</strong>: History and Basis<br />
file: <strong>EFRC</strong> Program Summary 3-16-10 rev h.ppt Page 4
<strong>The</strong> <strong>EFRC</strong> Network.<br />
file: <strong>EFRC</strong> Program Summary 3-16-10 rev h.ppt Page 5
Basic Research Needs <strong>for</strong> Solar <strong>Energy</strong>.<br />
• <strong>The</strong> Sun is a singular solution to our future energy needs<br />
- capacity dwarfs fossil, nuclear, wind . . .<br />
- sunlight delivers more energy in one hour<br />
than the earth uses in one year<br />
- free of greenhouse gases and pollutants<br />
- secure from geo-political constraints<br />
• Enormous gap between our tiny use<br />
of solar energy and its immense potential<br />
- Incremental advances in today’s technology<br />
will not bridge the gap<br />
- Conceptual breakthroughs are needed that come<br />
only from high risk-high payoff basic research<br />
• Interdisciplinary research is required<br />
physics, chemistry, biology, materials, nanoscience<br />
• Basic and applied science should couple seamlessly http://www.sc.doe.gov/bes/reports/abstracts.html#SEU<br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 6
Solar Cell Evolution.<br />
Shockley-Queisser Limit<br />
“Organic Photovoltaics”<br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 7
Organic Photovoltaics: Plastic Photocells.<br />
donor-acceptor junction<br />
polymer donor<br />
MDMO-PPV<br />
Opportunities<br />
inexpensive materials, con<strong>for</strong>mal coating, self-assembling fabrication,<br />
wide choice of molecular structures, “cheap solar paint”<br />
Challenges<br />
low efficiency (2-5%), high defect density, low mobility, full<br />
absorption spectrum, nanostructured architecture<br />
Source: George Crabtree, Solar <strong>Energy</strong>Challenges and Opportunities<br />
(<br />
O<br />
O<br />
) n<br />
fullerene acceptor<br />
PCBM<br />
O<br />
OMe<br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 8
<strong>Columbia</strong> <strong>Energy</strong> Frontier Research <strong>Center</strong><br />
<strong>Columbia</strong> University<br />
<strong>Columbia</strong> Nanocenter<br />
Tel Aviv Univ.<br />
Eran Rabani<br />
General Electric<br />
Loucas Tsakalakos<br />
HelioVolt<br />
Louay Eldada<br />
IBM<br />
George Tulevski<br />
State of New York<br />
NYSTAR<br />
NYSERDA<br />
Smart Grid Consortium<br />
Brookhaven National Lab.<br />
<strong>Center</strong> <strong>for</strong> Functional Nanomaterials<br />
Mark Hybertsen<br />
Charles Black<br />
University of Arkansas<br />
Xiaogang Peng<br />
Purdue University<br />
Ashraf Alam<br />
Univ. of Texas<br />
Xiaoyang Zhu<br />
Partners (<strong>EFRC</strong> funded)<br />
Collaborators<br />
Partners (Government)<br />
DOE Funding:<br />
$16 million over 5<br />
years.<br />
Sept. 1, 2009 start.<br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 9
<strong>Columbia</strong> <strong>EFRC</strong>: Research Team.<br />
<strong>Columbia</strong> University Principal Investigators<br />
Simon Billinge, Applied Physics<br />
Louis Brus, Chemistry<br />
George Flynn, Chemistry<br />
Tony Heinz, Electrical Engineering<br />
Irving P. Herman, Applied Physics<br />
James Hone, Mechanical Engineering<br />
Philip Kim, Physics<br />
Ioannis Kymissis, Electrical Engineering<br />
Colin Nuckolls, Chemistry<br />
Richard Osgood, Electrical Engineering<br />
David Reichman, Chemistry<br />
Kenneth Shepard, Electrical Engineering<br />
Mike Steigerwald, Chemistry<br />
Latha Venkataraman, Applied Physics<br />
Chee Wei Wong, Mechanical Engineering<br />
James Yardley, Electrical Engineering<br />
<strong>Columbia</strong> University Seed Fund Faculty<br />
Dirk Englund, Electrical Engineering<br />
Jonathan Owen, Chemistry<br />
Abhay Pasupathy, Physics<br />
Principal Investigators at Partner Institutions<br />
Ashraf Alam, Electrical Engineering, Purdue<br />
Xiaogang Peng, Chemistry, Arkansas Univ.<br />
Xiaoyang Zhu, Chemistry, Univ. Texas, Austin<br />
Ashraf Alam Xiaoyang Zhu Xiaogang Peng<br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 10
<strong>Columbia</strong> <strong>EFRC</strong>: Research Team… Cont.<br />
External Collaborators (Unfunded)<br />
Charles Black, Brookhaven, CFN<br />
Mark S. Hybertsen, Brookhaven, CFN<br />
Eran Rabani, Chemistry, Tel Aviv University<br />
Charles Black<br />
Mark Hybertsen<br />
Eran Rabani<br />
<strong>EFRC</strong> Research Fellows<br />
<strong>The</strong>anne Schiros, <strong>EFRC</strong>, <strong>Columbia</strong> Univ.<br />
Jonathan Schuller, <strong>EFRC</strong>, <strong>Columbia</strong> Univ.<br />
<strong>The</strong>anne Schiros<br />
Jonathan Schuller<br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 11
<strong>The</strong> <strong>Columbia</strong> <strong>EFRC</strong> will create<br />
enabling technology to re-define<br />
efficiency in nanostructured thin-film<br />
organic photovoltaic devices through<br />
fundamental understanding and<br />
through molecule-scale control of<br />
charge <strong>for</strong>mation, separation,<br />
extraction, and transport.<br />
Re-Defining Photovoltaic Efficiency Through<br />
Molecule Scale Control<br />
OVERALL RESEARCH PLAN AND DIRECTIONS<br />
Fundamental understanding of photo-physical and kinetic properties on the<br />
nanoscale will allow us to design systems <strong>for</strong> efficient photovoltaic<br />
generation and separation of charges.<br />
By using new conducting materials such as graphene we can transport these<br />
charges to macroscopic electrical systems, providing basis <strong>for</strong> revolutionary<br />
low cost, high efficiency devices.<br />
an Office of Basic <strong>Energy</strong> Sciences<br />
<strong>Energy</strong> Frontier Research <strong>Center</strong><br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 12
<strong>Columbia</strong> <strong>EFRC</strong> Research Thrusts.<br />
Re-Defining Photovoltaic Efficiency Through Molecule Scale Control.<br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 13
THRUST 1. FUNDAMENTALS OF CHARGE GENERATION: EXCITATION,<br />
SEPARATION, AND EXTRACTION OF CHARGE CARRIERS.<br />
Thrust Leader: Colin Nuckolls<br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 14
New Materials <strong>for</strong> Efficient Charge Extraction<br />
Engineered Quantum Dots<br />
Xiaogang Peng (U Ark)<br />
Simon Billinge<br />
Jonathan Owen<br />
With Chee Wei Wong, Mike Steigerwald, Louis Brus<br />
Molecular Clusters <strong>for</strong> Photovoltaic Cells.<br />
Michael Steigerwald<br />
Jonathan Owen<br />
With Latha Venkataraman<br />
Organic Semiconductors and Nanostructures.<br />
Colin Nuckolls<br />
Ioannis Kymissis<br />
With Jonathan Owen, Mike Steigerwald<br />
Ni 23 Se 12 (PEt 3 ) 13<br />
Program Goal: Develop and engineer new materials that promote<br />
efficient extraction of electron and hole from single exciton.<br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 15
Fundamentals of Charge Transport Across Interfaces.<br />
Transport Across Molecular Junctions.<br />
Latha Venkataraman<br />
Mark Hybertsen (BNL)<br />
Mike Steigerwald<br />
Transport Across Interfaces.<br />
George Flynn<br />
Abhay Pasupathy<br />
Richard Osgood<br />
Xiaoyang Zhu (U Tex.)<br />
Direct map of electron flow.<br />
Program goal: Determine the atomic-scale factors controlling<br />
the efficiency and energetics of charge transfer at materials of<br />
interest <strong>for</strong> nanosolar systems.<br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 16
Optical Nanostructures <strong>for</strong> Efficient Light Collection.<br />
Nanostructured Antennas.<br />
Richard Osgood<br />
Dirk Englund<br />
With Chee Wei Wong<br />
Light Trapping in Thin Films.<br />
Dirk Englund<br />
With Chee Wei Wong<br />
Program goal: Develop integrated optical devices and<br />
structures that optimize coupling of solar radiation with<br />
nanostructured solar devices.<br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 17
THRUST II. CHARGE COLLECTION: TRANSPORT AT<br />
THE NANOSCALE AND BEYOND.<br />
Thrust Leader: Ioannis Kymissis<br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 18
Nanostructured Heterojunction Solar Devices.<br />
Ioannis Kymissis<br />
Charles Black (BNL)<br />
Ashrafel Alam (Purdue)<br />
With Colin Nuckolls, Ken Shepard, Philip Kim, Irving Herman<br />
PDMS molding followed by microcontact<br />
printing of surface modifying silanes<br />
Idea: Engineer surface energy <strong>for</strong> control of<br />
organic blend phase separation.<br />
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� � � �<br />
Program Goal: Develop, understand, and evaluate heterostructure<br />
solar devices with efficient extraction of charge carriers.<br />
p<br />
n<br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 19
Self-Assembled Heterostructure Devices.<br />
Colin Nuckolls<br />
Ioannis Kymissis<br />
With Charles Black (BNL), Colin Nuckolls, Ken Shepard, Philip Kim<br />
Program Goal: Develop and understand heterostructure devices built<br />
upon nanoscale self-assembly.<br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 20
New Concepts <strong>for</strong> Organic Solar Cell Devices.<br />
Photovoltaic Universal Joints: Ball-and-Socket Interfaces in<br />
Molecular Photovoltaic Cells.<br />
Colin Nuckolls<br />
Ioannis Kymissis<br />
Noah Tremblay<br />
Alon Gorodetsky<br />
Marshall Cox<br />
<strong>The</strong>anne Schiros<br />
Michael Steigerwald<br />
(A) Depiction of ball-and-socket interfaces in bilayer and bulk<br />
heterojunction devices.<br />
(B) <strong>The</strong> chemical structure of the contorted-HBC.<br />
(C) Correlation between depiction (top) and molecular structure<br />
from the co-crystal of HBC and C 60 (bottom).<br />
Funded in part by the National Science Foundation under NSF Award Number CHE-0641523, in part from the <strong>Center</strong> <strong>for</strong> Re-Defining Photovoltaic<br />
Efficiency Through Molecule Scale Control, an <strong>Energy</strong> Frontier Research <strong>Center</strong> funded by the U.S. Department of <strong>Energy</strong>, Office of Science,<br />
Office of Basic <strong>Energy</strong> Sciences under Award Number DE-SC0001085, and in part from the Chemical Sciences, Geosciences and Biosciences<br />
Division, Office of Basic <strong>Energy</strong> Sciences, US D.O.E. (#DE-FG02-01ER15264) and US D.O.E. (#DE-FG02-04ER46118).<br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 21
Shape Complementary Molecular Photovoltaics.<br />
electrode 1<br />
n-type semiconductor<br />
p-type semiconductor<br />
electrode 2<br />
p-type n-type<br />
assembly<br />
shapecomplemenarity<br />
Interdigitated columns<br />
HBC/C60 bilayer devices<br />
show good functional<br />
per<strong>for</strong>mance!<br />
Voc=0.95 V, η= 5.7%<br />
(UV), > 1% (amb. solar)<br />
Voc 10x’s larger <strong>for</strong><br />
contorted- vs. flat- HBC<br />
devices (under UV light).<br />
Goal: ordered bulk<br />
heterojunction.<br />
Approach: exploit<br />
physical & electronic<br />
complementarity of C60 with contorted-HBC<br />
(hexabenzocoronene)
Carbon-based Conductor and Semiconductors.<br />
Philip Kim<br />
Tony Heinz<br />
With Ioannis Kymissis, Charles Black (BNL), Ken Shepard.<br />
Conventional solar cells need work<br />
functions matched to materials.<br />
Simplified band diagram (shown at V oc) of a P3HT:PCBM solar cell<br />
having PEDOT and Al contacts.<br />
Band offsets are major source of loss!<br />
Graphene work function is controllable through<br />
chemical doping and through applied electric fields.<br />
Program Goal: Develop carbon-based electrode structures <strong>for</strong> high<br />
efficiency charge extraction from nanostructured heterojunction devices.<br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 23
THRUST 3. CARRIER MULTIPLICATION: BEYOND THE<br />
SHOCKLEY-QUEISSER LIMIT.<br />
Thrust Leader: David Reichman<br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 24
<strong>The</strong>oretical Basis <strong>for</strong> Carrier Multiplication.<br />
David Reichman<br />
Mark Hybertsen (BNL)<br />
Eran Rabani (Tel Aviv)<br />
• Increase PV efficiency<br />
about 40% above S-Q limit.<br />
• Need strong electronelectron<br />
interactions.<br />
Program Goal: Develop broadly-based theoretical model <strong>for</strong><br />
understanding multiple carrier generation in semiconducting materials<br />
including quantum dots, carbon nanotubes, and molecular clusters.<br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 25
MEG in One-Dimensional Systems.<br />
Tony Heinz<br />
Louis Brus<br />
James Hone<br />
Research<br />
Plan<br />
Absorption Spectrum of Individual<br />
(21,21) Armchair Metallic Nanotube<br />
(a) Scanning electron micrograph of an individual SWNT with electrode contacts.<br />
(b) - (d) Fabrication of split gates to produce a controlled p-n junction.<br />
(e) Photocurrent and Rayleigh scattering spectrum.<br />
file: <strong>Lenfest</strong> Symp 05-04-10 rev b.ppt Page 26