Exciton dissociation in solar cells:
|
|
- Marcia Evans
- 8 years ago
- Views:
Transcription
1 Exciton dissociation in solar cells: Xiaoyang Zhu Department of Chemistry University of Minnesota, Minneapolis t (fs) 3h! E, k h! Pc Bi e - 1
2 Acknowledgement Organic semiconductors: Mutthias Muntwiler, Qingxin Yang Inorganic quantum dots: William Tisdale, Kenrick Williams Prof. Eray Aydil, Prof. David Norris Funding: NSF (DMR, MRSEC, NIRT) DOE (Solar Initiative) MN-IREE (Initiative for Renewable Energy & Environment) 2
3 Outline Introduction - Excitons & photovoltaics Charge transfer (CT) excitons on organic semiconductor surfaces: Direct time domain observation of 2D polarons Extracting hot or multiple carriers from inorganic quantum dots: 3
4 The conventional solar cell: p-n junction Fermi p e n Conduction band h Valence band Light absorption & charge separation occur in same location Charge separation by build-in electric field UMN solar car 4
5 Excitonic solar cells electrolyte I - /I 3 - transparent anode cathode M Gratzel, Nature (21), Leschkies et al., Nano Lett (27) e A D Tang, APL (1986) Acceptor h Donor 5
6 The Coulomb barrier problem Exciton: an electron-hole pair Molecular or Frenkel exciton in an organic semiconductor or inorganic quantum dot Charge transfer exciton at a D/A interface D A V = e 2-4!""o r Large binding energy (>> kt) due to the low dielectric constant! 6
7 What drives exciton dissociation? BE ex How does a Frenkel exciton dissociate? BE CT # LUMO > BE ex How does a CT exciton separate? #µ, but Frenkel or 7
8 Probing electron dynamics in the time domain: femtosecond two-photon photoemission! e -.2 Binding Energy (ev) n = 1 image state, 2 ML nonane/cu(111) Pump-Probe Delay (fs) 4 Lindstrom, Zhu Chem. Rev. (6) 8
9 How do charge carriers separate in an organic heterojunction solar cell? A D 9
10 Previous suggestion of long distance geminate e-h pair in exciton dissociation Morteani et al. PRL 92, (24) Adv. Mater. 15, 178 (23) 1
11 Previous evidence for the need of excess energetic driving force in exciton dissociation Coulombically bound radical pair (BRP) Nanocrystalline polythiophene/pcbm Amorphous polythiophene/pcbm Ohkita et al. JACS 13, 33 (28) 11
12 Charge transfer exciton: a toy model..2 1s 1p 2s 2s 1d D + r o r A E B (ev).4.6 1p e 1s.8 1.eV x (Å) z (Å) 12
13 Experimental realization of the toy model for CT excitons " Pc = 5.3," o = 1. # " =
14 Image potential state as the electron acceptor (Geminate pair) What is the binding energy of a CT exciton (geminate pair)? How to overcome this binding energy in charge separation? 14
15 The model system: crystalline pentacene thin films grown on Bi Sadowski et al, Appl Phys Lett 25 Thayer et al, Phys Rev Lett 25 15
16 2PPE spectra: IPS & CT exciton 3 1h! Pc coverage (ML) CT 1s h! 2 = 1.39 ev h! 1 = 4.16 ev Bi 2 1 IPS ev 1..5 E B (ev) ev -1.2 (Bi) 16
17 Spatial distribution of IPS & CT exciton " Nonane overlayer quenches both IPS and the CT exciton state IPS shows dispersion & CT exciton state is localized. m eff = 1.5 m e 13 fs 7 fs " 2 is on the surface 17
18 Origin of charge transfer excitons E r r o x z E (atomic units)!! = " # 1 " + 1 [jackson, classical electrodynamics] $ = 2 " + 1 y x 18
19 Simulation results: the delocalized image band 2p 2s 1p 1s?= 519
20 Simulation results: the localized CT excitons angular momentum l z 1s 1 Å 1p 1d 1f E = ev s 2p 2d 2f nodes s 3p 3d 3f
21 Simulation: CT exciton binding energies a. ECTE (ev).4 c.2 E,1s (ev) s 2p 3s 1d 2s 1p 2 4 x (Å) 6 6 _ 5 b energy scale E CTE 2 _ _ internal Coulomb 1s energy of 1 the exciton = bottom of IPS band (continuum)! 1s 1?= -1 1s.45 ev 1p.265 ev 1 2s.197 1p ev 1d.156 ev 2p.132 ev -1 3s.17 ev z (Å) y (Å) y (Å) (Å) 1 2s 21
22 Seeing hot excitons at higher h! a c ECTE (ev) ECTE,1s (ev) UV pump from HOMO.4 _ s 3s 2p 1d 2s 1p 2 4 x (Å) b z (Å) kcounts/s y (Å) 2 _ _ y (Å) y (Å) s 1s 1p 2s 2.8 1s UV only or long pump-probe delay 3. ev HOMO 1p forbidden 3.2 2s 3s 1 ML pentacene Pump: 4.38 ev Probe: 1.46 ev 3.4 IPS
23 CT excitons - the complete picture 3.6 IPS 6x1 5 CT 1s E - E Fermi (ev) s+ 2s 1s 2 4 Pump-probe delay (fs) Photoelectron intensity (c/s) CT 2s CT 3s +... IPS! t = fs 16 fs 1 ML pentacene fs Pump: 4.38 ev; Probe: 1.46 ev E - E Fermi (ev) 23
24 All CT excitons show no dispersion: photo-ionization destroys the quasi-particle! IPS E kin = ( hk)2 2m E - E Fermi (ev) ML pentacene s 1d? 2s 1s m= 1.5 m e Dispersion measurement carried out at h! 1 = 4.38 ev & h! 2 = 1.46 ev; time delay = 8 fs Detection angle 24
25 CT excitons on thick pentacene films >2 nm pentacene/si(111) 6x CT 1s E-E F (ev) Pump-probe delay (fs) x1 5 Photoelectron intensity (c/s) ! t / fs E - E Fermi (ev) CT 2s CT 3s +... IPS Pump: 4.59 ev; Probe: 1.53 ev 25
26 Why do CT excitons on pentacene decay so fast? ML > 1 ML 11 fs fs E-E F (ev) fs E-E F (ev) fs fs Pump-probe delay (fs) Pump-probe delay (fs) Short lifetimes: resonance with LUMO+x bands 26
27 Surface CT excitons are general: tetracene 4.2!2 nm tetracene/si(111)!tuning h! to reach each resonance IPS (standing up) E-E F (ev) h! 1 =4.28 ev CT 1s IPS (lying down) Time delay (fs) IPS (n=1) E-E F (ev) h! 1 =4.77 ev E-E F (ev) h! 1 =4.59 ev 3.4 CT 1s 3.4 CT 1s Time delay (fs) Time delay (fs) 27
28 The difference between surface CT excitons and the toy D/A model. CT exciton at D/A interface. CT exciton at surface.2 1s 1p 2s 1d.2 E B (ev).4.6 2s E B (ev).4.6 1d 2s 2s IPS band bottom 1p.8.8 1s 1.eV 2 4 z (Å) eV 2 4 z (Å) 6 8 1A 28
29 The hot mechanism for charge carrier separation in organic photovoltaic Conclusion: Charge separation at a D/A interface in OPV must involve hot CT excitons! n > 1 Less CT binding energy Longer lifetime More delocalization Better electronic coupling (energy denominator!) 29
30 Other interesting systems Donor Acceptor Donor Acceptor 3
31 Summary 1 Charge transfer excitons are seen on the crystalline pentacene and tetracene surfaces. Hot CT excitons are necessary in organic heterojunction photovoltaic. 31
32 Challenge to theory/simulation: breaking up the quasiparticle D k A A + $ e k = k A - k D k D "( k, $ ) What is the role of delocalization on interfacial charge separation? 32
33 Polarons & localization Electronic-nuclear coupling Defects Appl. Phys. Lett. 5 Energetics of self-trapping: E LUMO band "E ST = E pol + E loc + E bond BW! Polarization gain (negative) Localization penalty (positive) ".5# BW "p# "x $ h k 33
34 Self trapping not observed. Tetracene/Silicon(111), 15 K, thick film (> 2 nm) 4.2 n = s ev n = s Energy relaxation negligible: No lattice polaron formation. 34
35 2D polarons that are absent in 3D Cl - Na + e Na + Cl - Cl - e Na+ Na + Cl - Not an organic, but same physics Model: NaCl/Cu(111) 35
36 Polaron formation in time-energy domain NaCl conduction band (CB) # trap = 62 ± 8 fs, # decay = 12 ± 2 fs Interface $E = 6±1 mev polaron NaCl interface band (IB) # trap = 135 ± 47 fs, # decay = 23 image ± 2 fs $E = -85 ± 1 mev polaron Pump-probe delay (fs) 3ML NaCl/Cu(111) Muntwiler & Zhu, Phys. Rev. Lett
37 Where is the % 2? Effect of an overlayer bulk polaron NaCl/Cu Interface polaron image polaron 3ML NaCl/Cu(111) 1 ML nonane/3ml NaCl/Cu(111) 37
38 Polaron formation in the momentum domain Parallel dispersions 3 ML NaCl/Cu(111) Conduction band Interface band 38
39 Why does an electron polaron form in a 2D NaCl film but not in 3D NaCl? Cl - Na + e Na + Cl - Cl - Na Na + Cl - Conduction band width = 5. ev "E ST = E pol + E loc + E bond Bulk crystal -.5 ev 2.5 ev -1. ev "E ST #1. ev! Thin film (1 unit cell thick) -1. ev 1.7 ev -1. ev More deformable and narrower bandwidth in a thin film. Delocalization localization!! Does it apply to thin films in general? Quantum wells?! "E ST # $.3eV 39
40 Conclusion 2 TR-2PPE of NaCl/Cu(111) provides time-domain evidence of a 2D polaron. Polarons or self-trapped excitons must be important to exciton dissociation at organic D/A interfaces (not directly observed in the time domain yet..) 4
41 Challenge to theory/simulation: delocalization + localization D k A A + $ e k = k A - k D k D "( k, $ ) Now add localization from electronnuclear coupling & trapping! My head is spinning 41
Exciton Fission & Solar energy conversion beyond the limit. Xiaoyang Zhu, Columbia University 1
Exciton Fission & Solar energy conversion beyond the limit 1 Acknowledgement Dr. Wai-lun Chan (U. Kansas) Dr. John Tritsch (Intel) Dr. M. Tuan Trinh Mr. Tim Berkelbach, Dr. Mark Hybertsen, Prof. David
More informationOrganic semiconductors
Plastic (Organic) Solar Cells: Accomplishments, Challenges, and Strategies Sumit Chaudhary Assistant Professor Department of Electrical and Computer Engineering Materials Science and Engineering Iowa State
More informationIntroduction OLEDs OTFTs OPVC Summary. Organic Electronics. Felix Buth. Walter Schottky Institut, TU München. Joint Advanced Student School 2008
Felix Buth Joint Advanced Student School 2008 Outline 1 Introduction Difference organic/inorganic semiconductors From molecular orbitals to the molecular crystal 2 Organic Light Emitting Diodes Basic Principals
More informationBroadband THz Generation from Photoconductive Antenna
Progress In Electromagnetics Research Symposium 2005, Hangzhou, China, August 22-26 331 Broadband THz Generation from Photoconductive Antenna Qing Chang 1, Dongxiao Yang 1,2, and Liang Wang 1 1 Zhejiang
More informationMagneto-Optical Studies on Internal Photovoltaic Processes in Organic Solar Cells
Magneto-Optical tudies on Internal Photovoltaic Processes in Organic olar Cells Bin Hu Department of Materials cience and Engineering University of Tennessee, Knoxville Wu Han National Laboratory for Optoelectronics
More informationHard Condensed Matter WZI
Hard Condensed Matter WZI Tom Gregorkiewicz University of Amsterdam VU-LaserLab Dec 10, 2015 Hard Condensed Matter Cluster Quantum Matter Optoelectronic Materials Quantum Matter Amsterdam Mark Golden Anne
More informationThe Application of Density Functional Theory in Materials Science
The Application of Density Functional Theory in Materials Science Slide 1 Outline Atomistic Modelling Group at MUL Density Functional Theory Numerical Details HPC Cluster at the MU Leoben Applications
More informationHigh Open Circuit Voltage of MQW Amorphous Silicon Photovoltaic Structures
High Open Circuit Voltage of MQW Amorphous Silicon Photovoltaic Structures ARGYRIOS C. VARONIDES Physics and EE Department University of Scranton 800 Linden Street, Scranton PA, 18510 United States Abstract:
More informationApplied Physics of solar energy conversion
Applied Physics of solar energy conversion Conventional solar cells, and how lazy thinking can slow you down Some new ideas *************************************************************** Our work on semiconductor
More informationLecture 15 - application of solid state materials solar cells and photovoltaics. Copying Nature... Anoxygenic photosynthesis in purple bacteria
Lecture 15 - application of solid state materials solar cells and photovoltaics. Copying Nature... Anoxygenic photosynthesis in purple bacteria Simple example, but still complicated... Photosynthesis is
More informationSolid State Detectors = Semi-Conductor based Detectors
Solid State Detectors = Semi-Conductor based Detectors Materials and their properties Energy bands and electronic structure Charge transport and conductivity Boundaries: the p-n junction Charge collection
More informationLecture 3: Optical Properties of Bulk and Nano. 5 nm
Lecture 3: Optical Properties of Bulk and Nano 5 nm First H/W#1 is due Sept. 10 Course Info The Previous Lecture Origin frequency dependence of χ in real materials Lorentz model (harmonic oscillator model)
More informationLecture 3: Optical Properties of Bulk and Nano. 5 nm
Lecture 3: Optical Properties of Bulk and Nano 5 nm The Previous Lecture Origin frequency dependence of χ in real materials Lorentz model (harmonic oscillator model) 0 e - n( ) n' n '' n ' = 1 + Nucleus
More informationPOLYMER BASED PHOTOVOLTAICS
PLYMER BASED PHTVLTAICS Novel concepts, materials and state-of-the-art performances Jan Kroon Semiconducting polymers Nobel Prize Chemistry 2000 (Alan J. Heeger, Alan G. MacDiarmid, Hideki Shirakawa) Conducting
More informationThe Physics of Energy sources Renewable sources of energy. Solar Energy
The Physics of Energy sources Renewable sources of energy Solar Energy B. Maffei Bruno.maffei@manchester.ac.uk Renewable sources 1 Solar power! There are basically two ways of using directly the radiative
More informationCurriculum Vitae. William A. Tisdale
Curriculum Vitae William A. Tisdale Department of Chemical Engineering voice: (617) 253-4975 Massachusetts Institute of Technology fax: (617) 258-5766 Room 66-458 email: tisdale@mit.edu 77 Massachusetts
More informationPhotoinduced volume change in chalcogenide glasses
Photoinduced volume change in chalcogenide glasses (Ph.D. thesis points) Rozália Lukács Budapest University of Technology and Economics Department of Theoretical Physics Supervisor: Dr. Sándor Kugler 2010
More informationCharacteristic curves of a solar cell
Related Topics Semi-conductor, p-n junction, energy-band diagram, Fermi characteristic energy level, diffusion potential, internal resistance, efficiency, photo-conductive effect, acceptors, donors, valence
More information1938-17. Workshop on Nanoscience for Solar Energy Conversion. 27-29 October 2008
1938-17 Workshop on Nanoscience for Solar Energy Conversion 27-29 October 2008 Mesoscopic Donor-Acceptor Multilayer by Ultra-High-Vacuum Deposition of Zn-Tetraphenyl-Porphyrin and C70 Andrea GOLDONI Area
More informationCrystalline solids. A solid crystal consists of different atoms arranged in a periodic structure.
Crystalline solids A solid crystal consists of different atoms arranged in a periodic structure. Crystals can be formed via various bonding mechanisms: Ionic bonding Covalent bonding Metallic bonding Van
More informationSize effects. Lecture 6 OUTLINE
Size effects 1 MTX9100 Nanomaterials Lecture 6 OUTLINE -Why does size influence the material s properties? -How does size influence the material s performance? -Why are properties of nanoscale objects
More informationArizona Institute for Renewable Energy & the Solar Power Laboratories
Arizona Institute for Renewable Energy & the Solar Power Laboratories International Photovoltaic Reliability Workshop July 29-31, Tempe AZ Christiana Honsberg, Stephen Goodnick, Stuart Bowden Arizona State
More informationSinglet fission for solar energy conversion A theoretical insight. David Casanova
Singlet fission for solar energy conversion A theoretical insight David Casanova Quantum Days in Bilbao July 16, 2014 Harvesting Solar Energy Solar energy 1h = 1 year human consumption We use ~ 0.07% Earth
More informationIntroduction to OLED technology 1. General characteristics
www.osram-oled.com Introduction to OLED technology 1. General characteristics 1.1. Structure An organic light-emitting diode (OLED) consists of several semiconducting organic layers sandwiched between
More informationIntroduction to Quantum Dot Nanocrystals and Nanocrystal Solids. Nuri Yazdani, 10.03.15
Introduction to Quantum Dot Nanocrystals and Nanocrystal Solids Nuri Yazdani, 10.03.15 What is a QD Nanocrystal Time: ~15m What is a QD nanocrystal? Bulk Crystal Periodic lattice of atoms which extends
More informationSpectral Characterisation of Photovoltaic Devices Technical Note
Spectral Characterisation of Photovoltaic Devices Technical Note Introduction to PV This technical note provides an overview of the photovoltaic (PV) devices of today, and the spectral characterisation
More informationEnhanced Charge Separation in Organic Photovoltaic Films Doped with Ferroelectric Dipoles. Supporting Information
Enhanced Charge Separation in Organic Photovoltaic Films Doped with Ferroelectric Dipoles Kanwar S. Nalwa, a John A. Carr, a Rakesh C. Mahadevapuram, b Hari K. Kodali, c Sayantan Bose, d Yuqing Chen, a
More informationChemical Synthesis. Overview. Chemical Synthesis of Nanocrystals. Self-Assembly of Nanocrystals. Example: Cu 146 Se 73 (PPh 3 ) 30
Chemical Synthesis Spontaneous organization of molecules into stable, structurally well-defined aggregates at the nanometer length scale. Overview The 1-100 nm nanoscale length is in between traditional
More informationMagnetization dynamics in lanthanides new frontiers in spin-dependent band mapping at BESSY VSR
1 FEMTOMAGNETISM BESSY VSR 1 Magnetization dynamics in lanthanides new frontiers in spin-dependent band mapping at BESSY VSR Martin Weinelt 2 FEMTOMAGNETISM BESSY VSR 2 Photon flux Ti:Sa UV 10 mw 86 MHz,
More informationNANO SILICON DOTS EMBEDDED SIO 2 /SIO 2 MULTILAYERS FOR PV HIGH EFFICIENCY APPLICATION
NANO SILICON DOTS EMBEDDED SIO 2 /SIO 2 MULTILAYERS FOR PV HIGH EFFICIENCY APPLICATION Olivier Palais, Damien Barakel, David Maestre, Fabrice Gourbilleau and Marcel Pasquinelli 1 Outline Photovoltaic today
More informationA metal-free polymeric photocatalyst for hydrogen production from water under visible light
A metal-free polymeric photocatalyst for hydrogen production from water under visible light Xinchen Wang, Kazuhiko Maeda, Arne Thomas, Kazuhiro Takanabe, Gang Xin, Johan M. Carlsson, Kazunari Domen, Markus
More informationAn organic semiconductor is an organic compound that possesses similar
MSE 542 Final Term Paper Title: Organic Semiconductor for Flexible Electronics Name: Chunhung Huang Introduction: An organic semiconductor is an organic compound that possesses similar properties to inorganic
More information- particle with kinetic energy E strikes a barrier with height U 0 > E and width L. - classically the particle cannot overcome the barrier
Tunnel Effect: - particle with kinetic energy E strikes a barrier with height U 0 > E and width L - classically the particle cannot overcome the barrier - quantum mechanically the particle can penetrated
More informationUltrahigh-efficiency solar cells based on nanophotonic design
Ultrahigh-efficiency solar cells based on nanophotonic design Albert Polman Piero Spinelli Jorik van de Groep Claire van Lare Bonna Newman Erik Garnett Marc Verschuuren Ruud Schropp Wim Sinke Center for
More informationSUPERCONDUCTIVITY. PH 318- Introduction to superconductors 1
SUPERCONDUCTIVITY property of complete disappearance of electrical resistance in solids when they are cooled below a characteristic temperature. This temperature is called transition temperature or critical
More informationPhotovoltaic and Photoelectrochemical Solar Cells
Photovoltaic and Photoelectrochemical Solar Cells EDDIE FOROUZAN, PH.D. ARTIN ENGINEERING AND CONSULTING GROUP, INC. 7933 SILVERTON AVE. #715 SAN DIEGO, CA 92128 PSES San Diego Chapter 2012-02-10 History
More informationPHYSICAL METHODS, INSTRUMENTS AND MEASUREMENTS Vol. IV Femtosecond Measurements Combined With Near-Field Optical Microscopy - Artyom A.
FEMTOSECOND MEASUREMENTS COMBINED WITH NEAR FIELD OPTICAL MICROSCOPY Artyom A. Astafiev, Semyonov Institute of Chemical Physics, Moscow, Russian Federation. Keywords: diffraction limit nearfield scanning
More informationLecture 6 Scanning Tunneling Microscopy (STM) General components of STM; Tunneling current; Feedback system; Tip --- the probe.
Lecture 6 Scanning Tunneling Microscopy (STM) General components of STM; Tunneling current; Feedback system; Tip --- the probe. Brief Overview of STM Inventors of STM The Nobel Prize in Physics 1986 Nobel
More informationMolecular Dynamics Simulations
Molecular Dynamics Simulations Yaoquan Tu Division of Theoretical Chemistry and Biology, Royal Institute of Technology (KTH) 2011-06 1 Outline I. Introduction II. Molecular Mechanics Force Field III. Molecular
More informationTimothy M. Burke, Sean Sweetnam, Koen Vandewal, and Michael D. McGehee* FULL PAPER. 1. Introduction. 2. Background Information
www.materialsviews.com Beyond Langevin Recombination: How Equilibrium Between Free Carriers and Charge Transfer States Determines the Open-Circuit Voltage of Organic Solar Cells Timothy M. Burke, Sean
More information3. Diodes and Diode Circuits. 3. Diodes and Diode Circuits TLT-8016 Basic Analog Circuits 2005/2006 1
3. Diodes and Diode Circuits 3. Diodes and Diode Circuits TLT-8016 Basic Analog Circuits 2005/2006 1 3.1 Diode Characteristics Small-Signal Diodes Diode: a semiconductor device, which conduct the current
More informationChapter 5. Second Edition ( 2001 McGraw-Hill) 5.6 Doped GaAs. Solution
Chapter 5 5.6 Doped GaAs Consider the GaAs crystal at 300 K. a. Calculate the intrinsic conductivity and resistivity. Second Edition ( 2001 McGraw-Hill) b. In a sample containing only 10 15 cm -3 ionized
More informationChapter 8. Exciton solar cells ORGANIC SOLAR CELLS
Chapter 8. ORGAIC SOLAR CELLS Tom J. Savenije DelftChemTech, Faculty of Applied Sciences Delft University of Technology Prof. Dr. Rene Janssen from the Departments of Chemical Engineering & Chemistry and
More informationMBA Lattice Upgrade: New Opportunities for In-situ High Energy (30 kev 90 kev) X-ray Structural Analyses
MBA Lattice Upgrade: New Opportunities for In-situ High Energy (30 kev 90 kev) X-ray Structural Analyses David Tiede Chemical Sciences and Engineering Division Argonne National Laboratory Workshop on New
More informationFrom Nano-Electronics and Photonics to Renewable Energy
From Nano-Electronics and Photonics to Renewable Energy Tom Smy Department of Electronics, Carleton University Questions are welcome! OUTLINE Introduction: to EE and Engineering Physics Renewable Energy
More informationModeling Dye Sensitized Solar Cells Filippo De Angelis
Modeling Dye Sensitized Solar Cells Filippo De Angelis Computational Laboratory for Hybrid/Organic Photovoltaics (CLHYO) Istituto CNR di Scienze e Tecnologie Molecolari (ISTM), I-06123 Perugia, Italy Computational
More informationEffect of 2D delocalization on charge. R. Österbacka
Effect of 2D delocalization on charge transport and recombination in bulkheterojunction solar cells R. Österbacka The people! Drs: H. Majumdar, S. Majumdar, T. Mäkelä, T. Remonen ÅA PhD students: H. Aarnio,
More informationCharge Generation, Transport and Recombination in Organic Solar Cells. Ralf Mauer
Charge Generation, Transport and Recombination in Organic Solar Cells Ralf Mauer Dissertation zur Erlangung des Grades eines Doktor rerum naturalium (Dr. rer. nat.) der Fachbereiche: 08 - Physik, Mathematik
More informationMaterials for Organic Electronic. Jeremy Burroughes FRS FREng
Materials for Organic Electronic Applications Jeremy Burroughes FRS FREng Introduction Organic Thin Film Transistors Organic Solar Cells and Photodiodes All Printed OLED Summary 4k2k 56 Displays Panasonic
More informationHigh Efficiency Black Polymer Solar Cells November 2012 Annual Report
High Efficiency Black Polymer Solar Cells November 2012 Annual Report PI: Dr. Franky So External Collaborators: John Reynolds, Georgia Tech Industry Partner: Sestar Technologies, LLC Students: Cephas Small
More informationGraphene a material for the future
Graphene a material for the future by Olav Thorsen What is graphene? What is graphene? Simply put, it is a thin layer of pure carbon What is graphene? Simply put, it is a thin layer of pure carbon It has
More informationEE 332 Photovoltaic Cell Design Iowa State University Electrical and Computer Engineering Dept
EE 332 Photovoltaic Cell Design Iowa State University Electrical and Computer Engineering Dept Authors: Bai Rui, Senior Electrical Engineering Cui Qiaoya, Senior Electrical Engineering Chris Krantz, Senior
More informationFUNDAMENTAL PROPERTIES OF SOLAR CELLS
FUNDAMENTAL PROPERTIES OF SOLAR CELLS January 31, 2012 The University of Toledo, Department of Physics and Astronomy SSARE, PVIC Principles and Varieties of Solar Energy (PHYS 4400) and Fundamentals of
More informationCharge generation in polymer-fullerene bulkheterojunction
Charge generation in polymer-fullerene bulkheterojunction solar cells Feng Gao and Olle Inganäs Linköping University Post Print N.B.: When citing this work, cite the original article. Original Publication:
More informationScanning Near Field Optical Microscopy: Principle, Instrumentation and Applications
Scanning Near Field Optical Microscopy: Principle, Instrumentation and Applications Saulius Marcinkevičius Optics, ICT, KTH 1 Outline Optical near field. Principle of scanning near field optical microscope
More informationOptical Hyperdoping: Transforming Semiconductor Band Structure for Solar Energy Harvesting
Optical Hyperdoping: Transforming Semiconductor Band Structure for Solar Energy Harvesting 3G Solar Technologies Multidisciplinary Workshop MRS Spring Meeting San Francisco, CA, 5 April 2010 Michael P.
More informationFree Electron Fermi Gas (Kittel Ch. 6)
Free Electron Fermi Gas (Kittel Ch. 6) Role of Electrons in Solids Electrons are responsible for binding of crystals -- they are the glue that hold the nuclei together Types of binding (see next slide)
More informationPCV Project: Excitons in Molecular Spectroscopy
PCV Project: Excitons in Molecular Spectroscopy Introduction The concept of excitons was first introduced by Frenkel (1) in 1931 as a general excitation delocalization mechanism to account for the ability
More informationNew magnetism of 3d monolayers grown with oxygen surfactant: Experiment vs. ab initio calculations
New magnetism of 3d monolayers grown with oxygen surfactant: Experiment vs. ab initio calculations 1. Growth and structure 2. Magnetism and MAE 3. Induced magnetism at oxygen Klaus Baberschke Institut
More informationSOLAR ELECTRICITY: PROBLEM, CONSTRAINTS AND SOLUTIONS
SOLAR ELECTRICITY: PROBLEM, CONSTRAINTS AND SOLUTIONS The United States generates over 4,110 TWh of electricity each year, costing $400 billion and emitting 2.5 billion metric tons of carbon dioxide (Yildiz,
More informationProduction of Solar Energy Using Nanosemiconductors
Production of Solar Energy Using Nanosemiconductors 1 Kiruthika S, 2 Dinesh Kumar M, 3 Surendar.A 1, 2 II year, KSR College of Engineering, Tiruchengode, Tamilnadu, India 3 Assistant Professor, KSR College
More informationFirst Principles Computational Modelling of Solid/Liquid Interfaces for Solar Energy and Solar Fuels
First Principles Computational Modelling of Solid/Liquid Interfaces for Solar Energy and Solar Fuels Mariachiara Pastore Computational Laboratory for Hybrid/Organic Photovoltaics (CLHYO) Istituto CNR di
More informationSEMICONDUCTOR I: Doping, semiconductor statistics (REF: Sze, McKelvey, and Kittel)
SEMICONDUCTOR I: Doping, semiconductor statistics (REF: Sze, McKelvey, and Kittel) Introduction Based on known band structures of Si, Ge, and GaAs, we will begin to focus on specific properties of semiconductors,
More informationEnergy band diagrams. Single atom. Crystal. Excited electrons cannot move. Excited electrons can move (free electrons)
Energy band diagrams In the atoms, the larger the radius, the higher the electron potential energy Hence, electron position can be described either by radius or by its potential energy In the semiconductor
More informationSemiconductor doping. Si solar Cell
Semiconductor doping Si solar Cell Two Levels of Masks - photoresist, alignment Etch and oxidation to isolate thermal oxide, deposited oxide, wet etching, dry etching, isolation schemes Doping - diffusion/ion
More informationBasic principles and mechanisms of NSOM; Different scanning modes and systems of NSOM; General applications and advantages of NSOM.
Lecture 16: Near-field Scanning Optical Microscopy (NSOM) Background of NSOM; Basic principles and mechanisms of NSOM; Basic components of a NSOM; Different scanning modes and systems of NSOM; General
More informationNanoparticles, nanocrystals, and quantum dots What they are, why they re interesting, and what we can do with them
Nanoparticles, nanocrystals, and quantum dots What they are, why they re interesting, and what we can do with them J. Nadeau, Department of Biomedical Engineering jay.nadeau@mcgill.ca Colloidal nanocrystals
More informationTobias Märkl. November 16, 2009
,, Tobias Märkl to 1/f November 16, 2009 1 / 33 Content 1 duction to of Statistical Comparison to Other Types of Noise of of 2 Random duction to Random General of, to 1/f 3 4 2 / 33 , to 1/f 3 / 33 What
More informationThe study of deep-level emission center in ZnO films grown on c-al 2 O 3 substrates
The study of deep-level emission center in ZnO films grown on c-al 2 O 3 substrates Guotong Du Yuantao Zhang, Jinzhong Wang, Yongguo Cui (College of Electronic Science and Engineering, State Key Laboratory
More informationUltrafast Interfacial Proton-Coupled Electron Transfer
1 2/3/06 Ultrafast Interfacial Proton-Coupled Electron Transfer Bin Li 1, Jin Zhao 1, Ken Onda 1, Kenneth D. Jordan 2, Jinlong Yang 3, and Hrvoje Petek 1* 1 Department of Physics and Astronomy, University
More informationApplications of Quantum Chemistry HΨ = EΨ
Applications of Quantum Chemistry HΨ = EΨ Areas of Application Explaining observed phenomena (e.g., spectroscopy) Simulation and modeling: make predictions New techniques/devices use special quantum properties
More informationPhysical Properties and Functionalization of Low-Dimensional Materials
Physical Properties and Functionalization of Low-Dimensional Materials Physics Department, University of Trieste Graduate School of Physics, XXVI cycle Supervisor: Co-supervisor: Prof. Alessandro BARALDI
More informationSpin-polarized scanning tunneling microscopy studies on in-plane magnetization components of thin antiferromagnetic films on Fe(001) Dissertation
Spin-polarized scanning tunneling microscopy studies on in-plane magnetization components of thin antiferromagnetic films on Fe(001) Dissertation zur Erlangung des akademischen Grades doctor rerum naturalium
More informationChapter 8 Concepts of Chemical Bonding
Chapter 8 Concepts of Chemical Bonding Chemical Bonds Three types: Ionic Electrostatic attraction between ions Covalent Sharing of electrons Metallic Metal atoms bonded to several other atoms Ionic Bonding
More informationExplain the ionic bonds, covalent bonds and metallic bonds and give one example for each type of bonds.
Problem 1 Explain the ionic bonds, covalent bonds and metallic bonds and give one example for each type of bonds. Ionic Bonds Two neutral atoms close to each can undergo an ionization process in order
More informationLaser Based Micro and Nanoscale Manufacturing and Materials Processing
Laser Based Micro and Nanoscale Manufacturing and Materials Processing Faculty: Prof. Xianfan Xu Email: xxu@ecn.purdue.edu Phone: (765) 494-5639 http://widget.ecn.purdue.edu/~xxu Research Areas: Development
More informationTypes of Epitaxy. Homoepitaxy. Heteroepitaxy
Epitaxy Epitaxial Growth Epitaxy means the growth of a single crystal film on top of a crystalline substrate. For most thin film applications (hard and soft coatings, optical coatings, protective coatings)
More informationNanoelectronics 09. Atsufumi Hirohata Department of Electronics. Quick Review over the Last Lecture
Nanoelectronics 09 Atsufumi Hirohata Department of Electronics 12:00 Wednesday, 4/February/2015 (P/L 006) Quick Review over the Last Lecture ( Field effect transistor (FET) ): ( Drain ) current increases
More informationOptical Properties of Zn(O,S) Thin Films Deposited by RF Sputtering, Atomic Layer Deposition, and Chemical Bath Deposition
Optical Properties of Zn(O,S) Thin Films Deposited by RF Sputtering, Atomic Layer Deposition, and Chemical Bath Deposition Preprint Jian Li National Renewable Energy Laboratory and Colorado School of Mines
More informationSolid-State Physics: The Theory of Semiconductors (Ch. 10.6-10.8) SteveSekula, 30 March 2010 (created 29 March 2010)
Modern Physics (PHY 3305) Lecture Notes Modern Physics (PHY 3305) Lecture Notes Solid-State Physics: The Theory of Semiconductors (Ch. 10.6-10.8) SteveSekula, 30 March 2010 (created 29 March 2010) Review
More informationMolecular Spectroscopy
Molecular Spectroscopy UV-Vis Spectroscopy Absorption Characteristics of Some Common Chromophores UV-Vis Spectroscopy Absorption Characteristics of Aromatic Compounds UV-Vis Spectroscopy Effect of extended
More informationExciton Diffusion. Exciton Diffusion
Exciton Diffusion Exciton Energy transfer Exciton Diffusion. Photoluminescence measurement. Photocurrent measurement Handout on Photocurrent Response: Bulovic and Forrest., Chemical Physics 210, 13 (1996).
More informationControlling Gold Nanoparticles with Atomic Precision: Synthesis and Structure Determination
Controlling Gold Nanoparticles with Atomic Precision: Synthesis and Structure Determination Huifeng Qian Department of Chemistry, Carnegie Mellon University, USA Advisor: Prof. Rongchao Jin Background
More information1 The water molecule and hydrogen bonds in water
The Physics and Chemistry of Water 1 The water molecule and hydrogen bonds in water Stoichiometric composition H 2 O the average lifetime of a molecule is 1 ms due to proton exchange (catalysed by acids
More informationSingle Defect Center Scanning Near-Field Optical Microscopy on Graphene
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Single Defect Center Scanning Near-Field Optical Microscopy on Graphene J. Tisler, T. Oeckinghaus, R. Stöhr, R. Kolesov, F. Reinhard and J. Wrachtrup 3. Institute
More informationReflection Electron Microscopy and Spectroscopy for Surface Analysis
Reflection Electron Microscopy and Spectroscopy for Surface Analysis by Zhong Lin Wang 1 Introduction In 1986, E. Ruska was awarded the Nobel Physics Prize for his pioneering work of building the world's
More informationHETEROGENEOUS ELECTROPHOTOCATALYSIS ON NANOSTRUCTURED TiO 2 FOR REFRACTORY POLLUTANTS AND RESISTANT PATHOGENS REMOVAL FROM WATER AND WASTEWATER
DIIAR - Environmental Engineering Section HETEROGENEOUS ELECTROPHOTOCATALYSIS ON NANOSTRUCTURED TiO 2 FOR REFRACTORY POLLUTANTS AND RESISTANT PATHOGENS REMOVAL FROM WATER AND WASTEWATER SIDISA Summer School
More informationNovel inkjettable copper ink utilizing processing temperatures under 100 degrees C without the need of inert atmosphere
Novel inkjettable copper ink utilizing processing temperatures under 100 degrees C without the need of inert atmosphere Printed Electronics Europe April 7-8, 2009 Dresden, Germany Dr. Zvi Yaniv Applied
More informationSolar Energy Engineering
Online Training Modules in Photovoltaics Solar Energy Engineering Starting June 2, 2014 the University of Freiburg in cooperation with Fraunhofer will be offering free special training modules in Solar
More informationSpin-Dependent Processes in Organic Devices
Spin-Dependent Processes in Organic Devices Dissertation to obtain the academic degree Dr. rer. nat. submitted to the Departement of Physics of Freie Universität Berlin by: Sebastian Schaefer Berlin, 2010
More informationPlate waves in phononic crystals slabs
Acoustics 8 Paris Plate waves in phononic crystals slabs J.-J. Chen and B. Bonello CNRS and Paris VI University, INSP - 14 rue de Lourmel, 7515 Paris, France chen99nju@gmail.com 41 Acoustics 8 Paris We
More informationLight management for photovoltaics. Ando Kuypers, TNO Program manager Solar
Light management for photovoltaics Ando Kuypers, TNO Program manager Solar Global energy consumption: 500 ExaJoule/Year Solar irradiation on earth sphere: 5.000.000 ExaJoule/year 2 Capturing 0,01% covers
More informationg 0 = 3 ev Linear a = 0.246nm. constant velocity g 0 ~ 3 ev 0.334nm Interlayer g 1 ~ 0.4 ev Massive Effective mass: Graphene monolayer-bilayer junction Theoretical studies Nakanishi, Koshino, Ando, PRB
More informationPolarization Dependence in X-ray Spectroscopy and Scattering. S P Collins et al Diamond Light Source UK
Polarization Dependence in X-ray Spectroscopy and Scattering S P Collins et al Diamond Light Source UK Overview of talk 1. Experimental techniques at Diamond: why we care about x-ray polarization 2. How
More informationElectron Orbits. Binding Energy. centrifugal force: electrostatic force: stability criterion: kinetic energy of the electron on its orbit:
Electron Orbits In an atom model in which negatively charged electrons move around a small positively charged nucleus stable orbits are possible. Consider the simple example of an atom with a nucleus of
More informationElectron spectroscopy Lecture 1-21. Kai M. Siegbahn (1918 - ) Nobel Price 1981 High resolution Electron Spectroscopy
Electron spectroscopy Lecture 1-21 Kai M. Siegbahn (1918 - ) Nobel Price 1981 High resolution Electron Spectroscopy 653: Electron Spectroscopy urse structure cture 1. Introduction to electron spectroscopies
More informationFabrication and Characterization of Nanostructured Silicon Films For Photovoltaic Applications. Kai Wang
Fabrication and Characterization of Nanostructured Silicon Films For Photovoltaic Applications by Kai Wang A thesis submitted to the Faculty of Graduated and Postdoctoral Affairs in partial fulfillment
More informationPhotovoltaics photo volt Photovoltaic Cells Crystalline Silicon Cells Photovoltaic Systems
1 Photovoltaics Photovoltaic (PV) materials and devices convert sunlight into electrical energy, and PV cells are commonly known as solar cells. Photovoltaics can literally be translated as light-electricity.
More informationNORGES TEKNISK- NATURVITENSKAPELIGE UNIVERSITET INSTITUTT FOR FYSIKK. Eksamen i Emne TFY4220 Faste Stoffers Fysikk
Page of 5 NORGES TEKNISK- NATURVITENSKAPELIGE UNIVERSITET INSTITUTT FOR FYSIKK Fagleg kontakt under eksamen: Institutt for fysikk, Gløshaugen Professor Steinar Raaen, 4896758 Eksamen i Emne TFY40 Faste
More informationLight Trapping in Organic Solar Cells
Dielectric nanostructures for broadband light trapping in organic solar cells Aaswath Raman, Zongfu Yu, and Shanhui Fan Ginzton Laboratory, Stanford University, Stanford, California 9435, USA shanhui@stanford.edu
More information