Eric Hoke

Associate Director
Center for Advanced Molecular Photovoltaics, Stanford University

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Mailing
Address
McCullough Building 220
476 Lomita Mall
Stanford, CA 94305
Phone 650-721-1833
E-Mail erichoke@stanford.edu



Metal halide perovskite photovoltaics are relatively new photovoltaic technology that has recently achieved power conversion efficiencies over 20% at the laboratory scale after only a few years of research and development. Perovskite photovoltaics offer the potential of providing solar energy at a significantly lower cost than conventional technologies, as they can be mass produced in a fashion similar to newspaper printing and are made from inexpensive, abundant materials. Perovskite photovoltaics can obtain voltages of over 1.1V- higher than other polycrystalline solar cells. This opens the possibility of inexpensively laminating perovskite devices on top of silicon or CIGS solar cells, creating a tandem (i.e. multijunction solar cell) solar cell with a power conversion efficiency of 30% or more. However, today's perovskite solar cells are not very stable or reliable. Devices are highly sensitive to moisture and typically exhibit hysteresis. Improving the stability of the perovskite to light, electromigration and moisture will likely be necessary for commercialization of this technology.

During my PhD I investigated the recombination mechanisms which place practical limitations of how much current and voltage can be produced by polymer-fullerene based organic photovoltaics with Prof. Michael McGehee. I also helped engineer a new device architecture for dye sensitized solar cells that mimics photosynthesis by using multiple dyes which relay energy to a central sensitizing dye by a mechanism known as Forster resonant energy transfer. Prior to Stanford, I researched light-matter interactions with Eric Mazur's photonics lab at Harvard, granular physics with Heinrich Jaeger at the University of Chicago, and wrote my Masters Thesis on nanoparticle (CdTe)-polymer blend solar cells at Cambridge University with Neil Greenham.


Research Interests

  • Voltage losses in solar cells
  • Perovskite photovoltaics and tandem solar cells
  • Ionic stability of halide perovskites
  • Advanced metrologies for the characterization of photovoltaic materials
  • Organic electronics

  • Education

    PhD, Applied Physics (2012)
    McGehee Group, Center for Advanced Molecular Photovoltaics
    Stanford University
    Stanford, CA

    MPhil, Physics (2007)
    Optoelectronics Group, Cavendish Laboratory
    University of Cambridge
    Cambridge, UK
    Thesis: Charge and Energy Transfer in Nanocrystal-Polymer Blends (pdf)

    B.A., Summa Cum Laude, Chemistry and Physics (2006)
    Harvard University
    Cambridge, MA


    Fellowships

    Hertz Foundation Fellowship (2007-2012)
    National Science Foundation GRFP Fellowship (2007-2010)
    Stanford Graduate Fellowship (2007-2012)
    Herchel Smith Harvard Scholarship to Cambridge University (2006-2007)


    Selected Publications

    A complete listing can be found here.
    Reversible photo-induced trap formation in mixed halide hybrid perovskites for photovoltaics. Eric T. Hoke, et al. Chemical Science, 6 (2015) 613. (pdf)

    Hysteresis and transient behavior in current–voltage measurements of hybrid-perovskite absorber solar cells. Eva L. Unger, Eric T. Hoke, et al. Energy and Enviromental Science, 7 (2014) 3690. (pdf)

    Probing carrier lifetimes in photovoltaic materials using subsurface two-photon microscopy. Edward S. Barnard, Eric T. Hoke, et. al. Scientific Reports, 3 (2013) 2098. (pdf)

    Recombination in polymer:fullerene solar cells with open circuit voltages approaching and exceeding 1.0 V. Eric T. Hoke, et al. Advanced Energy Materials, 3 (2013) 220. (pdf)

    The role of electron affinity in determining whether fullerenes catalyze or inhibit photo-oxidation of polymers. Eric T. Hoke, et al. Advanced Energy Materials, 2 (2012) 1351. (pdf)

    Morphology-Dependent Trap Formation in High Performance Polymer Bulk Heterojunction Solar Cells. Zach M. Beiley, Eric T. Hoke, et al. Advanced Energy Materials, 1 (2011) 954. (pdf)

    Accounting for Interference, Scattering, and Electrode Absorption to Make Accurate Internal Quantum Efficiency Measurements in Organic and Other Thin Solar Cells. George F. Burkhard, Eric T. Hoke, and Michael D. McGehee, Advanced Materials, 22 (2010) 3293. (pdf)

    Modeling the efficiency of Förster resonant energy transfer from energy relay dyes in dye-sensitized solar cells. Eric T. Hoke, Brian E. Hardin, and Michael D. McGehee, Optics Express, 18 No. 4 (2010) 3893. (pdf)

    Incomplete Exciton Harvesting from Fullerenes in Bulk Heterojunction Solar Cells. George F. Burkhard, Eric T. Hoke, Shawn R. Scully, and Michael D. McGehee, Nanoletters, 9 (2009) 4037. (pdf)

    Increased light harvesting in dye-sensitized solar cells with energy relay dyes. Brian E. Hardin, Eric T. Hoke, et al., Nature Photonics, 3 (2009) 406. (pdf)

    Courses Taught

    MatSci 343: Organic Electronics (2013) (2014) Not offered 2015.

    Races!

    Boston Marathon
    April 19, 2004
    3:55:29 (unofficial)
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    Boston Marathon
    April 18, 2005
    3:27:23
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    Philadelphia Distance Run (Half)
    September 18, 2005
    1:27:32
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    Boston Marathon
    April 17, 2006
    3:25:56
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    Bay to Breakers (12K)
    May 18, 2008
    58:15
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    San Francisco Marathon
    August 3, 2008
    3:28:21
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    Pacific Grove Olympic Distance Triathlon
    September 12, 2009
    43:38 swim / 1:19:15 bike / 44:37 run
    2:56:55 overall
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