|| M. LLC, “The end of fossil fuels,” (2016).|
 F. Hartmut and H. R. Khan, Handbook of Thin-Film Technology
(Springer-Verlag, Berlin, 2015).
 R. Eason, Pulsed laser deposition of thin films: applications-led
growth of functional materials, first edition (John Wiley and
Sons, Inc., 2006).
 R. K. Singh and J. Narayan, “Pulsed-laser evaporation technique
for deposition of thin films: Physics and theoretical model,” Phy
Rev B 41, 8843–1–13 (1990).
 R. Kelly and B. Braren, “On the direct observation of the gasdynamics
of laser-pulse sputtering of polymers,” Appl Phys B
53, 160–169 (1991).
 S. I. Anisimov, B. S. Lukyanchuk, and A. Luches, “An analytical
model for three-dimensional laser plume expansion into vacuum
in hydrodynamic regime,” Appl Surf Sci 2, 96–98 (1996).
 T. Donnelly, J. G. Lunney, S. Amoruso, R. Bruzzese, X. Wang,
and X. Ni, “Dynamics of the plumes produced by ultrafast laser
ablation of metals,” J Appl Phy 108, 043,309–1–13 (2010).
 C. Phipps, ed., Laser Ablation and its Applications (SpringerVerlag,
 S. Amoruso, R. Bruzzese, N. Spinelli, and R. Velotta, “Characterization
of laser-ablation plasmas,” J Phys B 32, R131–R172
 K. D. Kreuer, Fuel Cells: Selected Entries from the Encyclopedia
of Sustainability Science and Technology (Springer New York,
 H. Tsuchiyaa and O. Kobayashib, “Mass production cost of pem
fuel cell by learning curve,” Int J Hydrogen Energy 29, 985–990
 K. Strickland, E. Miner, Q. Jia, U. Tylus, N. Ramaswamy,
W. Liang, M. T. Sougrati, F. Jaouen, and S. Mukerjee, “Highly
active oxygen reduction non-platinum group metal electrocatalyst
without direct metal?nitrogen coordination,” Nat. Comm 6,
 H. M. Barkholtz, L. Chong, Z. B. Kaiser, T. Xu, and D.-J. Liu,
“Enhanced performance of non-pgm catalysts in air operated
pem-fuel cells,” Int J Hydrogen Energy (2016).
 Z. Q. Tian, S. H. Lim, C. K. Poh, Z. Tang, Z. Xia, Z. Luo, P. K.
Shen, D. Chua, Y. P. Feng, Z. Shen, and J. Lin, “A highly orderstructured
membrane electrode assembly with vertically aligned
carbon nanotubes for ultra-low pt loading pem fuel cells,” Adv.
Ene. Mat 1, 1205–1214 (2011).
 S. Y. Huang, P. Ganesan, S. Park, and B. N. Popov, “Development
of a titanium dioxide-supported platinum catalyst with
ultrahigh stability for polymer electrolyte membrane fuel cell
applications,” J Am Chem Soc. 131, 13,898–13,899 (2009).
 X. X. Wang, Z. H. Tan, M. Zeng, and J. N. Wang, “Carbon
nanocages: A new support material for pt catalyst with remarkably
high durability,” Sci Rep 4, 4437 (2014).
 S. Murata, M. Imanishi, S. Hasegawa, and R. Namba, “Vertically
aligned carbon nanotube electrodes for high current density operating
proton exchange membrane fuel cells,” J Power Sources
253, 104–113 (2014).
 D. Sebastian, J. C. Calderon, J. A. Gonzalez-Exposito, E. Pastor,
M. V. Martnez-Huerta, I. Suelves, R. Moliner, and M. J.
Lazaro, “Influence of carbon nanofiber properties as electrocatalyst
support on the electrochemical performance for pem fuel
cells,” Int J Hydrogen Energy 35, 9934–9942 (2010).
 E. Yli-Rantala, A. Pasanen, P. Kauranen, V. Ruiz, M. Borghei,
E. Kauppinen, and E. Skou, “Graphitised carbon nanofibres as
catalyst support for pemfc,” Fuel Cells 11, 715–725 (2011).
 M. S. Wilson, J. A. Valerio, and S. Gottesfeld, “Low platinum
loading electrodes for polymer electrolyte fuel cells fabricated
using thermoplastic ionomers,” Electrochem Acta 40, 355–363
 S. Litster and G. McLean, “Pem fuel cell electrodes,” J Power
Sources 130, 61–76 (2004).
 M. S. Wilson and S. Gottesfeld, “High performance catalyzed
membranes of ultra low pt loadings for polymer electrolyte fuel
cells,” J Electrochem Soc 139, L28–L30 (1992).
 E. J. Taylor, E. B. Anderson, and N. R. K. Vilambi, “Preparation
of high platinum utilization gas diffusion electrodes for
proton?exchange?membrane fuel cells,” J Electrochem Soc 139,
 S. Cuynet, A. Caillard, T. Lecas, J. Bigarr`e, P. Buvat, and
P. Brault, “Deposition of Pt inside fuel cell electrodes using high
power impulse magnetron sputtering,” J Phys D: Appl Phys 47,
 M. Cavarroc, A. Ennadjaoui, M. Mougenot, P. Brault, R. Escalier,
Y. Tessier, J. Durand, S. Rouald`es, T. Sauvage, and
C. Coutanceau, “Performance of plasma sputtered fuel cell electrodes
with ultra-low Pt loadings,” Electrochem Comm 11, 859–
 M. S. Cogenli, S. Mukerjee, and A. B. Yurtcan, “Membrane
electrode assembly with ultra low platinum loading for cathode
electrode of PEM fuel cell by using sputter deposition,” Fuel
Cells 15, 288–297 (2015).
 M. A. Raso, I. Carrillo, E. Mora, E. Navarro, M. A. Garcia,
and T. J. Leo, “Electrochemical study of platinum deposited by
electron beam evaporation for application as fuel cell electrodes,”
Int J Hydrogen Energy 39, 5301–5308 (2014).
 M. S. Saha, A. F. Gull`a, R. J. Allen, and S. Mukerjee, “High
performance polymer electrolyte fuel cells with ultra-low Pt loading
electrodes prepared by dual ion-beam assisted deposition,”
Electrochim Acta 51, 4680–4692 (2006).
 N. Cunningham, E. Irissou, M. Lefevre, M. C. Denis, D. Guay,
and J. P. Dodelet, “Pemfc anode with very low pt loadings using
pulsed laser deposition,” Electrochem. Solid-State Lett. 6,
 T. W. Huang, H. Qayyum, G. R. Lin, S. Y. Chen, and
C. J. Tseng, “Production of high-performance and improveddurability
Pt-catalyst/support for proton-exchange-membrane
fuel cells with pulsed laser deposition,” J Phys D: Appl Phys
49, 255,601 (2016).
 H. Qayyum, C.-J. Tseng, T.-W. Huang, and S. yuan Chen,
“Pulsed laser deposition of platinum nanoparticles as a catalyst
for high-performance pem fuel cells,” Catalysts 6 (2016).
 T. Nakakubo, M. Shibata, and K. Yasuda, “Membrane electrode
assembly for proton exchange membrane fuel cells prepared by
sputter deposition in air and transfer method,” J Electrochem
Soc 152, A2316–A2322 (2005).
 D. Riabinina, E. Irissou, B. L. Drogoff, M. Chaker, and D. Guay,
“Influence of pressure on the Pt nanoparticle growth modes during
pulsed laser ablation,” J Appl Phys 108, 034,322–1–034,322–
 C. Hamel, S. Garbarino, E. Irissou, F. Laplante, M. Chaker, and
D. Guay, “Influence of the velocity of Pt ablated species on the
structural and electrocatalytic properties of Pt thin films,” Int
J Hydrogen Energy 35, 8486–8493 (2010).
 D. Wang, H. L. Xin, R. Hovden, H. Wang, Y. Yu, D. A. Muller,
F. J. DiSalvo, and H. D. Abruna, “Structurally ordered intermetallic
platinum cobalt core shell nanoparticles with enhanced
activity and stability as oxygen reduction electrocatalysts,” Nat
Mat 12, 81–87 (2013).
 P. Strasser, S. Koh, T. Anniyev, J. Greeley, K. More, C. Yu,
Z. Liu, S. Kaya, D. Nordlund, H. Ogasawara, M. F. Toney, and
A. Nilsson, “Lattice-strain control of the activity in dealloyed
core?shell fuel cell catalysts,” Nat Chem 12, 454–460 (2010).
 “Advanced cathode catalysts and supports for pem fuel cells,”
Annual Merit Review DOE Hydrogen and Fuel Cells and Vehicle
Technologies Programs, Washington, DC (2009).
 A. Kongkanand and M. F. Mathias, “The priority and challenge
of high-power performance of low-platinum proton-exchange
membrane fuel cells,” J Phys Chem Lett 7, 1127–1137 (2016).
 Y. Xing, “Synthesis and electrochemical characterization
of uniformly-dispersed high loading pt nanoparticles on
sonochemically-treated carbon nanotubes,” J Phys Chem B 108,
 P. Ramesh, M. E. Itkis, J. M. Tang, and R. C. Haddon, “Swntmwnt
hybrid architecture for proton exchange membrane fuel
cell cathodes,” J Phys Chem C 112, 9089–9094 (2008).
 W. Zhang, P. Sherrell, A. I. Minett, J. M. Razal, and J. Chen,
“Carbon nanotube architectures as catalyst supports for proton
exchange membrane fuel cells,” Energy Environ. Sci. 3, 1286–
 Z. M. Wang, Self-Assembled Quantum Dots (Springer New York,
 B. J. Riel, “An introduction to self-assembled quantum dots,”
Am. J. Phys. 76, 750–757 (2008).
 A. L. Efros, D. J. Lockwood, and L. Tsybeskov, Semiconductor
Nanocrystals: From Basic Principles to Applications (Springer
 A. Baskaran and P. Smerekal, “Mechanisms of stranskikrastanov
growth,” J Appl Phys. 111, 044,321–1–6 (2012).
 A. Alkhatib and A. Nayfeh, “A complete physical germaniumon-silicon
quantum dot self-assembly process,” Sci. Rep. 3, 1–4
 M. Borgstr‥om, V. Zela, and W. Seifert, “Arrays of Ge islands
on Si(001) grown by means of electron-beam pre-patterning,”
Nanotechnology 14, 264–267 (2003).
 A. Karmous, A. Cuenat, A. Ronda, and I. Berbezie, “Ge dot
qrganization on Si substrates patterned by focused ion beam,”
Appl. Phys. Lett. 85, 6401–6403 (2004).
 A. Portavoce, A. Ronda, and I. Berbezier, “Sb-surfactant mediated
growth of Ge nanostructures,” Mat. Sci. Eng. B 89, 205–210
 A. Beyer, E. M‥uller, H. Sigg, S. Stutz, D. Gr‥utzmacher,
O. Leifeld, and K. Ensslin, “Size control of carbon-induced Ge
quantum dots,” Appl. Phys. Lett. 77, 3218–3220 (2000).
 Y. Wakayamaa, L. V. Sokolovb, N. Zakharovc, P. Wernerc, and
U. G‥oselec, “Precise control of size and density of self-assembled
Ge dot on Si (100) by carbon-induced strain-engineering,” Appl.
Surf. Sci. 216, 419–423 (2003).
 A. A. Shklyaev, M. Shibata, and M. Ichikawa, “High-density
ultrasmall epitaxial Ge islands on Si (111) surfaces with a SiO2
coverage,” Phys. Rev. B 62, 1540–1543 (2000).
 C. Dais, G. Mussler, T. Fromherz, E. M‥uller, H. H. Solak, and
D. Gr‥utzmacher, “SiGe quantum dot crystals with periods down
to 35 nm,” Nanotechnology 26, 255,302 (2015).
 R. F. Wood and G. E. Giles, “Macroscopic theory of pulsed-laser
annealing. i. thermal transport and melting,” Phys Rev B. 23,
 N. Nickel, Laser Crystallization of Silicon - Fundamentals to Devices
 G. Han, Y. Zeng, Y. Liu, J. Yu, B. Cheng, and H. Yang, “Small
SiGe quantum dots obtained by excimer laser annealing,” J.
Cryst. Growth 310, 3746–3751 (2008).
 A. O. Er and H. E. Elsayed-Ali, “Excitation-induced germanium
quantum dot formation on Si (100) - (2×1),” J. Appl. Phys. 108,
 A. P. D. Pino, E. Gyorgy, I. C. Marcus, J. Roqueta, and
M. I. Alonso, “Effects of pulsed laser radiation on epitaxial selfassembled
Ge quantum dots grown on Si substrates,” Nanotechnology
22, 295,304 (2011).
 C. M. Clegg and H. Yang, “Guided assembly of quantum dots
through selective laser heating,” Sol. Energ. Mat. Sol. C. 108,
 D. Qi, X. Li, P. Wang, S. Chen, W. Huang, C. Li, K. Huang, and
H. Lai, “Evolution of laser-induced specific nanostructures on
sige compounds via laser irradiation intensity tuning,” Photon.
J. 6, 252–255 (2014).
 A. Medvid, P. Onufrijevs, G. Mozolevskis, E. Dauksta, and
R. Rimsa, “Two-stage model of nanocone formation on a sur-
face of elementary semiconductors by laser radiation,” Nanoscale
Research Letters . 7, 428 (2012).
 H. Luth, Solid Surfaces, Interfaces and Thin Films, fourth edition
(Springer-Verlag, Berlin, 2001).
 J. Zhang, PEM Fuel Cell Electrocatalysts and Catalyst Layers
(Springer-Verlag, London, 2008).
 M. Ciureanu and R. Roberge, “Electrochemical impedance study
of pem fuel cells. experimental diagnostics and modeling of air
cathodes,” J Phys Chem B 105, 3531–3539 (2001).
 A. Brouzgou, S. Q. Song, and P. Tsiakaras, “Low and nonplatinum
electrocatalysts for PEMFCs: Current status, challenges
and prospects,” Appl Catal B: Environmental 127, 371–
 C. Wang, M. Waje, X. Wang, J. M. Tang, R. C. Haddon, and
 H. Xu, E. Brosha, F. Garzon, C. Johnston, F. Uribe, M. Wilson,
and B. S. Pivovar, “Electrochemical characterization of catalyst
utilization in half and fuel cells,” 212th ECS Meeting p. p428
 D. Gruber, N. Ponath, J. Muller, and F. Lindstaedt, “Sputterdeposited
ultra-low catalyst loadings for pem fuel cells,” J. Power
Sources 150, 67–72 (2005).
 B. Schwanitz, H. Schulenburg, M. Horisberger, A. Wokaun, and
G. Scherer, “Stability of ultra-low pt anodes for polymer electrolyte
fuel cells prepared by magnetron sputtering,” Electrocatal
2, 35–41 (2011).
 Y. C. Hsueh, C. C. Wang, C. C. Kei, Y. H. Lin, C. Liu, and
T. P. Perng, “Fabrication of catalyst by atomic layer deposition
for high specific power density proton exchange membrane fuel
cells,” J. Catal. 294, 63–68 (2012).
 T. Shu, D. Dang, D. W. Xu, R. Chen, S. J. Liao, C. T. Hsieh,
A. Su, H. Y. Song, and L. Du, “High-performance MEA prepared
by direct deposition of platinum on the gas diffusion layer using
an atomic layer deposition technique,” Electrochim Acta 177,
 B. T. Tsai, C. J. Tseng, Z. S. Liu, C. H. Wang, C. I. Lee, C. C.
Yang, and S. K. Lo, “Effects of flow field design on the performance
of a PEM fuel cell with metal foam as the flow distributor,”
Int J Hydrogen Energy 37, I3060–I3066 (2012).
 C. J. Tseng, B. T. Tsai, Z. S. Liu, T. C. Cheng, W. C. Chang,
and S. K. Lo, “A PEM fuel cell with metal foam as flow distributor,”
Energ Convers Manage 62, 14–21 (2012).
 A. L. Patterson, “The scherrer formula for x-ray particle size
determination,” Phys. Rev. 56, 978–82 (1939).
 J. Ma, A. Habrioux, C. Morais, A. Lewera, W. Vogel, Y. VerdeGomez,
G. Ramos-Sanchez, P. B. Balbuena, and N. AlonsoVante,
“Spectroelectrochemical probing of the strong interaction
between platinum nanoparticles and graphitic domains of
carbon,” ACS Catal. 3, 1940–50 (2013).
 P. T. Yu, W. Gu, R. Makharia, F. T. Wagner, and H. A.
Gasteiger, “The impact of carbon stability on PEM fuel cell
startup and shutdown voltage degradation,” ECS Trans. 3, 797–
 S. Zhang, X. Z. Yuan, J. N. C. Hin, H. Wang, K. A. Friedrich,
and M. Schulze, “A review of platinum-based catalyst layer
degradation in proton exchange membrane fuel cells,” J. Power
Sources 194, 588–600 (2009).
 P. Lespade, R. Al-Jishi, and M. S. Dresselhaus, “Model for raman
scattering from incompletely graphitized carbons,” Carbon
20, 427–31 (1982).
 L. Zou, B. Huang, Y. Huang, Q. Huang, and C. Wang, “An investigation
of heterogeneity of the degree of graphitization in
carbon?carbon composites,” Mater. Chem. Phys. 82, 654–62
 W. Mr`oz, B. Budner, W. Tokarz, P. Piela, and M. L. K.
Pawlowski, “Ultra-low-loading pulsed-laser-deposited platinum
catalyst films for polymer electrolyte membrane fuel cells,” J
Power Sources 273, 885–893 (2015).
 R. O. Hayre, S. J. Lee, S. W. Cha, and F. B. Prinz, “A sharp
peak in the performance of sputtered platinum fuel cells at ultralow
platinum loading,” J Power Sources 109, 483–493 (2002).
 M. K. Debe, “Electrocatalyst approaches and challenges for automotive
fuel cells,” Nature 486, 43–51 (2012).
 J. M. D. Rodr`?guez, J. A. H. Meli`an, and J. P. Pe?na, “Determination
of the real surface area of Pt electrodes by hydrogen
adsorption using cyclic voltammetry,” J Chem Educ 77, 1195–
 E. Fabbri, S. Taylor, A. Rabis, P. Levecque, O. Conrad, R. Kotz,
and T. J. Schmidt, “The effect of platinum nanoparticle distribution
on oxygen electroreduction activity and selectivity,” Chem
Cat Chem 6, 1410–1418 (2014).
 X. Yuan, H. Wang, J. C. Sun, and J. Zhang, “AC impedance
technique in PEM fuel cell diagnosis-A review,” Int J Hydrogen
Energy 32, 4365–4380 (2007).
 J. Zhang, C. Song, J. Zhang, R. Baker, and L. Zhang, “Understanding
the effects of backpressure on PEM fuel cell reactions
and performance,” J Electroanal Chem 688, 130–136 (2013).
 J. Zhang, H. Li, and J. Zhang, “Effect of operating backpressure
on PEM fuel cell performance,” ECS Trans 19, 65–76 (2009).
 F. F. Onana, N. Guillet, and A. M. AlMayouf, “Modified pulse
electrodeposition of Pt nanocatalyst as high-performance electrode
for PEMFC,” J Power Sources 271, 401–405 (2014).
 H. Yu, J. M. Roller, W. E. Mustain, and R. Maric, “Influence of
the ionomer/carbon ratio for low-Pt loading catalyst layer prepared
by reactive spray deposition technology,” J Power Sources
283, 84–94 (2015).
 A. Khan, B. K. Nath, and J. Chutia, “Nanopillar structured
platinum with enhanced catalytic utilization for electrochemical
reactions in PEMFC,” Electrochim Acta 146, 171–177 (2014).
 H. N. Su, S. J. Liao, T. Shu, and H. L. Gao, “Performance
of an ultra-low platinum loading membrane electrode assembly
prepared by a novel catalyst-sprayed membrane technique,” J
Power Sources 195, 756–761 (2010).
 Y. Yuan, J. A. Smith, G. Goenaga, D. J. Liu, Z. Luo, and J. Liu,
“Platinum decorated aligned carbon nanotubes: electrocatalyst
for improved performance of proton exchange membrane fuel
cells,” J Power Sources 196, 6160–6167 (2011).
 T. A. Greszler, D. Caulk, and P. Sinha, “The impact of platinum
loading on oxygen transport resistance,” J Electrochem Soc 159,
 A. Z. Weber and A. Kusoglu, “Unexplained transport resistances
for low-loaded fuel-cell catalyst layers,” J Mater Chem A 2,
 Y. Zhou, G. Lin, A. J. Shih, and S. J. Hu, “Assembly pressure
and membrane swelling in pem fuel cells,” J Power Sources 192,
 F. Bauer, S. Denneler, and M. Willert-Porada, “Influence of temperature
and humidity on the mechanical properties of nafion
117 polymer electrolyte membrane,” J Polym Sci B Polym Phys.
43, 786–795 (2005).
 C. J. Tseng, S. T. Lo, S. C. Lo, and P. P. Chu, “Characterization
of Pt-Cu binary catalysts for oxygen reduction for fuel cell
applications,” Mater Chem Phys 100, 385–390 (2006).
 B. J. Su, K. W. Wang, T. C. Cheng, and C. J. Tseng, “Preparation
of PtSn/C electrocatalysts with improved activity and durability
toward oxygen reduction reaction by alcohol-reduction
process,” Mater Chem Phys 135, 395–400 (2012).
 K. L. Wang, D. Cha, J. Liu, and C. Chen, “Ge/Si self-assembled
quantum dots and their optoelectronic device applications,”
Proc IEEE 95, 1866–1883 (2007).
 Z. Liu, T. Zhou, L. Li, Y. Zuo, C. He, C. Li, C. Xue, B. Cheng,
and Q. Wang, “Ge/Si quantum dots thin film solar cells,” Appl.
Phys. Lett. 103, 082,101 (2013).
 H. T. Chang, S. Y. Wang, and S. W. Lee, “Designer Ge/Si composite
quantum dots with enhanced thermoelectric properties,”
Nanoscale 6, 3593–3598 (2014).
 D. J. Eaglesham and M. Cerullo, “Dislocation-free StranskiKrastanow
growth of Ge on Si(100),” Phys. Rev. Lett. 64, 1943–
 A. I. Yakimov, A. V. Dvurechenski, A. I. Nikiforov, S. V.
Chaoekovski, and S. A. Tiis, “Ge/Si photodiodes with embedded
arrays of Ge quantum dots for the near infrared (1.3–1.5
μm) region,” Semiconductors 37, 1383–1388 (2003).
 S. M. Sze, in “Physics of Semiconductor Devices,” (John Wiley
and Sons, New York, 1981).
 J. A. Floro, M. B. Sinclair, E. Chason, L. B. Freund, R. D.
Twesten, R. Q. Hwang, and G. A. Lucadamo, “Novel SiGe island
coarsening kinetics: Ostwald ripening and elastic interactions,”
Phys. Rev. Lett. 84, 701–704 (2000).
 A. V. Kolobov, “Raman scattering from Ge nanostructures
grown on Si substrates: Power and limitations,” J. Appl. Phys.
87, 2926–2930 (2000).
 M. Fujii, S. Hayashi, and K. Yamamoto, “Growth of Ge microcrystals
in SiO2 thin film matrices: A Raman and electron
microscopic study,” Jpn. J. Appl. Phys. 30, 687–694 (1991).
 X. Deng, J. D. Weil, and M. Krishnamurthy, “Temperature dependence
of SiGe coherent island formation on Si (100): Anomalous
reentrant behavior,” Phys. Rev. Lett. 80, 4721–4724 (1998).
 M. Gavelle, E. M. Bazizi, E. Scheid, P. F. Fazzini, F. Cristiano,
C. Armand, W. Lerch, S. Paul, Y. Campidelli, and A. Halimaoui,
“Detailed investigation of GeSi interdiffusion in the full range of
Si 1?x Ge x (0 ? x ? 1) composition,” J. Appl. Phys. 104,