[1] Jackson P, Hariskos D, Lotter E, Paetel S, Wuerz R, Menner R, Wischmann W, Powalla M. New world record efficiency for Cu(In, Ga)Se2 thin-film solar cells beyond 20%. Progress in Photovoltaics: Research and Applications, 2011, 19(7): 894-897
[2] Semonin O E, Luther J M, Choi S, Chen H Y, Gao J, Nozik A J, Beard M C. Peak external photocurrent quantum efficiency exceeding 100% via MEG in a quantum dot solar cell. Science, 2011, 334(6062): 1530-1533
[3] Ip A H, Thon SM, Hoogland S, Voznyy O, Zhitomirsky D, Debnath R, Levina L, Rollny L R, Carey G H, Fischer A, Kemp KW, Kramer I J, Ning Z, Labelle A J, Chou K W, Amassian A, Sargent E H. Hybrid passivated colloidal quantum dot solids. Nature Nanotechnology, 2012, 7: 577- 582
[4] Li G, Zhu R, Yang Y. Polymer solar cells. Nature Photonics, 2012, 6 (3): 153-161
[5] Chung I, Lee B, He J, Chang R P H, Kanatzidis M G. All-solid-state dye-sensitized solar cells with high efficiency. Nature, 2012, 485(7399): 486-489
[6] Debnath R, Bakr O, Sargent E H. Solution-processed colloidal quantum dot photovoltaics: a perspective. Energy & Environmental Science, 2011, 4(12): 4870-4881
[7] Kramer I J, Sargent E H. Colloidal quantum dot photovoltaics: a path forward. ACS Nano, 2011, 5(11): 8506-8514
[8] Tang J, Sargent E H. Infrared colloidal quantum dots for photovoltaics: fundamentals and recent progress. Advanced Materials (Deerfield Beach, Fla.), 2011, 23(1): 12-29
[9] Hines M A, Scholes G D. Colloidal PbS nanocrystals with sizetunable near-infrared emission: observation of post-synthesis selfnarrowing of the particle size distribution. Advanced Materials, 2003, 15(21): 1844-1849
[10] Henry C H. Limiting efficiencies of ideal single and multiple energy gap terrestrial solar cells. Journal of Applied Physics, 1980, 51(8): 4494-4500
[11] Wise F W. Lead salt quantum dots: the limit of strong quantum confinement. Accounts of Chemical Research, 2000, 33(11): 773-780
[12] Brown A S, Green M A. Detailed balance limit for the series constrained two terminal tandem solar cell. Physica E, Low-Dimensional Systems and Nanostructures, 2002, 14(1-2): 96-100
[13] Nozik A J, BeardMC, Luther JM, Law M, Ellingson R J, Johnson J. C. Semiconductor quantum dots and quantum dot arrays and applications of multiple exciton generation to third-generation photovoltaic solar cells. Chemical Reviews, 2010, 110(11): 6873-6890
[14] McDaniel H, Heil P E, Tsai C L, Kim K K, Shim M. Integration of type II nanorod heterostructures into photovoltaics. ACS Nano, 2011, 5(9): 7677-7683
[15] Johnston K W, Pattantyus-Abraham A G, Clifford J P, Myrskog S H, MacNeil D D, Levina L, Sargent E H. Schottky-quantum dot photovoltaics for efficient infrared power conversion. Applied Physics Letters, 2008, 92(15): 151115
[16] Luther J M, Law M, Beard MC, Song Q, Reese MO, Ellingson R J, Nozik A J. Schottky solar cells based on colloidal nanocrystal films. Nano Letters, 2008, 8(10): 3488-3492
[17] Leschkies K S, Beatty T J, Kang M S, Norris D J, Aydil E S. Solar cells based on junctions between colloidal PbSe nanocrystals and thin ZnO films. ACS Nano, 2009, 3(11): 3638-3648
[18] Barkhouse D A, Debnath R, Kramer I J, Zhitomirsky D, Pattantyus-Abraham A G, Levina L, Etgar L, Gratzel M, Sargent E H. Depleted bulk heterojunction colloidal quantum dot photovoltaics. Advanced Materials, 2011, 23(28): 3134-3138
[19] Kramer I J, Zhitomirsky D, Bass J D, Rice PM, Topuria T, Krupp L, Thon S M, Ip A H, Debnath R, Kim H C, Sargent E H. Ordered nanopillar structured electrodes for depleted bulk heterojunction colloidal quantum dot solar cells. Advanced Materials, 2012, 24(17): 2315-2319
[20] Rath A K, Bernechea M, Martinez L, Konstantatos G. Solutionprocessed heterojunction solar cells based on p-type PbS quantum dots and n-type Bi2 S3 nanocrystals. Advanced Materials, 2011, 23(32): 3712-3717
[21] Rath A K, Bernechea M, Martinez L, de Arquer F P G, Osmond J, Konstantatos G. Solution-processed inorganic bulk nano-heterojunctions and their application to solar cells. Nature Photonics, 2012, 6(8): 529-534
[22] Xu F, Ma X, Haughn C R, Benavides J, Doty M F, Cloutier S G. Efficient exciton funneling in cascaded PbS quantum dot superstructures. ACS Nano, 2011, 5(12): 9950-9957
[23] Kramer I J, Levina L, Debnath R, Zhitomirsky D, Sargent E H. Solar cells using quantum funnels. Nano Letters. 2011, 11(9): 3701-3706
[24] Liu H, Tang J, Kramer I J, Debnath R, Koleilat G I, Wang X, Fisher A, Li R, Brzozowski L, Levina L, Sargent E H. Electron acceptor materials engineering in colloidal quantum dot solar cells. Advanced Materials, 2011, 23(33): 3832-3837
[25] Gao J, Luther JM, Semonin O E, Ellingson R J, Nozik A J, BeardM C. Quantum dot size dependent J-V characteristics in heterojunction ZnO/PbS quantum dot solar cells. Nano Letters, 2011, 11(3): 1002-1008
[26] Gao J, Perkins C L, Luther J M, Hanna M C, Chen H Y, Semonin O E, Nozik A J, Ellingson R J, Beard M C. n-type transition metal oxide as a hole extraction layer in PbS quantum dot solar cells. Nano Letters, 2011, 11(8): 3263-3266
[27] Brown P R, Lunt R R, Zhao N, Osedach T P,Wanger D D, Chang L Y, Bawendi M G, Bulovic V. Improved current extraction from ZnO/PbS quantum dot heterojunction photovoltaics using a MoO3 interfacial layer. Nano Letters, 2011, 11(7): 2955-2961
[28] Jeong K S, Tang J, Liu H, Kim J, Schaefer AW, Kemp K, Levina L, Wang X, Hoogland S, Debnath R, Brzozowski L, Sargent E H, Asbury J B. Enhanced mobility-lifetime products in PbS colloidal quantum dot photovoltaics. ACS Nano, 2012, 6(1): 89-99
[29] Klem E J D, Gregory C W, Cunningham G B, Hall S, Temple D S, Lewis J S. Planar PbS quantum dot/C60 heterojunction photovoltaic devices with 5.2% power conversion efficiency. Applied Physics Letters, 2012, 100(17): 173109
[30] Tang J, Kemp K W, Hoogland S, Jeong K S, Liu H, Levina L, Furukawa M, Wang X, Debnath R, Cha D, Chou K W, Fischer A, Amassian A, Asbury J B, Sargent E H. Colloidal-quantum-dot photovoltaics using atomic-ligand passivation. Nature Materials, 2011, 10(10): 765-771
[31] Sargent E H. Infrared photovoltaics made by solution processing. Nature Photonics, 2009, 3(6): 325-331
[32] Wang X, Koleilat G I, Tang J, Liu H, Kramer I J, Debnath R, Brzozowski L, Barkhouse D A R, Levina L, Hoogland S, Sargent E H. Tandem colloidal quantum dot solar cells employing a graded recombination layer. Nature Photonics, 2011, 5(8): 480-484
[33] Choi J J, Wenger W N, Hoffman R S, Lim Y F, Luria J, Jasieniak J, Marohn J A, Hanrath T. Solution-processed nanocrystal quantum dot tandem solar cells. Advanced Materials, 2011, 23(28): 3144-3148
[34] Koleilat G I,Wang X, Sargent E H. Graded recombination layers for multijunction photovoltaics. Nano Letters, 2012, 12(6): 3043-3049
[35] Tang J, Wang X, Brzozowski L, Barkhouse D A R, Debnath R, Levina L, Sargent E H. Schottky quantum dot solar cells stable in air under solar illumination. Advanced Materials, 2010, 22(12): 1398-1402
[36] Tang J, Brzozowski L, Barkhouse D A R, Wang X, Debnath R, Wolowiec R, Palmiano E, Levina L, Pattantyus-Abraham A G, Jamakosmanovic D, Sargent E H. Quantum dot photovoltaics in the extreme quantum confinement regime: the surface-chemical origins of exceptional air- and light-stability. ACS Nano, 2010, 4(2): 869-878
[37] Luther JM, Gao J, LloydMT, Semonin O E, BeardMC, Nozik A J. Stability assessment on a 3% bilayer PbS/ZnO quantum dot heterojunction solar cell. Advanced Materials, 2010, 22(33): 3704-3707
[38] Liu Y, Gibbs M, Perkins C L, Tolentino J, Zarghami M H, Bustamante J Jr., Law M. Robust, functional nanocrystal solids by infilling with atomic layer deposition. Nano Letters, 2011, 11(12): 5349-5355