The photothermal stability of PbS quantum dot solids.

We combine optical absorption spectroscopy, ex situ transmission electron microscopy (TEM) imaging, and variable-temperature measurements to study the effect of ultraviolet (UV) light and heat treatments on ethanedithiol-treated PbS quantum dot (QD) films as a function of ambient atmosphere, temperature, and QD size. Film aging occurs mainly by oxidation or ripening and sintering depending on QD size and the presence of oxygen. We can stop QD oxidation and greatly suppress ripening by infilling the films with amorphous Al(2)O(3) using room-temperature atomic layer deposition (ALD).

[1]  G. Parsons,et al.  Atomic layer deposition and biocompatibility of titanium nitride nano-coatings on cellulose fiber substrates , 2009, Biomedical materials.

[2]  A. Nozik,et al.  Theoretical Studies of Electronic State Localization and Wormholes in Silicon Quantum Dot Arrays , 2001 .

[3]  E. Aydil,et al.  Solar cells based on junctions between colloidal PbSe nanocrystals and thin ZnO films. , 2009, ACS nano.

[4]  H. Lee,et al.  Bottom- and top-gate field-effect thin-film transistors with p channels of sintered HgTe nanocrystals , 2006 .

[5]  A Paul Alivisatos,et al.  Photovoltaic devices employing ternary PbSxSe1-x nanocrystals. , 2009, Nano letters.

[6]  P. Guyot-Sionnest,et al.  Atomic Layer Deposition of ZnO in Quantum Dot Thin Films , 2009 .

[7]  G. Konstantatos,et al.  Ultrasensitive solution-cast quantum dot photodetectors , 2006, Nature.

[8]  M. Artemyev,et al.  Electroluminescence in thin solid films of closely-packed CdS nanocrystals , 1998 .

[9]  Edward H. Sargent,et al.  Efficient, stable infrared photovoltaics based on solution-cast colloidal quantum dots. , 2008, ACS nano.

[10]  T. Riedl,et al.  Reliable thin film encapsulation for organic light emitting diodes grown by low-temperature atomic layer deposition , 2009 .

[11]  Barbara K. Hughes,et al.  Structural, optical, and electrical properties of PbSe nanocrystal solids treated thermally or with simple amines. , 2008, Journal of the American Chemical Society.

[12]  M. Kastner,et al.  Charge transport in PbSe nanocrystal arrays , 2008 .

[13]  J. Schoonman,et al.  Inorganic Nanocomposites of n‐ and p‐Type Semiconductors: A New Type of Three‐Dimensional Solar Cell , 2004 .

[14]  Mato Knez,et al.  Synthesis and Surface Engineering of Complex Nanostructures by Atomic Layer Deposition , 2007 .

[15]  William W. Yu,et al.  Ligand Effects on Synthesis and Post-Synthetic Stability of PbSe Nanocrystals , 2010 .

[16]  Eiji Ohtani,et al.  Electroluminescence from single monolayers of nanocrystals in molecular organic devices , 2022 .

[17]  A. Alivisatos,et al.  Light-emitting diodes made from cadmium selenide nanocrystals and a semiconducting polymer , 1994, Nature.

[18]  G. Pandraud,et al.  Low-temperature nanocrystal unification through rotations and relaxations probed by in situ transmission electron microscopy. , 2008, Nano letters.

[19]  Jiang Tang,et al.  Schottky Quantum Dot Solar Cells Stable in Air under Solar Illumination , 2010, Advanced materials.

[20]  J. H. Blokland,et al.  Tailoring the physical properties of thiol-capped PbS quantum dots by thermal annealing , 2009, Nanotechnology.

[21]  Ridley,et al.  All-Inorganic Field Effect Transistors Fabricated by Printing. , 1999, Science.

[22]  Byung-Ryool Hyun,et al.  PbSe nanocrystal excitonic solar cells. , 2009, Nano letters.

[23]  Mato Knez,et al.  Atomic layer deposition on biological macromolecules: metal oxide coating of tobacco mosaic virus and ferritin. , 2006, Nano letters.

[24]  Lukasz Brzozowski,et al.  Ambient-processed colloidal quantum dot solar cells via individual pre-encapsulation of nanoparticles. , 2010, Journal of the American Chemical Society.

[25]  Jianbo Gao,et al.  Quantum dot size dependent J-V characteristics in heterojunction ZnO/PbS quantum dot solar cells. , 2011, Nano letters.

[26]  Matt Law,et al.  Structural, optical, and electrical properties of self-assembled films of PbSe nanocrystals treated with 1,2-ethanedithiol. , 2008, ACS nano.

[27]  Vladimir Bulovic,et al.  Photodetectors based on treated CdSe quantum-dot films , 2005 .

[28]  Gregory D. Scholes,et al.  Colloidal PbS Nanocrystals with Size‐Tunable Near‐Infrared Emission: Observation of Post‐Synthesis Self‐Narrowing of the Particle Size Distribution , 2003 .

[29]  Steve Dunn,et al.  Fabrication and characterization of red-emitting electroluminescent devices based on thiol-stabilized semiconductor nanocrystals , 2007 .

[30]  M. Kastner,et al.  Temperature-, gate-, and photoinduced conductance of close-packed CdTe nanocrystal films , 2006 .

[31]  H. Möhwald,et al.  Electroluminescence of different colors from polycation/CdTe nanocrystal self-assembled films , 2000 .

[32]  Ratan Debnath,et al.  Depleted-heterojunction colloidal quantum dot solar cells. , 2010, ACS nano.

[33]  E. Aydil,et al.  Influence of Atmospheric Gases on the Electrical Properties of PbSe Quantum-Dot Films , 2010 .

[34]  Eminet Gebremichael,et al.  p-Type PbSe and PbS quantum dot solids prepared with short-chain acids and diacids. , 2010, ACS nano.

[35]  Jianbo Gao,et al.  n-Type transition metal oxide as a hole extraction layer in PbS quantum dot solar cells. , 2011, Nano letters.

[36]  K.-S. Cho,et al.  Three-dimensional binary superlattices of magnetic nanocrystals and semiconductor quantum dots , 2003, Nature.

[37]  A. Pattantyus-Abraham,et al.  Photostability of Colloidal PbSe and PbSe/PbS Core/Shell Nanocrystals in Solution and in the Solid State , 2007 .

[38]  Dmitri V Talapin,et al.  PbSe Nanocrystal Solids for n- and p-Channel Thin Film Field-Effect Transistors , 2005, Science.

[39]  Edward H. Sargent,et al.  Efficient solution-processed infrared photovoltaic cells: Planarized all-inorganic bulk heterojunction devices via inter-quantum-dot bridging during growth from solution , 2007 .

[40]  Alexey Y. Koposov,et al.  Effect of air exposure on surface properties, electronic structure, and carrier relaxation in PbSe nanocrystals. , 2010, ACS nano.

[41]  T. Vlugt,et al.  Morphological transformations and fusion of PbSe nanocrystals studied using atomistic simulations. , 2010, Nano letters.

[42]  Itaru Kamiya,et al.  Fabrication and coupling investigation of films of PbS quantum dots , 2010 .

[43]  V. Bulović,et al.  Colloidal PbS quantum dot solar cells with high fill factor. , 2010, ACS nano.

[44]  Philippe Guyot-Sionnest,et al.  n-Type Conducting CdSe Nanocrystal Solids , 2003, Science.

[45]  Matt Law,et al.  Schottky solar cells based on colloidal nanocrystal films. , 2008, Nano letters.

[46]  A. Nozik Quantum dot solar cells , 2002 .

[47]  Christopher B. Murray,et al.  Structural diversity in binary nanoparticle superlattices , 2006, Nature.

[48]  Matthew C. Beard,et al.  Determining the internal quantum efficiency of PbSe nanocrystal solar cells with the aid of an optical model. , 2008, Nano letters.

[49]  Ye Tao,et al.  Self-organized phase segregation between inorganic nanocrystals and PC61BM for hybrid high-efficiency bulk heterojunction photovoltaic cells , 2010 .

[50]  D. Ginger,et al.  Charge injection and transport in films of CdSe nanocrystals , 2000 .

[51]  D. A. Slater,et al.  Low-temperature, chemically driven atomic-layer epitaxy: In situ monitored growth of CdS/ZnSe(100) , 1997 .

[52]  P. Li,et al.  Low‐Temperature Atomic Layer‐Deposited TiO2 Films with Low Photoactivity , 2009 .

[53]  I. Moreels,et al.  Size-dependent optical properties of colloidal PbS quantum dots. , 2009, ACS nano.

[54]  M. Kastner,et al.  Photoconductivity Studies of Treated CdSe Quantum Dot Films Exhibiting Increased Exciton Ionization Efficiency , 2004 .

[55]  Dmitri V Talapin,et al.  Synergism in binary nanocrystal superlattices leads to enhanced p-type conductivity in self-assembled PbTe/Ag2 Te thin films. , 2007, Nature materials.

[56]  T. Rajh,et al.  Comparison of structural behavior of nanocrystals in randomly packed films and long-range ordered superlattices by time-resolved small angle X-ray scattering. , 2009, Journal of the American Chemical Society.

[57]  Klaus,et al.  Growth of SiO2 at room temperature with the use of catalyzed sequential half-reactions , 1997, Science.

[58]  S. George,et al.  Low-Temperature Al2O3 Atomic Layer Deposition , 2004 .

[59]  T. Krauss,et al.  Photobrightening and photodarkening in PbS quantum dots. , 2006, Physical chemistry chemical physics : PCCP.

[60]  Lukasz Brzozowski,et al.  Quantum dot photovoltaics in the extreme quantum confinement regime: the surface-chemical origins of exceptional air- and light-stability. , 2010, ACS nano.

[61]  Electronic transport in films of colloidal CdSe nanocrystals , 2002, cond-mat/0204560.

[62]  Jianbo Gao,et al.  Stability Assessment on a 3% Bilayer PbS/ZnO Quantum Dot Heterojunction Solar Cell , 2010, Advanced materials.

[63]  William W. Yu,et al.  Stability study of PbSe semiconductor nanocrystals over concentration, size, atmosphere, and light exposure. , 2009, Langmuir : the ACS journal of surfaces and colloids.

[64]  Dmitri V Talapin,et al.  Structural characterization of self-assembled multifunctional binary nanoparticle superlattices. , 2006, Journal of the American Chemical Society.