Development of Cu-In-Ga-S quantum dots with a narrow emission peak for red electroluminescence.

Narrowing the emission peak width and adjusting the peak position play a key role in the chromaticity and color accuracy of display devices with the use of quantum dot light-emitting diodes (QD-LEDs). In this study, we developed multinary Cu-In-Ga-S (CIGS) QDs showing a narrow photoluminescence (PL) peak by controlling the Cu fraction, i.e., Cu/(In+Ga), and the ratio of In to Ga composing the QDs. The energy gap of CIGS QDs was enlarged from 1.74 to 2.77 eV with a decrease in the In/(In+Ga) ratio from 1.0 to 0. The PL intensity was remarkably dependent on the Cu fraction, and the PL peak width was dependent on the In/(In+Ga) ratio. The sharpest PL peak at 668 nm with a full width at half maximum (fwhm) of 0.23 eV was obtained for CIGS QDs prepared with ratios of Cu/(In+Ga) = 0.3 and In/(In+Ga) = 0.7, being much narrower than those previously reported with CIGS QDs, fwhm of >0.4 eV. The PL quantum yield of CIGS QDs, 8.3%, was increased to 27% and 46% without a PL peak broadening by surface coating with GaSx and Ga-Zn-S shells, respectively. Considering a large Stokes shift of >0.5 eV and the predominant PL decay component of ∼200-400 ns, the narrow PL peak was assignable to the emission from intragap states. QD-LEDs fabricated with CIGS QDs surface-coated with GaSx shells showed a red color with a narrow emission peak at 688 nm with a fwhm of 0.24 eV.

[1]  S. Kuwabata,et al.  Quantum-Dot Light-Emitting Diodes Exhibiting Narrow-Spectrum Green Electroluminescence by Using Ag-In-Ga-S/GaSx Quantum Dots. , 2023, ACS applied materials & interfaces.

[2]  S. Kuwabata,et al.  Controlling Optical Properties and Electronic Energy Structure of I-III-VI Semiconductor Quantum Dots for Improving Their Photofunctions , 2022, Journal of Photochemistry and Photobiology C: Photochemistry Reviews.

[3]  Y. Iwasaki,et al.  Pure-colored red, green, and blue quantum dot light-emitting diodes using emitting layers composed of cadmium-free quantum dots and organic electron-transporting materials , 2022, Japanese Journal of Applied Physics.

[4]  Y. Baba,et al.  Photoluminescence properties of quinary Ag–(In,Ga)–(S,Se) quantum dots with a gradient alloy structure for in vivo bioimaging , 2021, Journal of Materials Chemistry C.

[5]  S. Kuwabata,et al.  Luminescent Quaternary Ag(InxGa1-x)S2/GaSy Core/Shell Quantum Dots Prepared Using Dithiocarbamate Compounds and Photoluminescence Recovery via Post Treatment. , 2021, Inorganic chemistry.

[6]  P. K. Mandal,et al.  Near-Unity Photoluminescence Quantum Yield and Highly Suppressed Blinking in a Toxic-Metal-Free Quantum Dot. , 2021, The journal of physical chemistry letters.

[7]  S. Kuwabata,et al.  Electroluminescence from band-edge-emitting AgInS2/GaSx core/shell quantum dots , 2020 .

[8]  Takahisa Yamamoto,et al.  Controlling the visible-light driven photocatalytic activity of alloyed ZnSe–AgInSe2 quantum dots for hydrogen production , 2020 .

[9]  Y. Baba,et al.  Tailored Photoluminescence Properties of Ag(In,Ga)Se2 Quantum Dots for Near-Infrared In Vivo Imaging , 2020 .

[10]  Han-zhuang Zhang,et al.  Exploring Electronic and Excitonic Processes Towards Efficient Deep Red CuInS2/ZnS Quantum-dot Light-emitting Diodes. , 2019, ACS applied materials & interfaces.

[11]  T. Wada,et al.  Control of electronic structure in Cu(In, Ga)(S, Se)2 for high-efficiency solar cells , 2019, Japanese Journal of Applied Physics.

[12]  X. W. Sun,et al.  Recent advances in quantum dot-based light-emitting devices: Challenges and possible solutions , 2019, Materials Today.

[13]  Hao Zhang,et al.  Facile Synthesis of Cu–In–S/ZnS Core/Shell Quantum Dots in 1-Dodecanethiol for Efficient Light-Emitting Diodes with an External Quantum Efficiency of 7.8% , 2018, Chemistry of Materials.

[14]  S. Kuwabata,et al.  Wavelength-Tunable Band-Edge Photoluminescence of Nonstoichiometric Ag-In-S Nanoparticles via Ga3+ Doping. , 2018, ACS applied materials & interfaces.

[15]  J. J. Geuchies,et al.  Tuning and Probing the Distribution of Cu+ and Cu2+ Trap States Responsible for Broad-Band Photoluminescence in CuInS2 Nanocrystals , 2018, ACS nano.

[16]  Jinjie Li,et al.  Synthesis of highly stable CuInZnS/ZnS//ZnS quantum dots with thick shell and its application to quantitative immunoassay , 2018, Chemical Engineering Journal.

[17]  S. Kuwabata,et al.  Narrow band-edge photoluminescence from AgInS2 semiconductor nanoparticles by the formation of amorphous III–VI semiconductor shells , 2018, NPG Asia Materials.

[18]  V. Wood,et al.  Tuning the Composition of Multicomponent Semiconductor Nanocrystals: The Case of I–III–VI Materials , 2018 .

[19]  N. Makarov,et al.  Light Emission Mechanisms in CuInS2 Quantum Dots Evaluated by Spectral Electrochemistry , 2017 .

[20]  D. Zahn,et al.  A Fine Size Selection of Brightly Luminescent Water-Soluble Ag–In–S and Ag–In–S/ZnS Quantum Dots , 2017 .

[21]  N. Makarov,et al.  Thick-Shell CuInS2/ZnS Quantum Dots with Suppressed "Blinking" and Narrow Single-Particle Emission Line Widths. , 2017, Nano letters.

[22]  Heesun Yang,et al.  High-Efficiency Cu–In–S Quantum-Dot-Light-Emitting Device Exceeding 7% , 2016 .

[23]  Gang Xu,et al.  High luminance of CuInS2-based yellow quantum dot light emitting diodes fabricated by all-solution processing , 2016 .

[24]  Heesun Yang,et al.  White Electroluminescent Lighting Device Based on a Single Quantum Dot Emitter , 2016, Advanced materials.

[25]  Koki Inoue,et al.  Light-stimulated carrier dynamics of CuInS2/CdS heterotetrapod nanocrystals. , 2016, Nanoscale.

[26]  A. Nassiopoulou,et al.  Steady state and time resolved photoluminescence properties of CuInS2/ZnS quantum dots in solutions and in solid films , 2015 .

[27]  Tatsuya Kameyama,et al.  Controlling the Electronic Energy Structure of ZnS–AgInS2 Solid Solution Nanocrystals for Photoluminescence and Photocatalytic Hydrogen Evolution , 2015 .

[28]  D. Gamelin,et al.  Singlet-Triplet Splittings in the Luminescent Excited States of Colloidal Cu(+):CdSe, Cu(+):InP, and CuInS2 Nanocrystals: Charge-Transfer Configurations and Self-Trapped Excitons. , 2015, Journal of the American Chemical Society.

[29]  Gang Xu,et al.  A high efficient photoluminescence Zn–Cu–In–S/ZnS quantum dots with long lifetime , 2015 .

[30]  Sang Hyun Park,et al.  Highly bright yellow-green-emitting CuInS₂ colloidal quantum dots with core/shell/shell architecture for white light-emitting diodes. , 2015, ACS applied materials & interfaces.

[31]  S. Chang,et al.  Synthesis of CuInS2 quantum dots using polyetheramine as solvent , 2015, Nanoscale Research Letters.

[32]  Masayuki Kanehara,et al.  Origin of surface trap states in CdS quantum dots: relationship between size dependent photoluminescence and sulfur vacancy trap states. , 2015, Physical chemistry chemical physics : PCCP.

[33]  Sanjaya D. Perera,et al.  Nanocluster seed-mediated synthesis of CuInS2 quantum dots, nanodisks, nanorods, and doped Zn-CuInGaS2 quantum dots , 2015 .

[34]  J. Hwang,et al.  Cu−In−Ga−S quantum dot composition-dependent device performance of electrically driven light-emitting diodes , 2014 .

[35]  Jun‐Jie Zhu,et al.  Near-Infrared Emitting AgInS2/ZnS Nanocrystals , 2014 .

[36]  Heesun Yang,et al.  White lighting device from composite films embedded with hydrophilic Cu(In, Ga)S2/ZnS and hydrophobic InP/ZnS quantum dots , 2014, Nanotechnology.

[37]  Heesun Yang,et al.  Synthesis of color-tunable Cu–In–Ga–S solid solution quantum dots with high quantum yields for application to white light-emitting diodes , 2012 .

[38]  S. Achilefu,et al.  High-Quality CuInS2/ZnS Quantum Dots for In vitro and In vivo Bioimaging , 2012 .

[39]  Zhan'ao Tan,et al.  Highly Emissive and Color‐Tunable CuInS2‐Based Colloidal Semiconductor Nanocrystals: Off‐Stoichiometry Effects and Improved Electroluminescence Performance , 2012 .

[40]  Y. Hamanaka,et al.  Photoluminescence Properties and Its Origin of AgInS2 Quantum Dots with Chalcopyrite Structure , 2011 .

[41]  V. Klimov,et al.  Efficient synthesis of highly luminescent copper indium sulfide-based core/shell nanocrystals with surprisingly long-lived emission. , 2011, Journal of the American Chemical Society.

[42]  J. Luther,et al.  Absolute Photoluminescence Quantum Yields of IR-26 Dye, PbS, and PbSe Quantum Dots , 2010 .

[43]  V. Bulović,et al.  Colloidal quantum dot light-emitting devices , 2010, Nano reviews.

[44]  Liang Li,et al.  Core/Shell semiconductor nanocrystals. , 2009, Small.

[45]  Miroslaw Batentschuk,et al.  Silica‐Coated InP/ZnS Nanocrystals as Converter Material in White LEDs , 2008 .

[46]  Prashant V. Kamat,et al.  Quantum Dot Solar Cells. Semiconductor Nanocrystals as Light Harvesters , 2008 .

[47]  F. V. Veggel,et al.  Highly Photoluminescent PbS Nanocrystals: The Beneficial Effect of Trioctylphosphine , 2008 .

[48]  Huifeng Qian,et al.  Study of fluorescence quenching and dialysis process of CdTe quantum dots, using ensemble techniques and fluorescence correlation spectroscopy. , 2006, The journal of physical chemistry. B.

[49]  Hiroshi Yokoyama,et al.  Temperature-sensitive photoluminescence of CdSe quantum dot clusters. , 2005, The journal of physical chemistry. B.

[50]  V. Gremenok,et al.  Free and bound exciton emission in CuInSe2 and CuGaSe2 single crystals , 1998 .

[51]  Xiaogang Peng,et al.  Epitaxial Growth of Highly Luminescent CdSe/CdS Core/Shell Nanocrystals with Photostability and Electronic Accessibility , 1997 .

[52]  Taro Uematsu,et al.  [Paper] Green Electroluminescence Generated by Band-edge Transition in Ag-In-Ga-S/GaSx Core/shell Quantum Dots , 2021, ITE Transactions on Media Technology and Applications.

[53]  K. Chung,et al.  The photoluminescence of CuInS2 nanocrystals: effect of non-stoichiometry and surface modification , 2012 .