Bandgap Tuning by Using a Lattice Distortion Induced by Two Symmetries That Coexist in a Quantum Dot

Kong, Eui-Hyun; Chang, Yong‐June; Park, Hyunjin; Jang, Hyun M.

doi:10.1002/smll.201303040

Cited by 11 publications

(4 citation statements)

References 42 publications

(56 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Ag phases in a quantum dot. 52 ZnS had a strong absorbance only in UV region with the calculated optical bandgap of 3.68 eV, which was consistent with previous works of Borah et al 53 and U ̈zar et al 54 After forming solid solution, the visible light absorbance of (AgIn) x Zn 2(1−x) S 2 increased, and its absorbance edge was shifted to a lower bandgap value. The calculated bandgap of (AgIn) x Zn 2(1−x) S 2 was about 2.81 eV, as shown in Figure 6, panel b.…”

Section: Resultssupporting

confidence: 91%

“…Figure , panel a shows that Ag 2 S nanoparticles had a strong visible light absorbance with the calculated optical bandgap of 1.92 eV. The bandgap of Ag 2 S could be tailored between 1.64 and 2.51 eV due to the lattice distortion caused by coexisting of monoclinic Ag 2 S and cubic Ag phases in a quantum dot . ZnS had a strong absorbance only in UV region with the calculated optical bandgap of 3.68 eV, which was consistent with previous works of Borah et al and Üzar et al After forming solid solution, the visible light absorbance of (AgIn) x Zn 2(1– x ) S 2 increased, and its absorbance edge was shifted to a lower bandgap value.…”

Section: Resultssupporting

confidence: 88%

See 1 more Smart Citation

Facile Synthesis of n-type (AgIn)_xZn_2(1–x)S₂/p-type Ag₂S Nanocomposite for Visible Light Photocatalytic Reduction To Detoxify Hexavalent Chromium

Abdullah

Kuo

2015

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

n-type (AgIn)(x)Zn(2(1-x))S2/p-type Ag2S nanocomposites with 10%, 20%, and 30% Ag2S loading were successfully synthesized via the simple solvothermal and sol gel methods. The as-prepared nanocomposites were characterized, and their visible light photocatalytic reductions were tested for detoxification of hexavalent chromium (Cr(VI)). The results showed only 20 mg of the as-prepared nanocomposites could reduce 100 mL of 20 ppm potassium dichromate by almost 100% in less than 90 min without adding any hole scavenger agents and pH adjustment (pH = 7). The good photocatalytic reduction was related to the narrower bandgap of (AgIn)(x)Zn(2(1-x))S2 solid solution because of the hybridized orbitals of Ag, In, Zn, and S and low recombination rate of photogenerated electron and hole pairs due to the effectiveness of p-type Ag2S and n-type (AgIn)(x)Zn(2(1-x))S2 nanoheterojunctions. This work not only gives a contribution to the creation of visible light photocatalysis for wide-bandgap semiconductors, but also extends our technological viewpoints in designing highly efficient metal sulfide photocatalyst. To the best of our knowledge, this work is the first finding of a high photocatalytic reduction of hexavalent chromium under visible light illumination by simultaneously using both concepts of p-n nanoheterojunction and solid solution in our photocatalyst design. In this present work, these concepts were used to replace the use of hole scavenger agents, which were commonly used by many other works to retard the recombination rate of photoinduced electron and hole pairs for photodegradation of hexavalent chromium.

show abstract

Section: Resultssupporting

confidence: 91%

Section: Resultssupporting

confidence: 88%

Facile Synthesis of n-type (AgIn)_xZn_2(1–x)S₂/p-type Ag₂S Nanocomposite for Visible Light Photocatalytic Reduction To Detoxify Hexavalent Chromium

Abdullah

Kuo

2015

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

show abstract

“…Semiconductor core/shell quantum dots (QDs) receive strong attention due to the tunability of their electronic properties, leading to many relevant nanotechnology and optoelectronic applications [1][2][3][4][5][6][7]. Both germanium and silicon are materials frequently used in the electronic industry; in addition, they show strong confinement effects in QDs [7,8].…”

Section: Introductionmentioning

confidence: 99%

Ge/Si core/shell quantum dots in alumina: tuning the optical absorption by the core and shell size

et al. 2017

View full text Add to dashboard Cite

Ge/Si core/shell quantum dots (QDs) recently received extensive attention due to their specific properties induced by the confinement effects of the core and shell structure. They have a type II confinement resulting in spatially separated charge carriers, the electronic structure strongly dependent on the core and shell size. Herein, the experimental realization of Ge/Si core/shell QDs with strongly tunable optical properties is demonstrated. QDs embedded in an amorphous alumina glass matrix are produced by simple magnetron sputtering deposition. In addition, they are regularly arranged within the matrix due to their self-assembled growth regime. QDs with different Ge core and Si shell sizes are made. These core/shell structures have a significantly stronger absorption compared to pure Ge QDs and a highly tunable absorption peak dependent on the size of the core and shell. The optical properties are in agreement with recent theoretical predictions showing the dramatic influence of the shell size on optical gap, resulting in 0.7 eV blue shift for only 0.4 nm decrease at the shell thickness. Therefore, these materials are very promising for light-harvesting applications.

show abstract

“…Highly sensitive in vivo imaging of xenograft tumor on a mouse model was realized by injecting Ag 2 S QDs via the tail vein because of the enhanced permeability and retention (EPR) effect of tumor vasculature . Furthermore, negligible toxicity promises the potential clinical applications of Ag 2 S QDs. − In addition to their biomedical applications, Ag 2 S QDs present enormous potential for applications in solar cell and electronic transport. − …”

Section: Introductionmentioning

confidence: 99%

Controlled Synthesis of Ag₂S Quantum Dots and Experimental Determination of the Exciton Bohr Radius

et al. 2014

View full text Add to dashboard Cite

Ag 2 S quantum dots (QDs) have attracted increasing attention due to their appealing optical properties in the near-infrared regime. However, a full understanding of the quantum confinement effect of Ag 2 S QDs has not been achieved so far. Herein, for the first time, the size-dependent excited state optical properties of Ag 2 S QDs are systematically investigated by photoluminescence (PL), PL excitation (PLE), and time-resolved PL spectroscopy. Experimentally, we determine the exciton Bohr radius of Ag 2 S QDs as 2.2 nm, which is highly consistent with theoretical results.

show abstract

Bandgap Tuning by Using a Lattice Distortion Induced by Two Symmetries That Coexist in a Quantum Dot

Cited by 11 publications

References 42 publications

Facile Synthesis of n-type (AgIn)_xZn_2(1–x)S₂/p-type Ag₂S Nanocomposite for Visible Light Photocatalytic Reduction To Detoxify Hexavalent Chromium

Facile Synthesis of n-type (AgIn)_xZn_2(1–x)S₂/p-type Ag₂S Nanocomposite for Visible Light Photocatalytic Reduction To Detoxify Hexavalent Chromium

Ge/Si core/shell quantum dots in alumina: tuning the optical absorption by the core and shell size

Controlled Synthesis of Ag₂S Quantum Dots and Experimental Determination of the Exciton Bohr Radius

Contact Info

Product

Resources

About

Bandgap Tuning by Using a Lattice Distortion Induced by Two Symmetries That Coexist in a Quantum Dot

Cited by 11 publications

References 42 publications

Facile Synthesis of n-type (AgIn)xZn2(1–x)S2/p-type Ag2S Nanocomposite for Visible Light Photocatalytic Reduction To Detoxify Hexavalent Chromium

Facile Synthesis of n-type (AgIn)xZn2(1–x)S2/p-type Ag2S Nanocomposite for Visible Light Photocatalytic Reduction To Detoxify Hexavalent Chromium

Ge/Si core/shell quantum dots in alumina: tuning the optical absorption by the core and shell size

Controlled Synthesis of Ag2S Quantum Dots and Experimental Determination of the Exciton Bohr Radius

Contact Info

Product

Resources

About

Facile Synthesis of n-type (AgIn)_xZn_2(1–x)S₂/p-type Ag₂S Nanocomposite for Visible Light Photocatalytic Reduction To Detoxify Hexavalent Chromium

Facile Synthesis of n-type (AgIn)_xZn_2(1–x)S₂/p-type Ag₂S Nanocomposite for Visible Light Photocatalytic Reduction To Detoxify Hexavalent Chromium

Controlled Synthesis of Ag₂S Quantum Dots and Experimental Determination of the Exciton Bohr Radius