Article
Chemistry, Physical
Debiprasad Panda, Manas Ranjan Mantri, Ravindra Kumar, Debabrata Das, Rajib Saha, Subhananda Chakrabarti
Summary: This study introduces an in-situ technique to tune the inter-dot coupling between vertically aligned InAs surface and buried quantum dots. The research finds that by reducing the monolayer coverage of the top quantum dot layer, the Fermi level pinning effect can be minimized and the energy level in the conduction band can be upshifted. The optimum 1.6 ML SQD structure achieves the highest level of Coulomb coupling and enhanced coupling between the two QD families. Additionally, using this structure reduces the dispersion in size and shape of the surface dots, further improving the efficiency of the sensor.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Inorganic & Nuclear
Mukesh K. Sahu, M. Jayasimhadri, D. Haranath
Summary: In this study, single phase crystalline Er3+ doped Ca3Bi(PO4)3 (CBP:Er3+) phosphors were prepared using chemical co-precipitation route. The structural, optical, morphological, and luminescent characteristics of the CBP:Er3+ phosphors were investigated, and their potential applications in optical thermometry and optoelectronic devices were explored.
SOLID STATE SCIENCES
(2022)
Article
Environmental Sciences
X. Venci, A. George, A. Dhayal Raj, A. Albert Irudayaraj, R. L. Josephine, S. John Sundaram, K. Kaviyarasu
Summary: The study synthesized CdSe nanoparticles using a hydrothermal process and characterized them, finding that CdSe nano-urchins synthesized at low concentrations are good photocatalysts.
ENVIRONMENTAL RESEARCH
(2022)
Article
Chemistry, Physical
Zifei Chen, J. Curtis Beimborn, Nicholas Kirkwood, Salvy P. Russo, J. Mathias Weber, Paul Mulvaney
Summary: The size-dependent pressure response of oleate-stabilized CdSe quantum dots in paraffin was investigated using diamond anvil cell experiments and density functional theory (DFT). The photoluminescence shows a blue-shift of around 43 meV/GPa for QDs above 3.0 nm, but the shift increases strongly for nanocrystals less than 3 nm in size. Conversely, the absorption shift is 45 meV/GPa above 3.0 nm but weakens to 35 meV/GPa for particles 1.5 nm in size. No crystallographic phase transitions occur below 2 GPa, and the optical effects are reversible. DFT calculations confirm that shifts in the bulk modulus begin for sizes estimated to be 1/2 of the Bohr radius, which we term the extreme confinement regime.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Analytical
Lei Hu, Weiren Zhao, Weijia Duan, Guojie Chen, Bingfeng Fan, Xiaoli Zhang
Summary: In this study, metal halide perovskite quantum dots with mixed cations of Formamidinium (FA) and Cs were fabricated using a solution-processed method at room temperature. By controlling the Cs doping ratios, the optical properties of these mixed-cation perovskite quantum dots were systematically investigated. The temperature-dependent photoluminescence spectra showed blue shifts as temperature increased, with widening full-width at half maximum, attributed to lattice thermal expansion and carrier-photon coupling effects. Excess Cs doping affected the optical properties at low temperatures due to the introduction of detrimental defects in the perovskite crystals. Controlling doping concentrations is crucial for the preparation of high-quality perovskite quantum dots and efficient optoelectronic devices.
Article
Materials Science, Multidisciplinary
Getu Sitotaw Tesfaye, Yen-Ting Li, Yu-Hao Wu, Tai-Sing Wu, Shih-Yu Fu, Chien-Yu Lee, Bo-Yi Chen, Gung-Chian Yin, Mau-Tsu Tang, Yu-Cheng Chiu, Bi-Hsuan Lin
Summary: This study investigates the carrier recombination mechanism of Cr-doped CsPbCl3 using temperature dependent photoluminescence and time-resolved photoluminescence. Exciton localization is observed due to non-uniform doping with Cr, and the excitons of Cr-doped CsPbCl3 exhibit a large localization depth. The results are anticipated to provide new avenues for characterizing the emission properties of inorganic lead trihalide perovskites.
Article
Nanoscience & Nanotechnology
Wanzhen Li, Ping Song, Ying Xin, Zhao Kuang, Qin Liu, Fei Ge, Longbao Zhu, Xuguang Zhang, Yugui Tao, Weiwei Zhang
Summary: The study demonstrated that loading AP on CdSe NPs resulted in higher water solubility, bioavailability, and antibacterial effect compared to raw AP. AP-CdSe NPs showed strong antibacterial activity against multidrug-resistant bacteria both in vitro and in vivo. The findings are helpful for the design and development of antibacterial treatment strategies based on AP.
INTERNATIONAL JOURNAL OF NANOMEDICINE
(2021)
Article
Materials Science, Multidisciplinary
Faiza Mustafa, Samia Aslam, Asim Arshad, Ashfaq Ahmad, Sadia Sagar, Sining Yun
Summary: This research presents the successful formation of ZnSe/amino functionalized graphene quantum dots (af-GQDs) with type-II core-shell structures. The structures show potential as a single emissive layer and exhibit tunable photoluminescence emission in the visible region. The introduction of functional groups on af-GQDs enhances their properties and reduces Auger recombination. The study also investigates the emission properties of ZnSe/af-GQDs through steady state and temperature dependent photoluminescence spectroscopy, as well as characterizes the structure using X-ray photon spectroscopy measurements. The findings suggest that ZnSe/af-GQDs have great potential for LEDs and display devices.
APPLIED MATERIALS TODAY
(2022)
Article
Chemistry, Physical
Wenke Li, Xiujian Zhao, Francois-Xavier Coudert, Chao Liu
Summary: In this study, the effects of calcium on the atomic and electronic structures of CdSe quantum dots (QDs) were investigated. It was found that the increase in CaO content in glass breaks the linkage between Na and O atoms, but interactions between Cd atoms and nonbridging oxygen atoms remain intact. CdSe QDs promote the migration of Na atoms to the interface and even the interior of QDs, while Ca atoms are only found at the QD/glass interface and in glass matrices far from the QDs. However, the influence of CdSe QDs on the glass structure is limited to a short range near the interface according to the radial concentration distribution. The increase in CaO content also results in an increase in the highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) gap of CdSe QD-embedded glasses. These findings contribute to a better understanding of the effects of calcium on the structural and luminescence properties of CdSe QD-embedded glasses.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Materials Science, Multidisciplinary
Sandeep Sharma, Sumandeep Kaur, A. S. Rao, Kamal Kishor
Summary: A set of Tb3+ and Tb3+/Sm3+ co-doped BaSrAlBSi glasses were produced and their optical properties were carefully examined. The glasses showed good transparency and thermal stability, and exhibited different emission characteristics including green, warm white, and orange light under different excitation wavelengths.
Article
Chemistry, Physical
Zunair Masroor, Usman Ali, Muhammad Aftab Akram, Muhammad Abdul Basit
Summary: The deposition of a SiO2 interfacial layer has been shown to enhance the deposition of CdS quantum dots and inhibit charge carrier recombination, leading to improved performance of QDSCs. This improvement was confirmed through various microscopy techniques and electrochemical investigations.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2022)
Article
Materials Science, Multidisciplinary
Getu Sitotaw Tesfaye, Yen-Ting Li, Yu-Hao Wu, Tai-Sing Wu, Chien-Yu Lee, Bo-Yi Chen, Gung-Chian Yin, Mau-Tsu Tang, Yu-Cheng Chiu, Bi-Hsuan Lin
Summary: This study investigates the recombination mechanisms of free and bound excitons in Eu-doped CsPbBr3. The emission intensity of free excitons decreases with decreasing temperature from 300 to 10 K, while the emission intensity of bound excitons appears at 100 K and rapidly increases with further temperature decrease. These phenomena are attributed to the dynamic migration of thermal energy between free and bound excitons caused by the presence of Eu3+ ions. The exciton-like emission is demonstrated by power-dependent photoluminescence (PL) experiments. Furthermore, the radiative and non-radiative recombinations of the bound exciton are determined through temperature-dependent time resolved photoluminescence (TR-PL), confirming that the bound exciton has an increased localization depth with decreasing temperature.
Article
Chemistry, Physical
Pascal Rusch, Denis Pluta, Franziska Luebkemann, Dirk Dorfs, Daniel Zambo, Nadja C. Bigall
Summary: Utilizing nanocrystals as building blocks for porous aerogel network structures preserves their unique nanoscopic properties while converting them into macroscopic solid structures. Understanding the interplay of network formation and its influence on properties is crucial for fabricating novel nanocrystal aerogels.
Article
Nanoscience & Nanotechnology
Yanbing Lv, Yucheng Yuan, Ning Hu, Na Jin, Dangdang Xu, Ruili Wu, Huaibin Shen, Ou Chen, Lin Song Li
Summary: This study presents a synthesis method for ultra-thick shell quantum dots and their application in C-reactive protein detection, achieving nearly a 3-fold enhancement in detection sensitivity and a 2-fold increase in shelf life. The performance improvements in protein detection are attributed to the use of core/shell quantum dots with high particle stability, high PL QYs, and a large surface area conducive to surface antibody coupling.
ACS APPLIED NANO MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Pengzhan Zhang, Leng Zhang, Fei Lyu, Danbei Wang, Ling Zhang, Kongpin Wu, Sake Wang, Chunmei Tang
Summary: Researchers have recently emphasized on the use of silicon-related materials for efficient light sources in Si-based optoelectronic integration. Previous studies mainly focused on Si nanostructured materials, and few exciting results have been obtained from Si-based compounds. This paper demonstrates the high photoluminescence external quantum efficiency (PL EQE) and internal quantum efficiency (PL IQE) of amorphous silicon oxynitride (a-SiNxOy) systems. The PL EQE values of a-SiNxOy measured within an integration sphere ranged from approximately 2% to 10% in the visible range at room temperature. The obtained PL IQE values were very high compared to reported Si-based luminescent thin films, reaching around 84% at 480 nm emission peak wavelength. The temperature-dependent PL EQE values of a-SiNxOy systems were also calculated and discussed.
Article
Nanoscience & Nanotechnology
Quyen T. Nguyen, Phuc D. Nguyen, Duc N. Nguyen, Quang Duc Truong, Tran Thi Kim Chi, Thuy Thi Dieu Ung, Itaru Honma, Nguyen Quang Liem, Phong D. Tran
ACS APPLIED MATERIALS & INTERFACES
(2018)
Article
Chemistry, Physical
Ung Thi Dieu Thuy, Irena Borisova, Olya Stoilova, Iliya Rashkov, Nguyen Quang Liem
Article
Chemistry, Multidisciplinary
Linh N. Nguyen, Ung Thi Dieu Thuy, Quang Duc Truong, Itaru Honma, Quang Liem Nguyen, Phong D. Tran
CHEMISTRY-AN ASIAN JOURNAL
(2018)
Article
Nanoscience & Nanotechnology
T. D. Nguyen, J. O. Kim, Y. H. Kim, E. T. Kim, Q. L. Nguyen, S. J. Lee
Article
Chemistry, Multidisciplinary
Tran Thi Thuong Huyen, Tran Thi Kim Chi, Nguyen Duc Dung, Hendrik Kosslick, Nguyen Quang Liem
Article
Materials Science, Multidisciplinary
Pham Nam Thang, Le Xuan Hung, Dao Nguyen Thuan, Nguyen Thu Loan, Guillaume Binard, Willy Daney de Marcillac, Agnes Maitre, Nguyen Quang Liem, Laurent Coolen, Pham Thu Nga
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2019)
Article
Chemistry, Physical
Chuc T. Nguyen, Tuan M. Duong, Mai Nguyen, Quyen T. Nguyen, Anh D. Nguyen, Ung Thi Dieu Thuy, Quang Duc Truong, Tung T. Nguyen, Quang Liem Nguyen, Phong D. Tran
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2019)
Article
Chemistry, Physical
Hoang V. Le, Ly T. Le, Phong D. Tran, Jong-San Chang, Ung Thi Dieu Thuy, Nguyen Quang Liem
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2019)
Article
Nanoscience & Nanotechnology
U. T. D. Thuy, N. T. Thuy, N. T. Tung, E. Janssens, N. Q. Liem
Article
Multidisciplinary Sciences
Son A. Hoang, Liem Q. Nguyen, Nhung H. Nguyen, Chi Q. Tran, Dong Nguyen, Quy N. Vu, Chi M. Phan
SCIENTIFIC REPORTS
(2019)
Article
Chemistry, Physical
Vu Duc Chinh, Nguyen Quang Liem, Han Saem Cho, Sae Chae Jeoung
CATALYSIS COMMUNICATIONS
(2020)
Article
Nanoscience & Nanotechnology
Tran Thi Thu Huong, Nguyen Thu Loan, Thi Dieu Thuy Ung, Nguyen Thanh Tung, HyukSu Han, Nguyen Quang Liem
Summary: This paper presents the systematic synthesis of AgInS2 nanocrystals with different sizes by controlling the reaction temperature. The synthesis process involves the synthesis of Ag2S nanocrystals followed by the exchange of Ag+ with In3+ to form AgInS2 nanocrystals. GaS is then shelled on the AgInS2 core to form core/shell structures. The synthesized AgInS2/GaS nanocrystals exhibit clear excitonic absorptions and strong, narrow excitonic luminescence.
Article
Materials Science, Multidisciplinary
Tran Thi Thu Huong, Nguyen Thu Loan, Le Van Long, Tran Dinh Phong, Thuy Ung Thi Dieu, Nguyen Quang Liem
Summary: This article presents the high yield solvothermal syntheses of AgInS2 (AIS) core nanocrystals (NCs) and AIS/ZnS core/shell NCs that emit stably strong luminescence peaking around 665 nm. Increasing the thickness of the ZnS shell enhances the stability and luminescence of AIS/ZnS core/shell NCs. Time-resolved PL spectra show a longer emission delay in AIS/ZnS core/shell NCs.
Article
Chemistry, Multidisciplinary
Thi Quynh Xuan Le, Linh Nhat Nguyen, Thanh Tung Nguyen, Eun Ha Choi, Quang Liem Nguyen, Nagendra Kumar Kaushik, Nguyen Thuan Dao
Summary: This study investigated the effects of plasma treatment on the germination and growth of mung bean seeds and determined the optimal treatment parameters. The results showed that plasma treatment significantly enhanced germination and growth, and the mechanism behind the treatment effects was revealed through observations and measurements of the seed coating.
APPLIED SCIENCES-BASEL
(2022)
Article
Nanoscience & Nanotechnology
Thuy Ung Thi Dieu, Liem Nguyen Quang
ADVANCES IN NATURAL SCIENCES-NANOSCIENCE AND NANOTECHNOLOGY
(2020)
