1
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Qin M, Khan IM, Ding N, Qi S, Dong X, Zhang Y, Wang Z. Aptamer-modified paper-based analytical devices for the detection of food hazards: Emerging applications and future perspective. Biotechnol Adv 2024; 73:108368. [PMID: 38692442 DOI: 10.1016/j.biotechadv.2024.108368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 03/10/2024] [Accepted: 04/24/2024] [Indexed: 05/03/2024]
Abstract
Food analysis plays a critical role in assessing human health risks and monitoring food quality and safety. Currently, there is a pressing need for a reliable, portable, and quick recognition element for point-of-care testing (POCT) to better serve the demands of on-site food analysis. Aptamer-modified paper-based analytical devices (Apt-PADs) have excellent characteristics of high portability, high sensitivity, high specificity, and on-site detection, which have been widely used and concerned in the field of food safety. The article reviews the basic components and working principles of Apt-PADs, and introduces their representative applications detecting food hazards. Finally, the advantages, challenges, and future directions of Apt-PADs-based sensing performance are discussed, to provide new directions and insights for researchers to select appropriate Apt-PADs according to specific applications.
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Affiliation(s)
- Mingwei Qin
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Imran Mahmood Khan
- Nottingham Ningbo China Beacons of Excellence Research and Innovation Institute, University of Nottingham Ningbo China, Ningbo 315100, PR China
| | - Ning Ding
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Shuo Qi
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Xiaoze Dong
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Yin Zhang
- Key Laboratory of Meat Processing of Sichuan, Chengdu University, Chengdu 610106, China
| | - Zhouping Wang
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; Key Laboratory of Meat Processing of Sichuan, Chengdu University, Chengdu 610106, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, China; National Engineering Research Center for Functional Food, Jiangnan University, Wuxi 214122, China.
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2
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Yuan C, He M, Liao X, Liu M, Zhang Q, Wan Q, Qu Z, Kong L, Li L. Interface defects repair of core/shell quantum dots through halide ion penetration. Chem Sci 2023; 14:13119-13125. [PMID: 38023521 PMCID: PMC10664535 DOI: 10.1039/d3sc04136k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 10/31/2023] [Indexed: 12/01/2023] Open
Abstract
The interface defects of core-shell colloidal quantum dots (QDs) affect their optoelectronic properties and charge transport characteristics. However, the limited available strategies pose challenges in the comprehensive control of these interface defects. Herein, we introduce a versatile strategy that effectively addresses both surface and interface defects in QDs through simple post-synthesis treatment. Through the combination of fine chemical etching methods and spectroscopic analysis, we have revealed that halogens can diffuse within the crystal structure at elevated temperatures, acting as "repairmen" to rectify oxidation and significantly reducing interface defects within the QDs. Under the guidance of this protocol, InP core/shell QDs were synthesized by a hydrofluoric acid-free method with a full width at half-maximum of 37.0 nm and an absolute quantum yield of 86%. To further underscore the generality of this strategy, we successfully applied it to CdSe core/shell QDs as well. These findings provide fundamental insights into interface defect engineering and contribute to the advancement of innovative solutions for semiconductor nanomaterials.
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Affiliation(s)
- Changwei Yuan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 P. R. China
| | - Mengda He
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 P. R. China
| | - Xinrong Liao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 P. R. China
| | - Mingming Liu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 P. R. China
| | - Qinggang Zhang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 P. R. China
| | - Qun Wan
- Macao Institute of Materials Science and Engineering (MIMSE), Macau University of Science and Technology Taipa Macao 999078 P. R. China
| | - Zan Qu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 P. R. China
| | - Long Kong
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 P. R. China
| | - Liang Li
- Macao Institute of Materials Science and Engineering (MIMSE), Macau University of Science and Technology Taipa Macao 999078 P. R. China
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3
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Stam M, du Fossé I, Infante I, Houtepen AJ. Guilty as Charged: The Role of Undercoordinated Indium in Electron-Charged Indium Phosphide Quantum Dots. ACS NANO 2023; 17:18576-18583. [PMID: 37712414 PMCID: PMC10540256 DOI: 10.1021/acsnano.3c07029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 09/12/2023] [Indexed: 09/16/2023]
Abstract
Quantum dots (QDs) are known for their size-dependent optical properties, narrow emission bands, and high photoluminescence quantum yield (PLQY), which make them interesting candidates for optoelectronic applications. In particular, InP QDs are receiving a lot of attention since they are less toxic than other QD materials and are hence suitable for consumer applications. Most of these applications, such as LEDs, photovoltaics, and lasing, involve charging QDs with electrons and/or holes. However, charging of QDs is not easy nor innocent, and the effect of charging on the composition and properties of InP QDs is not yet well understood. This work provides theoretical insight into electron charging of the InP core and InP/ZnSe QDs. Density functional theory calculations are used to show that charging of InP-based QDs with electrons leads to the formation of trap states if the QD contains In atoms that are undercoordinated and thus have less than four bonds to neighboring atoms. InP core-only QDs have such atoms at the surface, which are responsible for the formation of trap states upon charging with electrons. We show that InP/ZnSe core-shell models with all In atoms fully coordinated can be charged with electrons without the formation of trap states. These results show that undercoordinated In atoms should be avoided at all times for QDs to be stably charged with electrons.
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Affiliation(s)
- Maarten Stam
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The
Netherlands
| | - Indy du Fossé
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The
Netherlands
| | - Ivan Infante
- BC
Materials, Basque Center for Materials, Applications, and Nanostructures, UPV/EHU Science Park, Leioa 48940, Spain
- Ikerbasque,
Basque Foundation for Science, Bilbao 48009, Spain
| | - Arjan J. Houtepen
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The
Netherlands
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4
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Huang B, Huang Y, Zhang H, Lu X, Gao X, Zhuang S. Electrochemical Control over the Optical Properties of II-VI Colloidal Nanoplatelets by Tailoring the Station of Extra Charge Carriers. ACS APPLIED MATERIALS & INTERFACES 2023; 15:21354-21363. [PMID: 37071128 DOI: 10.1021/acsami.2c21071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
An electrochemical (EC) method has been successfully applied to regulate the optical properties of nanocrystals, such as reducing their gain threshold by EC doping and enhancing their photoluminescence intensity by EC filling of trap states. However, the processes of EC doping and filling are rarely reported simultaneously in a single study, hindering the understanding of their underlying interactions. Here, we report the spectroelectrochemical (SEC) studies of quasi-two-dimensional nanoplatelets (NPLs), intending to clarify the above issues. EC doping is successfully achieved in CdSe/CdZnS core/shell NPLs, with red-shifted photoluminescence and a reversal of the emission intensity trend. The injection of extra electrons (holes) into the conduction (valence) band edges needs high bias voltages, while the passivation/activation process of trap states with the shift of Fermi level starts at lower EC potentials. Then, we explore the role of excitation light conditions in these processes, different from existing SEC research studies. Interestingly, increasing the laser power density can hinder EC electron injection, whereas decreasing the excitation energy evades the passivation process of trap states. Moreover, we demonstrate that EC control strategies can be used to realize color display and anti-counterfeiting applications via simultaneously tailoring the photoluminescence intensity of red- and green-emitting NPLs.
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Affiliation(s)
- Bo Huang
- Institute of Carbon Neutrality and New Energy, School of Electronics and Information, Hangzhou Dianzi University, Hangzhou, Zhejiang 310018, P.R. China
| | - Yihuai Huang
- Institute of Carbon Neutrality and New Energy, School of Electronics and Information, Hangzhou Dianzi University, Hangzhou, Zhejiang 310018, P.R. China
| | - Huichao Zhang
- Institute of Carbon Neutrality and New Energy, School of Electronics and Information, Hangzhou Dianzi University, Hangzhou, Zhejiang 310018, P.R. China
| | - Xinmiao Lu
- Institute of Carbon Neutrality and New Energy, School of Electronics and Information, Hangzhou Dianzi University, Hangzhou, Zhejiang 310018, P.R. China
| | - Xiumin Gao
- School of Optical Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
| | - Songlin Zhuang
- School of Optical Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
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5
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Yao J, Jin Z, Zhao Y. Electroactive and SERS-Active Ag@Cu 2O NP-Programed Aptasensor for Dual-Mode Detection of Tetrodotoxin. ACS APPLIED MATERIALS & INTERFACES 2023; 15:10240-10249. [PMID: 36749896 DOI: 10.1021/acsami.2c21424] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Dual-mode nanotags with noninterference sensing signals improved the detection accuracy and sensitivity for the applications of tetrodotoxin (TTX) monitoring. Electroactive and surface-enhanced Raman scattering (SERS)-active Ag@Cu2O nanoparticles (NPs) were fabricated and displayed two electrooxidation signals at -0.13 and 0.17 V, attributed to the oxidization process of Cu+ and Ag0, respectively. Ag@Cu2O NPs were also found to exhibit stronger SERS performances than individual Ag NPs. The dielectric Cu2O shell with a large dielectric constant inhibited the attenuation of electromagnetic (EM) waves of Ag NPs, which strengthened the EM fields for SERS enhancement. The electron transfer from Ag to Cu2O to 4-aminothiophenol (4-ATP) also contributed to the SERS performances. Ag@Cu2O NPs were modified by TTX aptamers and assembled with MXene nanosheets (NSs) due to the large surface, good conductivity, and inherent Raman properties. The assemblies showed two-peaked electrooxidation signals and prominent SERS activity. An electrochemical detection curve was established by using the total peak intensity at -0.13 and 0.17 V as detection signals, and a ratiometric SERS detection curve was developed by applying the intensity at 1078 cm-1 (4-ATP) as the detection signal and 730 cm-1 (MXene NSs) as the reference signal. An electrochemical and SERS signal-programed dual-mode aptasensor was proposed for accurate TTX detection, with the limits of detection of 31.6 pg/mL for the electrochemical signal and 38.3 pg/mL for the SERS signal. The rational design of plasmonic metal-semiconductor heterogeneous nanocomposites had important prospects in establishing a multimodal biosensing platform for the quantitative and accurate detection of analytes in complex systems.
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Affiliation(s)
- Jie Yao
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, International Joint Research Center for Photoresponsive Molecules and Materials, School of Chemical and Material Engineering, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Zhao Jin
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, International Joint Research Center for Photoresponsive Molecules and Materials, School of Chemical and Material Engineering, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Yuan Zhao
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, International Joint Research Center for Photoresponsive Molecules and Materials, School of Chemical and Material Engineering, Jiangnan University, Wuxi, Jiangsu 214122, China
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6
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Geuchies JJ, Dijkhuizen R, Koel M, Grimaldi G, du Fossé I, Evers WH, Hens Z, Houtepen AJ. Zero-Threshold Optical Gain in Electrochemically Doped Nanoplatelets and the Physics Behind It. ACS NANO 2022; 16:18777-18788. [PMID: 36256901 PMCID: PMC9706803 DOI: 10.1021/acsnano.2c07519] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 10/13/2022] [Indexed: 06/07/2023]
Abstract
Colloidal nanoplatelets (NPLs) are promising materials for lasing applications. The properties are usually discussed in the framework of 2D materials, where strong excitonic effects dominate the optical properties near the band edge. At the same time, NPLs have finite lateral dimensions such that NPLs are not true extended 2D structures. Here we study the photophysics and gain properties of CdSe/CdS/ZnS core-shell-shell NPLs upon electrochemical n doping and optical excitation. Steady-state absorption and PL spectroscopy show that excitonic effects are weaker in core-shell-shell nanoplatelets due to the decreased exciton binding energy. Transient absorption studies reveal a gain threshold of only one excitation per nanoplatelet. Using electrochemical n doping, we observe the complete bleaching of the band edge exciton transitions. Combining electrochemical doping with transient absorption spectroscopy, we demonstrate that the gain threshold is fully removed over a broad spectral range and gain coefficients of several thousand cm-1 are obtained. These doped NPLs are the best performing colloidal nanomaterial gain medium reported to date, with the lowest gain threshold and broadest gain spectrum and gain coefficients that are 4 times higher than in n-doped colloidal quantum dots. The low exciton binding energy due to the CdS and ZnS shells, in combination with the relatively small lateral size of the NPLs, results in excited states that are effectively delocalized over the entire platelet. Core-shell NPLs are thus on the border between strong confinement in QDs and dominant Coulombic effects in 2D materials. We demonstrate that this limit is in effect ideal for optical gain and that it results in an optimal lateral size of the platelets where the gain threshold per nm2 is minimal.
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Affiliation(s)
- Jaco J. Geuchies
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2926 HZDelft, The Netherlands
| | - Robbert Dijkhuizen
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2926 HZDelft, The Netherlands
| | - Marijn Koel
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2926 HZDelft, The Netherlands
| | - Gianluca Grimaldi
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2926 HZDelft, The Netherlands
| | - Indy du Fossé
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2926 HZDelft, The Netherlands
| | - Wiel H. Evers
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2926 HZDelft, The Netherlands
| | - Zeger Hens
- Department
of Chemistry and Center for Nano and Biophotonics, Ghent University, 9000Ghent, Belgium
| | - Arjan J. Houtepen
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2926 HZDelft, The Netherlands
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7
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Eren H, Bednarz RJR, Alimoradi Jazi M, Donk L, Gudjonsdottir S, Bohländer P, Eelkema R, Houtepen AJ. Permanent Electrochemical Doping of Quantum Dot Films through Photopolymerization of Electrolyte Ions. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2022; 34:4019-4028. [PMID: 35573106 PMCID: PMC9097154 DOI: 10.1021/acs.chemmater.2c00199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 04/14/2022] [Indexed: 06/15/2023]
Abstract
Quantum dots (QDs) are considered for devices like light-emitting diodes (LEDs) and photodetectors as a result of their tunable optoelectronic properties. To utilize the full potential of QDs for optoelectronic applications, control over the charge carrier density is vital. However, controlled electronic doping of these materials has remained a long-standing challenge, thus slowing their integration into optoelectronic devices. Electrochemical doping offers a way to precisely and controllably tune the charge carrier concentration as a function of applied potential and thus the doping levels in QDs. However, the injected charges are typically not stable after disconnecting the external voltage source because of electrochemical side reactions with impurities or with the surfaces of the QDs. Here, we use photopolymerization to covalently bind polymerizable electrolyte ions to polymerizable solvent molecules after electrochemical charge injection. We discuss the importance of using polymerizable dopant ions as compared to nonpolymerizable conventional electrolyte ions such as LiClO4 when used in electrochemical doping. The results show that the stability of charge carriers in QD films can be enhanced by many orders of magnitude, from minutes to several weeks, after photochemical ion fixation. We anticipate that this novel way of stable doping of QDs will pave the way for new opportunities and potential uses in future QD electronic devices.
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8
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Norton K, Jacobs J, Neilson J, Hopkinson D, Mokhtar MZ, Curry RJ, Lewis DJ. Preparation of solution processed photodetectors comprised of two-dimensional tin(ii) sulfide nanosheet thin films assembled via the Langmuir-Blodgett method. RSC Adv 2021; 11:26813-26819. [PMID: 35479979 PMCID: PMC9037678 DOI: 10.1039/d1ra04470b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 07/30/2021] [Indexed: 01/09/2023] Open
Abstract
We report the manufacture of fully solution processed photodetectors based on two-dimensional tin(ii) sulfide assembled via the Langmuir-Blodgett method. The method we propose can coat a variety of substrates including paper, Si/SiO2 and flexible polymer allowing for a potentially wide range of applications in future optoelectronic devices.
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Affiliation(s)
- Kane Norton
- Department of Materials, University of Manchester Oxford Road Manchester M13 9PL UK
| | - Janet Jacobs
- Photon Science Institute, Department of Electrical and Electronic Engineering, University of Manchester Oxford Road Manchester M13 9PL UK
| | - Joseph Neilson
- Department of Materials, University of Manchester Oxford Road Manchester M13 9PL UK
| | - David Hopkinson
- Department of Materials, University of Manchester Oxford Road Manchester M13 9PL UK
| | - Mohammad Z Mokhtar
- Department of Materials, University of Manchester Oxford Road Manchester M13 9PL UK
| | - Richard J Curry
- Photon Science Institute, Department of Electrical and Electronic Engineering, University of Manchester Oxford Road Manchester M13 9PL UK
| | - David J Lewis
- Department of Materials, University of Manchester Oxford Road Manchester M13 9PL UK
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9
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du Fossé I, Boehme SC, Infante I, Houtepen AJ. Dynamic Formation of Metal-Based Traps in Photoexcited Colloidal Quantum Dots and Their Relevance for Photoluminescence. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2021; 33:3349-3358. [PMID: 34054218 PMCID: PMC8154315 DOI: 10.1021/acs.chemmater.1c00561] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 04/09/2021] [Indexed: 05/11/2023]
Abstract
Trap states play a crucial role in the design of colloidal quantum dot (QD)-based technologies. The presence of these in-gap states can either significantly limit the efficiency of devices (e.g., in solar cells or LEDs) or play a pivotal role in the functioning of the technology (e.g., in catalysis). Understanding the atomistic nature of traps is therefore of the highest importance. Although the mechanism through which undercoordinated chalcogenide atoms can lead to trap states in II-VI QDs is generally well understood, the nature of metal-based traps remains more elusive. Previous research has shown that reduction of metal sites in negatively charged QDs can lead to in-gap states. Here, we use density functional theory to show that metal-based traps are also formed in charge-neutral but photoexcited CdSe QDs. It is found that Cd-Cd dimers and the concomitant trap states are transient in nature and appear and disappear on the picosecond time scale. Subsequent nonradiative recombination from the trap is shown to be much faster than radiative recombination, indicating that dimer-related trap states can quench the photoluminescence. These results are expected to be transferable to other II-VI materials and highlight the importance of surface redox reactions for the optical properties of QDs. Moreover, they show that photoexcitation can lead to atomic rearrangements on the surface and thus create transient in-gap states.
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Affiliation(s)
- Indy du Fossé
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Simon C. Boehme
- Laboratory
of Inorganic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1, 8093 Zürich, Switzerland
- Empa-Swiss
Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600 Dübendorf, Switzerland
| | - Ivan Infante
- Department
of Nanochemistry, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Arjan J. Houtepen
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
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10
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Prather KV, Lee S, Tsui EY. Metal-Carbonyl-Functionalized CdSe Nanocrystals: Synthesis, Surface Redox, and Infrared Intensities. Inorg Chem 2021; 60:4269-4277. [PMID: 33502193 DOI: 10.1021/acs.inorgchem.0c03641] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Characterizing the surfaces of colloidal semiconductor nanocrystals (NCs) remains a key challenge for understanding and controlling their physical properties and chemical behavior. For this reason, the development of new methods to study NC surfaces is of great interest. In this paper, we report the use of (Me3Si)2Fe(CO)4 and Et3SiCo(CO)4 as reagents for functionalizing CdSe NC surfaces with organometallic metal tetracarbonyl fragments. This method avoids NC surface reduction and can achieve high metal carbonyl surface densities. Surface reduction or oxidation, as well as changes to the surface stoichiometry, was shown to shift the metal carbonyl CO stretching frequencies, making these surface-bound metal carbonyl fragments useful spectroscopic reporters of NC surface chemistry. Normal coordinate analysis was used on the metal carbonyl CO stretching vibrations to study the electronic influence of the CdSe NCs on the transition-metal center of the metal carbonyl fragments. These studies demonstrate the utility of organometallic spectroscopic reporters in studying the surface chemistry of NCs.
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Affiliation(s)
- Keaton V Prather
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Seryeong Lee
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Emily Y Tsui
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
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11
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Calvin JJ, O'Brien EA, Sedlak AB, Balan AD, Alivisatos AP. Thermodynamics of Composition Dependent Ligand Exchange on the Surfaces of Colloidal Indium Phosphide Quantum Dots. ACS NANO 2021; 15:1407-1420. [PMID: 33404231 DOI: 10.1021/acsnano.0c08683] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Quantum dot surfaces can have a substantial effect on their physical, chemical, and optoelectronic properties. When the chemistry that occurs at the surface of nanocrystals is studied, critical insights can be gained into the fundamental structural, thermodynamic, and optical properties of quantum dot materials providing a valuable guide for how to best adapt them for desired applications. Colloidal quantum dots are often terminated with organic ligands that consist of a long aliphatic chain and a head group that binds tightly to the nanocrystal surface. While extensive work has been done to understand how ligand head groups influence quantum dot properties, studies to unravel the influence of the organic ligand tail on ligands and surface reaction equilibria are incomplete. To further investigate the driving forces of quantum dot surface modification, a series of ligand exchange reactions with oleic acid were performed on indium phosphide quantum dots, initially terminated with straight-chain carboxylates of variable lengths. The reaction was monitored using isothermal titration calorimetry and 1H NMR to determine the extent of each reaction and its associated thermodynamics. From these measurements, interligand interactions were observed to be dependent on the length of the straight-chain ligand. A modified Ising model was used to investigate the enthalpic and entropic effects contributing to these ligand exchanges and reveal that interligand interactions play a much larger role than previously thought. Additional experimentation with phosphonic acid ligand exchange reveals complexity in the reaction mechanism but further illustrates the significant impact of ligand tail group length on thermodynamics, even in cases where there is a large difference in head group binding energy.
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Affiliation(s)
- Jason J Calvin
- Material Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Erin A O'Brien
- Material Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | | | - Arunima D Balan
- Material Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - A Paul Alivisatos
- Material Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Kavli Energy NanoScience Institute, Berkeley, California 94720, United States
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12
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Hartley CL, Kessler ML, Dempsey JL. Molecular-Level Insight into Semiconductor Nanocrystal Surfaces. J Am Chem Soc 2021; 143:1251-1266. [PMID: 33442974 DOI: 10.1021/jacs.0c10658] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Semiconductor nanocrystals exhibit attractive photophysical properties for use in a variety of applications. Advancing the efficiency of nanocrystal-based devices requires a deep understanding of the physical defects and electronic states that trap charge carriers. Many of these states reside at the nanocrystal surface, which acts as an interface between the semiconductor lattice and the molecular capping ligands. While a detailed structural and electronic understanding of the surface is required to optimize nanocrystal properties, these materials are at a technical disadvantage: unlike molecular structures, semiconductor nanocrystals lack a specific chemical formula and generally must be characterized as heterogeneous ensembles. Therefore, in order for the field to improve current nanocrystal-based technologies, a creative approach to gaining a "molecular-level" picture of nanocrystal surfaces is required. To this end, an expansive toolbox of experimental and computational techniques has emerged in recent years. In this Perspective, we critically evaluate the insight into surface structure and reactivity that can be gained from each of these techniques and demonstrate how their strategic combination is already advancing our molecular-level understanding of nanocrystal surface chemistry.
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Affiliation(s)
- Carolyn L Hartley
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290, United States
| | - Melody L Kessler
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290, United States
| | - Jillian L Dempsey
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290, United States
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13
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Calvin JJ, Swabeck JK, Sedlak AB, Kim Y, Jang E, Alivisatos AP. Thermodynamic Investigation of Increased Luminescence in Indium Phosphide Quantum Dots by Treatment with Metal Halide Salts. J Am Chem Soc 2020; 142:18897-18906. [PMID: 33095575 DOI: 10.1021/jacs.0c08954] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Increasing the quantum yields of InP quantum dots is important for their applications, particularly for use in consumer displays. While several methods exist to improve quantum yield, the addition of inorganic metal halide salts has proven promising. To further investigate this phenomenon, InP quantum dots dispersed in tetrahydrofuran were titrated with ZnCl2, ZnBr2, and InCl3. The optical properties were observed, and the reactions were studied by using quantitative 1H NMR and thermodynamic measurements from isothermal titration calorimetry. These measurements contradict the previously hypothesized reaction mechanism in which metal halide salts, acting as Z-type ligands, passivate undercoordinated anions on the surface of the quantum dots. This work provides evidence for a newly proposed mechanism wherein the metal halide salts undergo a ligand exchange with indium myristate. Thermodynamic measurements prove key to supporting this new mechanism, particularly in describing the organic ligand interactions on the surface. An Ising model was used to simulate the quantum dot surface and was fit by using thermodynamic and 1H NMR data. Together, these data and the proposed exchange mechanism provide greater insight into the surface chemistry of quantum dots.
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Affiliation(s)
- Jason J Calvin
- Material Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Joseph K Swabeck
- Material Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | | | - Yongwook Kim
- Inorganic Material Lab, Samsung Advanced Institute of Technology, Samsung Electronics, 130 Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 16678, Republic of Korea
| | - Eunjoo Jang
- Inorganic Material Lab, Samsung Advanced Institute of Technology, Samsung Electronics, 130 Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 16678, Republic of Korea
| | - A Paul Alivisatos
- Material Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.,Kavli Energy NanoScience Institute, Berkeley, California 94720, United States
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14
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Vonk SW, Fridriksson MB, Hinterding SOM, Mangnus MJJ, van Swieten TP, Grozema FC, Rabouw FT, van der Stam W. Trapping and Detrapping in Colloidal Perovskite Nanoplatelets: Elucidation and Prevention of Nonradiative Processes through Chemical Treatment. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2020; 124:8047-8054. [PMID: 32421082 PMCID: PMC7217613 DOI: 10.1021/acs.jpcc.0c02287] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Indexed: 05/05/2023]
Abstract
Metal-halide perovskite nanocrystals show promise as the future active material in photovoltaics, lighting, and other optoelectronic applications. The appeal of these materials is largely due to the robustness of the optoelectronic properties to structural defects. The photoluminescence quantum yield (PLQY) of most types of perovskite nanocrystals is nevertheless below unity, evidencing the existence of nonradiative charge-carrier decay channels. In this work, we experimentally elucidate the nonradiative pathways in CsPbBr3 nanoplatelets, before and after chemical treatment with PbBr2 that improves the PLQY. A combination of picosecond streak camera and nanosecond time-correlated single-photon counting measurements is used to probe the excited-state dynamics over 6 orders of magnitude in time. We find that up to 40% of the nanoplatelets from a synthesis batch are entirely nonfluorescent and cannot be turned fluorescent through chemical treatment. The other nanoplatelets show fluorescence, but charge-carrier trapping leads to losses that are prevented by chemical treatment. Interestingly, even without chemical treatment, some losses due to trapping are mitigated because trapped carriers spontaneously detrap on nanosecond-to-microsecond timescales. Our analysis shows that multiple nonradiative pathways are active in perovskite nanoplatelets, which are affected differently by chemical treatment with PbBr2. More generally, our work highlights that in-depth studies using a combination of techniques are necessary to understand nonradiative pathways in fluorescent nanocrystals. Such understanding is essential to optimize synthesis and treatment procedures.
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Affiliation(s)
- Sander
J. W. Vonk
- Debye
Institute for Nanomaterials Science, Utrecht
University, Princetonplein 1, 3584 CC Utrecht, The Netherlands
| | - Magnus B. Fridriksson
- Opto-Electronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Stijn O. M. Hinterding
- Debye
Institute for Nanomaterials Science, Utrecht
University, Princetonplein 1, 3584 CC Utrecht, The Netherlands
| | - Mark J. J. Mangnus
- Debye
Institute for Nanomaterials Science, Utrecht
University, Princetonplein 1, 3584 CC Utrecht, The Netherlands
| | - Thomas P. van Swieten
- Debye
Institute for Nanomaterials Science, Utrecht
University, Princetonplein 1, 3584 CC Utrecht, The Netherlands
| | - Ferdinand C. Grozema
- Opto-Electronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Freddy T. Rabouw
- Debye
Institute for Nanomaterials Science, Utrecht
University, Princetonplein 1, 3584 CC Utrecht, The Netherlands
| | - Ward van der Stam
- Opto-Electronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, The Netherlands
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15
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Baturin V, Lepeshkin S, Bushlanova N, Uspenskii Y. Atomistic origins of charge traps in CdSe nanoclusters. Phys Chem Chem Phys 2020; 22:26299-26305. [PMID: 33175940 DOI: 10.1039/d0cp05139j] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Constructing trap-free nanomaterials is a challenge that requires a fundamental understanding of the trapping phenomenon, especially the structural features responsible for electronic localization. Previously, such trapping configurations were explored by manual insertion of surface defects according to researchers' intuition, e.g. Cd-Se-Cd moiety [Houtepen et al., Chem. Mater., 2017, 29, 752]. In this study we report new types of traps in CdSe nanoclusters, including the metal-based one, which were found using a novel, unbiased approach. Namely, we screened a vast number of globally optimized CdnSem clusters (n,m ≤ 15) for localized electronic states. These systems model the wide diversity of defects in unpassivated areas of a nanocluster surface, while still being accessible for ab initio global optimization. Despite this variety, all 39 traps we found fall into 3 types, including two new ones. Such a reduction shows the universal character of discovered traps, irrelevant to the global structure of a cluster. Many of these traps not only have newly reported atomic arrangements, but also original confinement mechanisms which are explained at the atomistic level. We found that the relaxation and global optimization of the cluster structure greatly reduce the number of traps and push the trap energies from midgap to the near-gap edge positions, which agrees with the spectral measurements of II-VI semiconductor nanocrystals.
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Affiliation(s)
- Vladimir Baturin
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30, bld. 1, Moscow 121205, Russia.
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16
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Yin J, Cogan NMB, Burke R, Hou Z, Sowers KL, Krauss TD. Size dependence of photocatalytic hydrogen generation for CdTe quantum dots. J Chem Phys 2019; 151:174707. [DOI: 10.1063/1.5125000] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Affiliation(s)
- Jiajia Yin
- Institute of Optics and Electronics Chinese Academy Science, Chengdu, Sichuan 610209, China
| | - Nicole M. B. Cogan
- Department of Chemistry, University of Rochester, Rochester, New York 14627, USA
| | - Rebeckah Burke
- Department of Chemistry, University of Rochester, Rochester, New York 14627, USA
| | - Zhentao Hou
- Department of Chemistry, University of Rochester, Rochester, New York 14627, USA
| | - Kelly L. Sowers
- Department of Chemistry, University of Rochester, Rochester, New York 14627, USA
| | - Todd D. Krauss
- Department of Chemistry, University of Rochester, Rochester, New York 14627, USA
- The Institute of Optics, University of Rochester, Rochester, New York 14627, USA
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17
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van der Stam W, Grimaldi G, Geuchies JJ, Gudjonsdottir S, van Uffelen PT, van Overeem M, Brynjarsson B, Kirkwood N, Houtepen AJ. Electrochemical Modulation of the Photophysics of Surface-Localized Trap States in Core/Shell/(Shell) Quantum Dot Films. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2019; 31:8484-8493. [PMID: 31666761 PMCID: PMC6814269 DOI: 10.1021/acs.chemmater.9b02908] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 09/23/2019] [Indexed: 05/03/2023]
Abstract
In this work, we systematically study the spectroelectrochemical response of CdSe quantum dots (QDs), CdSe/CdS core/shell QDs with varying CdS shell thicknesses, and CdSe/CdS/ZnS core/shell/shell QDs in order to elucidate the influence of localized surface trap states on the optoelectronic properties. By correlating the differential absorbance and the photoluminescence upon electrochemically raising the Fermi level, we reveal that trap states near the conduction band (CB) edge give rise to nonradiative recombination pathways regardless of the CdS shell thickness, evidenced by quenching of the photoluminescence before the CB edge is populated with electrons. This points in the direction of shallow trap states localized on the CdS shell surface that give rise to nonradiative recombination pathways. We suggest that these shallow trap states reduce the quantum yield because of enhanced hole trapping when the Fermi level is raised electrochemically. We show that these shallow trap states are removed when additional wide band gap ZnS shells are grown around the CdSe/CdS core/shell QDs.
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18
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Gudjonsdottir S, Koopman C, Houtepen AJ. Enhancing the stability of the electron density in electrochemically doped ZnO quantum dots. J Chem Phys 2019; 151:144708. [DOI: 10.1063/1.5124534] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Solrun Gudjonsdottir
- Chemical Engineering, Optoelectronic Materials, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Christel Koopman
- Chemical Engineering, Optoelectronic Materials, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Arjan J. Houtepen
- Chemical Engineering, Optoelectronic Materials, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
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19
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Kozlov OV, Park YS, Roh J, Fedin I, Nakotte T, Klimov VI. Sub–single-exciton lasing using charged quantum dots coupled to a distributed feedback cavity. Science 2019; 365:672-675. [DOI: 10.1126/science.aax3489] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 07/12/2019] [Indexed: 01/07/2023]
Abstract
Colloidal semiconductor quantum dots (QDs) are attractive materials for realizing highly flexible, solution-processable optical gain media, but they are difficult to use in lasing because of complications associated with extremely short optical-gain lifetimes limited by nonradiative Auger recombination. By combining compositional grading of the QD’s interior for hindering Auger decay with postsynthetic charging for suppressing parasitic ground-state absorption, we can reduce the lasing threshold to values below the single-exciton-per-dot limit. As a favorable departure from traditional multi-exciton–based lasing schemes, our approach should facilitate the development of solution-processable lasing devices and thereby help to extend the reach of lasing technologies into areas not accessible with traditional, epitaxially grown semiconductor materials.
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20
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du Fossé I, ten Brinck S, Infante I, Houtepen AJ. Role of Surface Reduction in the Formation of Traps in n-Doped II-VI Semiconductor Nanocrystals: How to Charge without Reducing the Surface. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2019; 31:4575-4583. [PMID: 31274957 PMCID: PMC6595709 DOI: 10.1021/acs.chemmater.9b01395] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 05/25/2019] [Indexed: 05/19/2023]
Abstract
The efficiency of nanocrystal (NC)-based devices is often limited by the presence of surface states that lead to localized energy levels in the bandgap. Yet, a complete understanding of the nature of these traps remains challenging. Although theoretical modeling has greatly improved our comprehension of the NC surface, several experimental studies suggest the existence of metal-based traps that have not yet been found with theoretical methods. Since there are indications that these metal-based traps form in the presence of excess electrons, the present work uses density functional theory (DFT) calculations to study the effects of charging II-VI semiconductor NCs with either full or imperfect surface passivation. It is found that charge injection can lead to trap-formation via two pathways: metal atom ejection from perfectly passivated NCs or metal-metal dimer-formation in imperfectly passivated NCs. Fully passivated CdTe NCs are observed to be stable up to a charge of two electrons. Further reduction leads to charge localization on a surface Cd atom and the formation of in-gap states. The effects of suboptimal passivation are probed by charging NCs where an X-type ligand is removed from the (100) plane. In this case, injection of even one electron leads to Cd-dimerization and trap-formation. Addition of an L-type amine ligand prevents this dimer-formation and is suggested to also prevent trapping of photoexcited electrons in charge neutral NCs. The results presented in this work are generalized to NCs of different sizes and other II-VI semiconductors. This has clear implications for n-doping II-VI semiconductor NCs without introducing surface traps due to metal ion reduction. The possible effect of these metal ion localized traps on the photoluminescence efficiency of neutral NCs is also discussed.
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Affiliation(s)
- Indy du Fossé
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Stephanie ten Brinck
- Department
of Theoretical Chemistry, Faculty of Science, Vrije Universiteit Amsterdam, de Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
| | - Ivan Infante
- Department
of Theoretical Chemistry, Faculty of Science, Vrije Universiteit Amsterdam, de Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
- Department
of Nanochemistry, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
- E-mail:
| | - Arjan J. Houtepen
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
- E-mail:
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21
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Grimaldi G, Geuchies JJ, van der Stam W, du Fossé I, Brynjarsson B, Kirkwood N, Kinge S, Siebbeles LD, Houtepen AJ. Spectroscopic Evidence for the Contribution of Holes to the Bleach of Cd-Chalcogenide Quantum Dots. NANO LETTERS 2019; 19:3002-3010. [PMID: 30938530 PMCID: PMC6509645 DOI: 10.1021/acs.nanolett.9b00164] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 03/22/2019] [Indexed: 05/20/2023]
Abstract
In transient absorption (TA) measurements on Cd-chalcogenide quantum dots (QDs), the presence of a band-edge (BE) bleach signal is commonly attributed entirely to conduction-band electrons in the 1S(e) state, neglecting contributions from BE holes. While this has been the accepted view for more than 20 years, and has often been used to distinguish electron and hole kinetics, the reason for the absence of a hole contribution to the BE-bleach has remained unclear. Here, we show with three independent experiments that holes do in fact have a significant impact on the BE-bleach of well-passivated Cd-chalcogenide QD samples. Transient absorption experiments on high photoluminescence quantum yield CdSe/CdS/ZnS core-shell-shell QDs clearly show an increase of the band-edge bleach as holes cool down to the band edge. The relative contribution of electron-to-hole bleach is 2:1, as predicted by theory. The same measurements on core-only CdSe QDs with a lower quantum yield do not show a contribution of holes to the band-edge bleach. We assign the lack of hole bleach to the presence of ultrafast hole trapping in samples with insufficient passivation of the QD surface. In addition, we show measurements of optical gain in core-shell-shell QD solutions, providing clear evidence of a significant hole contribution to the BE transient absorption signal. Finally, we present spectroelectrochemical measurements on CdTe QDs films, showing the presence of a BE-bleach for both electron and hole injections. The presence of a contribution of holes to the bleach in passivated Cd-chalcogenides QDs bears important implications for quantitative studies on optical gain as well as for TA determinations of carrier dynamics.
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Affiliation(s)
- Gianluca Grimaldi
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, HAZ Delft 2629, The Netherlands
- E-mail:
| | - Jaco J. Geuchies
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, HAZ Delft 2629, The Netherlands
- E-mail:
| | - Ward van der Stam
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, HAZ Delft 2629, The Netherlands
| | - Indy du Fossé
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, HAZ Delft 2629, The Netherlands
| | - Baldur Brynjarsson
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, HAZ Delft 2629, The Netherlands
| | - Nicholas Kirkwood
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, HAZ Delft 2629, The Netherlands
| | - Sachin Kinge
- Materials
Research & Development, Toyota Motor
Europe, Hoge Wei 33, Zaventem B-1930, Belgium
| | - Laurens D.A. Siebbeles
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, HAZ Delft 2629, The Netherlands
| | - Arjan J. Houtepen
- Optoelectronic
Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, HAZ Delft 2629, The Netherlands
- E-mail:
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22
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Garoz‐Ruiz J, Perales‐Rondon JV, Heras A, Colina A. Spectroelectrochemistry of Quantum Dots. Isr J Chem 2019. [DOI: 10.1002/ijch.201900028] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Jesus Garoz‐Ruiz
- Department of ChemistryUniversidad de Burgos Pza. Misael Bañuelos s/n E-09001 Burgos Spain
| | - Juan V. Perales‐Rondon
- Department of ChemistryUniversidad de Burgos Pza. Misael Bañuelos s/n E-09001 Burgos Spain
| | - Aranzazu Heras
- Department of ChemistryUniversidad de Burgos Pza. Misael Bañuelos s/n E-09001 Burgos Spain
| | - Alvaro Colina
- Department of ChemistryUniversidad de Burgos Pza. Misael Bañuelos s/n E-09001 Burgos Spain
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23
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Weber M, Westendorf S, Märker B, Braun K, Scheele M. Opportunities and challenges for electrochemistry in studying the electronic structure of nanocrystals. Phys Chem Chem Phys 2019; 21:8992-9001. [DOI: 10.1039/c9cp00301k] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We review the state-of-the-art of determining the electronic structure of nanocrystals in thin films by electrochemistry and emphasize the benefits of correlating electrochemical with spectroscopic methods to this end.
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Affiliation(s)
- Michelle Weber
- Institute of Physical and Theoretical Chemistry
- University of Tübingen
- Auf der Morgenstelle 18
- 72076 Tübingen
- Germany
| | - Sophia Westendorf
- Institute of Physical and Theoretical Chemistry
- University of Tübingen
- Auf der Morgenstelle 18
- 72076 Tübingen
- Germany
| | - Björn Märker
- Institute of Physical and Theoretical Chemistry
- University of Tübingen
- Auf der Morgenstelle 18
- 72076 Tübingen
- Germany
| | - Kai Braun
- Institute of Physical and Theoretical Chemistry
- University of Tübingen
- Auf der Morgenstelle 18
- 72076 Tübingen
- Germany
| | - Marcus Scheele
- Institute of Physical and Theoretical Chemistry
- University of Tübingen
- Auf der Morgenstelle 18
- 72076 Tübingen
- Germany
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