Article
Chemistry, Multidisciplinary
Ji Yang, Huicheng Hu, Yifei Lv, Mohan Yuan, Binbin Wang, Ziyang He, Shiwu Chen, Ya Wang, Zhixiang Hu, Mengxuan Yu, Xingchen Zhang, Jungang He, Jianbing Zhang, Huan Liu, Hsien-Yi Hsu, Jiang Tang, Haisheng Song, Xinzheng Lan
Summary: This study reports a ligand-engineered approach to synthesize well-separated HgTe CQDs. By using specific ligands, highly monodisperse HgTe CQDs with a wide size range covering the infrared regions were successfully synthesized, achieving excellent electron mobility and detectivity.
Article
Chemistry, Multidisciplinary
Ozan Atan, Joao M. Pina, Darshan H. Parmar, Pan Xia, Yangning Zhang, Ahmet Gulsaran, Eui Dae Jung, Dongsun Choi, Muhammad Imran, Mustafa Yavuz, Sjoerd Hoogland, Edward H. Sargent
Summary: Solution-processed colloidal quantum dots (CQDs) are promising materials for short-wavelength infrared (SWIR) photodetectors. However, the low carrier mobility of CQD-based hole transport layers (HTL) limits the photodiode response speed. By employing NiOx as the HTL in inverted SWIR photodetectors, we achieve 4x shorter fall times compared to CQDs treated with 1,2-ethanedithiol (EDT). Optoelectronic simulations show that the high carrier mobility of NiOx enhances the electric field in the active layer, reducing transport time and increasing photodetector response time.
Article
Chemistry, Multidisciplinary
I. K. M. Reaz Rahman, Shiekh Zia Uddin, Matthew Yeh, Naoki Higashitarumizu, Jongchan Kim, Quanwei Li, Hyeonjun Lee, Kyuho Lee, Hoyeon Kim, Cheolmin Park, Jaehoon Lim, Joel W. Ager III, Ali Javey
Summary: In this study, a metal-oxide-semiconductor capacitor based on CdSe/CdS quantum dot thin films was used to investigate the influence of background charge on the luminescence efficiency and lifetime. By applying a gate voltage, the concentration ratio of charged and neutral quasiparticles in the quantum dots can be controlled, leading to modulation of the photoluminescence intensity and effective lifetime. The findings have potential applications in voltage-controlled electrochromics.
Article
Chemistry, Multidisciplinary
Pip C. J. Clark, Nathan K. Lewis, Jack Chun-Ren Ke, Ruben Ahumada-Lazo, Qian Chen, Darren C. J. Neo, E. Ashley Gaulding, Gregory F. Pach, Igor Pis, Mathieu G. Silly, Wendy R. Flavell
Summary: Depletion regions are found at the surface of n and p-type CQD solids with different ligand treatments, indicating that carrier dynamics timescales in the surface can vary due to the presence of oxygen contaminants.
Article
Nanoscience & Nanotechnology
Wei Gong, Peng Wang, Wenjie Deng, Xiaobo Zhang, Boxing An, Jingjie Li, Zhaoqing Sun, Dichao Dai, Zekang Liu, Jingzhen Li, Yongzhe Zhang
Summary: This study elucidates that noise current is the predominant factor limiting specific detectivity (D*) in lead sulfide colloidal quantum dot photodetectors. The noise is highly dependent on the trap densities in halide-passivated PbS films and the carriers injected from the Schottky contact. The research findings provide guidance to improve the design of high-performance colloidal quantum dot photodetectors.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Biochemistry & Molecular Biology
Lucas Cuadra, Sancho Salcedo-Sanz, Jose Carlos Nieto-Borge
Summary: This paper presents a network model for studying the transport behavior of electrons and holes in IB solar cells, and proposes a design constraint of reducing carrier effective mass and inter-dot distance to increase transport efficiency.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Nanoscience & Nanotechnology
Naoto Kumagai, Xiangmeng Lu, Yasuo Minami, Takahiro Kitada, Toshiro Isu
Summary: The study focused on determining the lateral mobility of photocarriers and activation energy of the photocurrent in stacked InAs quantum dot layers, which are crucial for photoconductive antennas operating for THz wave detection.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2021)
Article
Physics, Applied
Shikha Srivastava, Yashowanta N. Mohapatra
Summary: Layered molybdenum disulfide (MoS2) shows nontrivial departures in electrical properties compared to isotropic crystalline materials. The inter-layer mobility in mechanically exfoliated MoS2 flakes was experimentally studied, revealing impurity scattering as the dominant mechanism limiting mobility. The results provide insight into carrier transport engineering and design strategies based on MoS2 flakes.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Energy & Fuels
David Krisztian, Ferenc Korsos, Gergely Havasi
Summary: For the first time, the transient, steady-state, and small perturbation photoconductance decay lifetime measurement methods have been successfully combined into a single system. These three modes of operation complement each other and improve the accuracy of each measurement by compensating for their individual limitations. The combination of these methods provides accurate carrier lifetime data and the sum of excess carrier mobilities, which is crucial for high injection levels in modern solar cells where existing mobility models exhibit significant differences.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2023)
Article
Chemistry, Multidisciplinary
Xingyu Shen, John C. Peterson, Philippe Guyot-Sionnest
Summary: Mid-infrared HgTe colloidal quantum dot electroluminescent devices with high external quantum efficiency and power conversion efficiency were demonstrated. The power conversion efficiency was improved by reducing the resistance of the transparent electrode through the incorporation of a metal conductive grid.
Article
Chemistry, Multidisciplinary
Changjo Kim, Irem Kozakci, Sang Yeon Lee, Byeongsu Kim, Junho Kim, Jihyung Lee, Boo Soo Ma, Eun Sung Oh, Taek-Soo Kim, Jung-Yong Lee
Summary: This study proposes a facile approach to improve the mechanical stability of CQD solar cells without compromising the high power conversion efficiency. By introducing (3-aminopropyl)triethoxysilane (APTS) on CQD films, the dot-to-dot bonding is strengthened, making the treated devices robust to mechanical stress. The device maintains 88% of the initial PCE under 12,000 cycles at a bending radius of 8.3 mm and achieves a PCE of 11.04%, one of the highest PCEs in flexible PbS CQD solar cells.
Article
Nanoscience & Nanotechnology
Nikola Dordevic, Raphael Schwanninger, Maksym Yarema, Stefan Koepfli, Olesya Yarema, Yannick Salamin, Nolan Lassaline, Bojun Cheng, Nuri Yazdani, Alexander Dorodnyy, Yuriy Myronovych Fedoryshyn, Vanessa Wood, Juerg Leuthold
Summary: Efficient and engineered photodetectors using colloidal quantum dots and metasurface enhancement are reported. The photodetectors and photodiodes showed high responsivities and faster responses, thanks to the metasurface design. The metasurface improved the absorption and enabled photogain, resulting in high performance photoconductors and photodiodes.
Article
Chemistry, Physical
Jannik Rebmann, Hans Werners, Florian Johst, Marcel Dohrmann, Yannic U. Staechelin, Christian Strelow, Alf Mews, Tobias Kipp
Summary: Cation exchange occurs during the synthesis of colloidal semiconductor heteronanoparticles, affecting their band gap and optoelectronic properties. The role of cation exchange during the growth of anisotropic dot-in-rod structures was studied. The dominant process in the initial stages of the shell-growth reaction was found to be cation exchange from ZnSe to CdSe.
CHEMISTRY OF MATERIALS
(2023)
Article
Engineering, Electrical & Electronic
Sobia Waheed, Saurabh Pareek, T. Abhijith, Rakesh Suthar, Punit Sharma, Supravat Karak
Summary: In this study, the influences of in-situ substrate temperature and acoustic substrate vibration on the charge carrier dynamics of spray-coated polymer solar cells were investigated. The results showed that the performance of the devices significantly improved under the simultaneous application of substrate temperature and acoustic vibration, with reduced surface roughness and droplet boundaries.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2022)
Article
Engineering, Environmental
Ruiqi Guo, Jie Meng, Weihua Lin, Aqiang Liu, Tonu Pullerits, Kaibo Zheng, Jianjun Tian
Summary: Doping transition metal manganese ions (Mn2+) into CuInSe2 (CISe) quantum dots improves crystal quality, extends charge carrier lifetime, and results in photodetectors with high responsivity and detection performance.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Nima Taghipour, Guy L. Whitworth, Andreas Othonos, Mariona Dalmases, Santanu Pradhan, Yongjie Wang, Gaurav Kumar, Gerasimos Konstantatos
Summary: A binary blend of CQDs and ZnO nanocrystals is used to passivate trap states in PbS-CQD gain medium, leading to improved Auger lifetime and suppression of trap-assisted Auger recombination. Integration of this binary blend with a DFB resonator has demonstrated stable single-mode lasing emission with low threshold and continuous operation of 5 hours under room temperature and ambient conditions.
ADVANCED MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Avijit Saha, Gaurav Kumar, Santanu Pradhan, Gauttam Dash, Ranjani Viswanatha, Gerasimos Konstantatos
Summary: Selective spectral detection of ultraviolet (UV) radiation is highly important in various fields, and this study introduces a quantum dot-based sensing scheme that expands the spectral coverage of silicon complementary metal-oxide-semiconductor (CMOS) sensors into the UV range, enabling efficient UV detection without affecting visible and UV-band discrimination.
ADVANCED MATERIALS
(2022)
Article
Optics
Yongjie Wang, Sean R. Kavanagh, Ignasi Burgues-Ceballos, Aron Walsh, David Scanlon, Gerasimos Konstantatos
Summary: This study investigates the enhanced optical absorption of a ternary chalcogenide semiconductor through engineering cation disorder, which enables the development of highly efficient extremely thin absorber photovoltaic devices. The experimental results demonstrate that colloidal nanocrystals with engineered cation disorder show a significantly higher absorption coefficient compared to other photovoltaic materials, offering a promising solution for environmentally friendly and solution-processed solar cells.
Correction
Optics
Yongjie Wang, Sean R. Kavanagh, Ignasi Burgues-Ceballos, Aron Walsh, David O. Scanlon, Gerasimos Konstantatos
Article
Chemistry, Physical
Yongjie Wang, Lucheng Peng, Zhuoran Wang, Gerasimos Konstantatos
Summary: Silver bismuth sulfide nanocrystals prepared by solution-phase ligand exchange exhibit fully environmentally friendly characteristics and demonstrate high power conversion efficiency, making them promising for low-cost solar cell applications.
ADVANCED ENERGY MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Santanu Pradhan, Mariona Dalmases, Nima Taghipour, Biswajit Kundu, Gerasimos Konstantatos
Summary: Developing high performance, low-cost solid-state light emitters in the telecom wavelength bandwidth is crucial for infrared light-based communications. In this study, the authors report highly efficient SWIR CQD LEDs with a record EQE of 11.8%, which further increased to 18.6% by optimizing the optical out-coupling. The CQD LED also has an electrical bandwidth of 2 MHz, making it suitable for SWIR free-space optical transmission.
Article
Electrochemistry
Justyna Piwek, Adam Slesinski, Krzysztof Fic, Sergio Aina, Alen Vizintin, Blaz Tratnik, Elena Tchernychova, Maria Pilar Lobera, Maria Bernechea, Robert Dominko, Elzbieta Frackowiak
Summary: This study presents an electrode material with enhanced power and high capacitance, which is obtained from carbonized adenine precursor. The carbon material exhibits a micro/mesoporous structure with optimal pore size ratio and high surface area. The carbon/carbon symmetric capacitor shows good electrochemical response and cyclability, indicating its potential for high-power stationary applications.
ELECTROCHIMICA ACTA
(2022)
Article
Chemistry, Multidisciplinary
Zhuoran Wang, Yongjie Wang, Nima Taghipour, Lucheng Peng, Gerasimos Konstantatos
Summary: Thin-film photovoltaic materials, specifically kesterite or Cu2ZnSn(S,Se)(4), offer a sustainable solution to environmental and energy challenges. This study pioneers the use of a superstrate configuration and the application of an Ag-refining step to achieve a Cd-free kesterite solar cell with a record high efficiency of 9.7%. The promoted grain growth and improved charge transport kinetics contribute to the performance boost.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Nima Taghipour, Mariona Dalmases, Guy L. Whitworth, Miguel Dosil, Andreas Othonos, Sotirios Christodoulou, Shanti Maria Liga, Gerasimos Konstantatos
Summary: This study utilizes PbS/PbSSe core/alloyed-shell colloidal quantum dots (CQDs) as a gain medium for infrared laser devices. The researchers achieved highly suppressed Auger recombination and lower amplified spontaneous emission (ASE) threshold by doping these engineered CQDs and successfully achieved near-infrared laser emission.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Physical
Sean R. Kavanagh, Christopher N. Savory, Shanti M. Liga, Gerasimos Konstantatos, Aron Walsh, David O. Scanlon
Summary: Perovskite-inspired materials have emerged as promising candidates for low-cost, nontoxic, and earth-abundant photovoltaic materials. However, theoretical investigations often overestimate the band gaps of these materials.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Green & Sustainable Science & Technology
Ignacio Cazcarro, Sergio Villamayor-Tomas, Maria Pilar Lobera, Joaquin Murria, Maria Bernechea
Summary: In this article, the governance of point-source water pollution in the European agri-food sector is analyzed, focusing on the case study of the wine industry in Aragon (Spain) using the networks of action situations approach. The strategic decisions of wine producers regarding water discharge regulations compliance are explored, and the feasibility and effectiveness of potential solutions are examined. The problem of peak load discharges in the sector is found to be influenced by the strategic behavior of wine producers, enforcement deficits, specificities of wine production, and controversies surrounding public treatment plants. Coordination between wine producers and treatment plant managers, along with economic incentives and stricter enforcement, would be necessary for promising solutions.
SUSTAINABILITY SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Nima Taghipour, Mariona Dalmases, Guy Luke Whitworth, Yongjie Wang, Gerasimos Konstantatos
Summary: Achieving low-threshold infrared stimulated emission in solution-processed quantum dots is critical for real-life applications. This Letter demonstrates the potential of ultra-low-threshold infrared stimulated emission using cascade charge transfer (CT) in Pb-chalcogenide colloidal quantum dot (CQD) solids.
Article
Chemistry, Multidisciplinary
Shanti Maria Liga, Yongjie Wang, Gerasimos Konstantatos
Summary: Cs2TiBr6 is a promising material that can be used as a lead-free alternative in photovoltaics. However, its instability in air has been a challenge, limiting further improvements and raising concerns about practical implementation. This study presents a method to enhance the stability of Cs2TiBr6 NCs by using SnBr4 in a simple surface treatment.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Adam Slesinski, Sylwia Sroka, Sergio Aina, Justyna Piwek, Krzysztof Fic, M. Pilar Lobera, Maria Bernechea, Elzbieta Frackowiak
Summary: The concept of a double-redox electrochemical capacitor operating in an aqueous electrolyte is proposed in this paper. The redox activity of sulphur from insoluble Bi2S3 nanocrystals is demonstrated, and the use of MPA as a ligand attached to the surface of the nanocrystals significantly boosts the performance. The combination of redox activity and iodide reactions enables the formation of a discharge voltage plateau, effectively boosting the capacitance and specific energy of the device.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Chemistry, Multidisciplinary
Ignasi Burgues-Ceballos, Yongjie Wang, Gerasimos Konstantatos
Summary: The study combines small-size and large-size AgBiS2 nanocrystals to optimize the band alignment in photovoltaic and photodetector devices. By fabricating a gradient absorbing layer, the charge transfer and transport efficiency of the devices are improved, achieving promising performance.
