Article
Chemistry, Physical
Bin Bin Jin, Shu Ying Kong, Guo Qing Zhang, Xing Qiao Chen, Hong Shan Ni, Fan Zhang, Dan Jun Wang, Jing Hui Zeng
Summary: The study focuses on inhibiting interfacial charge recombination in CdSe QDSSCs by constructing a ZnS/QDs/ZnS double-layer barrier structure and applying an electric field in VASILAR, achieving higher efficiency.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2021)
Article
Chemistry, Physical
Zeping Li, Xiong Yu, Yunhao Zhu, Sisi Liu, Xiaoyan Wen, Haifei Lu, Cong Wang, Xiao Li, Ming-Yu Li, Yingping Yang
Summary: In this study, ZnO quantum dot (QD) / magnetron sputtered ZnO homojunction photodetectors with excellent performance were fabricated by systematically varying the thickness ratios between two ZnO layers. The balanced ratio resulted in extra adsorption-desorption sites from the ZnO QDs and accelerated carrier transportation from the highly crystallized magnetron sputtered ZnO layers. As a result, the fabricated ZnO homojunction photodetector showed significantly increased responsivity and external quantum efficiency, paving the way for ultra-sensitive UV photodetection.
APPLIED SURFACE SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
Jagriti Tyagi, Himanshu Gupta, L. P. Purohit
Summary: Different photoanodes were prepared on fluorine-doped tin oxide conductive glass substrate using the doctor blade method, with CdS quantum dots deposited by SILAR. The ZnO/TiO2 photoanode achieved higher efficiency compared to bare TiO2 in the QDSSC, with improved electron transport and overall performance. The IPCE for ZnO/TiO2 electrode was approximately 46%, showing enhanced capabilities for photon-to-current conversion.
Article
Electrochemistry
Di Zhang, Sidong Zhang, Yanyan Fang, Dongmei Xie, Xiaowen Zhou, Yuan Lin
Summary: Introducing bifunctional linkers between TiO2 electrodes and quantum dots was an effective approach for the preparation of quantum dot-sensitized solar cells. Three types of linkers were studied, with phenyl MBA-TiO2 electrodes achieving the highest Cd content and PCE. The modified TiO2 electrodes showed lower electron recombination rates and higher efficiency, demonstrating the importance of linker selection for QDSCs design and optimization.
ELECTROCHIMICA ACTA
(2021)
Article
Chemistry, Multidisciplinary
Yuhan Gao, Qin Xue, Guohua Xie
Summary: This study introduces a thermally activated delayed fluorescence (TADF) polymer into the emitting layer of quantum dot light emitting diodes (QLEDs) to simplify the device structure and promote fluorescence resonance energy transfer. By optimizing the host selection, the emission from the TADF polymer itself can be suppressed, significantly improving the color purity of QLEDs. The fabricated CdZnS/ZnS core/shell red QLEDs, without using any hole transport layer, achieved a maximum external quantum efficiency of 18.1%. The cascaded energy transfer in the ternary emitting layer provides a promising strategy for constructing highly efficient and simplified QLEDs.
MATERIALS CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Physical
Siti Utari Rahayu, Yu-Rou Wang, Jen-Bin Shi, Ming-Way Lee
Summary: In this study, we report the fabrication and photovoltaic performance of new type-II AgInS2/CdSe core/shell quantum dot-sensitized solar cells. By growing a CdSe shell on an AgInS2 core, the photovoltaic efficiency is significantly improved. The AgInS2/CdSe cell achieves a power conversion efficiency of 8.39% under 1 sun, which is significantly higher than the single-layered AgInS2 and CdSe cells.
SUSTAINABLE ENERGY & FUELS
(2023)
Article
Physics, Applied
Shuning Wang, Maojun Zheng, Dongkai Jiang, Hao Yuan, Hao Chen, Yunlong Fan, Fanggang Li, Wenlan Zhang, Li Ma, Wenzhong Shen
Summary: Zinc oxide (ZnO) is a promising UV detector material with advantages of wide bandgap, rich resources, simple preparation, and environmental friendliness. However, its complicated preparation processes and complex device structures have limited its application. In this study, a high-performance UV detector based on graphene quantum dot-sensitized GaP@ZnO nanocomposite was successfully fabricated using a simple spin-coating method. This research provides a new method for preparing high-performance optoelectronic devices using material composites and surface modification.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Article
Energy & Fuels
Wenlei Lv, Yilong Lei, Jianping Deng, Junfei Fang, Wendeng Huang
Summary: Metal ion doping is an effective method to improve the optical and electrical properties of quantum dots (QDs). In this study, Zn-doped CdS and CdSe QDs were synthesized using the SILAR method and utilized in the construction of sensitized solar cells (QDSSCs). The results showed that Zn doping significantly enhanced the power conversion efficiency (PCE) of the QDSSCs by improving the current density, open-circuit voltage, and light absorbance. The Zn doping also reduced the interfacial charge recombination rate and prolonged the electron lifetime, resulting in more efficient charge collection in the QDSSCs.
Article
Engineering, Electrical & Electronic
Yexin Chen, Shibing Zou, Wenhua Zou, Dongyang Wang, Junhong Duan, Weiqing Liu, Huaming Wu
Summary: In this study, different ligands including oleic acid (OA), oleylamine and tri-n-octylphosphine (OAm-TOP), and OA-TOP were utilized for the synthesis of CdSe quantum dots (QDs). The effects of these ligands on the photovoltaic performance of CdSe QD-sensitized solar cells (QDSCs) were systematically investigated. It was found that CdSe QDs coated with OAm-TOP or OA-TOP exhibited an extended absorption range compared to those coated with OA, as confirmed by UV-vis absorption spectra. Electrochemical impedance spectroscopy (EIS) analysis revealed that CdSe QDs synthesized with OAm-TOP or OA-TOP effectively passivated surface defects, leading to an improvement in the photoelectric conversion efficiency (PCE) of the devices. The optimized PCE of 3.6% was achieved for CdSe QDSCs modified with OAm-TOP.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Nanoscience & Nanotechnology
Tianchen Jiang, Xin Liu, Jianbo Sun
Summary: ZnO quantum dots sensitized SnO2 porous nanowires were fabricated and designed for UV excitation gas sensor. The ZnO/SnO2 composite (SZQ1%) showed excellent sensing properties to NO2 gas under UV irradiation, with a detection limit of 100 ppb. The humidity stability of SZQ1% was also measured and discussed.
Article
Materials Science, Multidisciplinary
Denglin Zhao, Yueting Zheng, Tingtao Meng, Yangbin Zhu, Jipeng Jing, Xiang Chen, Hongjin Gao, Chaomin Mao, Wenchen Zheng, Hailong Hu, Tailiang Guo, Fushan Li
Summary: This study demonstrated the fabrication of a highly ordered QD monolayer with the LB technique, which significantly improved the performance and lifetime of QLEDs. The LB-HL strategy showed promising scalability for large-area QD monolayers.
SCIENCE CHINA-MATERIALS
(2022)
Article
Chemistry, Physical
S. Liu, R. Fan, Y. Zhao, M. Yu, L. Li, Q. Li, B. Liang, W. Zhang
Summary: In this study, a relatively less toxic CISSe quantum dot was prepared by an organic high-temperature hot injection method for use in QD-sensitized solar cells. Through Sn doping and ZnS passivation, the electron collection efficiency was improved and charge recombination was inhibited, resulting in a power conversion efficiency of 6.7% for the QDSSC.
MATERIALS TODAY ENERGY
(2021)
Article
Engineering, Electrical & Electronic
Zhijian Shen, Zhuo Deng, Xuyi Zhao, Jian Huang, Lu Yao, Xinbo Zou, Chunfang Cao, Qian Gong, Baile Chen
Summary: This article demonstrates the optical properties of a long-wave infrared InAs/GaAs sub-monolayer quantum dot quantum cascade photodetector grown on a GaAs substrate, showing its potential competitiveness in long-wave infrared imaging applications.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Review
Chemistry, Physical
Akash S. Rasal, Sudesh Yadav, Anil A. Kashale, Ali Altaee, Jia-Yaw Chang
Summary: This review discusses the factors influencing the performance stability of QDSSCs and provides insights into the mechanisms causing degraded performances. It also presents cutting-edge strategies for improving the overall performance stability of QDSSCs.
Article
Chemistry, Physical
Danwen Yao, Zhenyu Hu, Liansheng Zheng, Shanming Chen, Wei Lu, Huailiang Xu
Summary: The research focuses on the fabrication of CdS/CdSe-sensitized quantum dot sensitized solar cells (QDSSCs) using laser-engineered black rutile TiO2 nanoparticles (TiO2-NPs) as the photoanode material. The results show that the devices based on black TiO2-NPs have significantly higher power conversion efficiency (PCE) compared to those using pristine TiO2-NPs. Analysis of absorption and electrochemical impedance spectroscopy indicates that the device with the highest PCE has the highest absorption efficiency in a wide spectral range and the smallest series resistance, which can be attributed to the surface modification of TiO2-NPs by femtosecond laser pulses.
APPLIED SURFACE SCIENCE
(2023)
Article
Optics
Vojtech Miller, Karel Zidek
Summary: This paper presents a setup for high-precision transmission measurement of Ti:Sa crystals using Nd:YAG and Er:YAG lasers. By utilizing synchronous detection via a double integrated sphere, the transmission uncertainty of 0.01-0.03% and FoM precision of +/- 7.5% were achieved. Experimental results demonstrate that spatial inhomogeneities and angular mismatch can significantly affect the FoM values.
Article
Chemistry, Physical
Supriya Ghosh, Bapi Pradhan, Weihua Lin, Yiyue Zhang, Luca Leoncino, Pavel Chabera, Kaibo Zheng, Eduardo Solano, Johan Hofkens, Tonu Pullerits
Summary: In the past two decades, research has focused on suppressing Auger recombination in metal-chalcogenide and perovskite nanocrystals (PNCs) for photovoltaic and light emitting device (LED) applications. A study examined dodecahedron cesium lead bromide perovskite nanocrystals (DNCs) and found that they exhibit slower Auger recombination compared to hexahedron nanocrystals (HNCs). The research demonstrates that multiexciton recombinations result in lower Auger recombination rates in DNCs than in HNCs.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Optics
Jiri Junek, Karel Zidek
Summary: The RATS method is proven to be useful for measuring photoluminescence dynamics and fluorescence lifetime imaging. Two fundamental developments are presented: using random digital laser modulation for nanosecond-resolution measurement of photoluminescence dynamics, and using a single-pixel camera experiment for alternative evaluation of fluorescence lifetime imaging. These developments significantly save post-processing time and improve the accuracy stability of FLIM spectrogram.
Article
Energy & Fuels
Nannan Yao, Qunping Fan, Zewdneh Genene, Heng Liu, Yuxin Xia, Guanzhao Wen, Yusheng Yuan, Ellen Moons, Jan van Stam, Wei Zhang, Xinhui Lu, Ergang Wang, Fengling Zhang
Summary: This study investigates the device performance and morphology evolution of blade-coated all-polymer solar cells (all-PSCs) using PBDBT:PF5-Y5 blends prepared from two different solvents, chlorobenzene (CB) and ortho-xylene (o-XY). The results show that the CB-cast film has finer-mixed donor/acceptor nanostructures, leading to more efficient charge generation in the solar cells. The conformation of polymers in solution plays a crucial role in determining the overall film morphology and device performance.
Article
Optics
Marek Mach, Pavel Psota, Karel Zidek, Pavel Mokry
Summary: A compact lensless method based on digital holographic Fizeau interferometer is developed to image domain patterns in ferroelectric single crystals, providing a large field-of-view image with high spatial resolution. The method utilizes the electro-optic phenomenon to display the domain patterns in the crystal and measure the difference in the index of refraction.
Article
Chemistry, Physical
Albin Hedse, Alex Arash Sand Kalaee, Andreas Wacker, Tonu Pullerits
Summary: The double quantum coherence (DQC) signal in nonlinear spectroscopy provides information about many-body correlation effects that are difficult to obtain through other methods. Contrary to intuition, pulse overlap-related artifacts are not filtered out by the Fourier transform. Careful analysis of experiments is necessary to account for the pulse-overlap artifact.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Daniel Finkelstein-Shapiro, Pierre-Adrien Mante, Sinan Balci, Donatas Zigmantas, Tonu Pullerits
Summary: In polaritons, the properties of matter are modified by mixing molecular transitions with light modes, leading to hybrid light-matter states and modified exciton dynamics. This article rigorously derives non-Hermitian Hamiltonians in the response function formalism of nonlinear spectroscopy and explores spectroscopic signatures of plexcitons. The study reveals interference and Rabi splitting in linear spectroscopy and a qualitative change in the symmetry of the line shape of the nonlinear signal when crossing the exceptional point.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Xinyue Wang, Hongxiang Wang, Meixia Zhang, Tonu Pullerits, Peng Song
Summary: By studying the photoinduced electron transfer properties of the D-D-A molecule ((TPA-TT)-BODIPY-C60) in an external electric field (Fext), the excited-state properties of the molecule and the charge-transfer processes were investigated. The electronic coupling (VDA), reorganization energy (lambda), and free energy (Delta G) were calculated and simulated. It was found that exciton dissociation occurs in the Marcus inverted region and the charge-transfer rate is influenced by the changes in VDA and Delta G. The results provide a method for the design of a new type of electron transfer process with high efficiency in the D-D-A system.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Yanmei He, Siping Liu, Zehan Yao, Qian Zhao, Pavel Chabera, Kaibo Zheng, Bin Yang, Tonu Pullerits, Junsheng Chen
Summary: Low-dimensional perovskite-inspired materials with self-trapped exciton (STE) emission have sparked cutting-edge research in optoelectronics. However, there has been little focus on the intrinsic dynamics of broad emission based on STE in these materials. In this study, through femtosecond transient absorption spectroscopy, we directly observed the ultrafast process of STE formation in Cs2ZrCl6 nanocrystals, and obtained the dynamic rules of ultrafast STE formation. The formed STEs relax to an intermediate STE state with a lifetime of approximately 180 ps before reaching the emissive STE state with a lifetime of about 15 μs. Our work provides a comprehensive and precise dynamic picture of STE emission in low-dimensional metal halides and sheds light on expanding their potential applications.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Nils W. Rosemann, Linnea Lindh, Iria Bolano Losada, Simon Kaufhold, Om Prakash, Aleksandra Ilic, Jesper Schwarz, Kenneth Waernmark, Pavel Chabera, Arkady Yartsev, Petter Persson
Summary: Steady state and ultrafast spectroscopy were used to study [Fe-III(phtmeimb)(2)]PF6 over a broad range of temperatures. The intramolecular deactivation dynamics of the luminescent doublet ligand-to-metal charge-transfer ((LMCT)-L-2) state were analyzed, revealing the direct deactivation of the (LMCT)-L-2 state as a key limitation to its lifetime. Photoinduced disproportionation and subsequent bimolecular recombination of Fe(iv) and Fe(ii) complex pairs were observed in selected solvent environments. The efficient photoinduced intermolecular charge separation over a wide temperature range highlights the potential of [Fe-III(phtmeimb)(2)]PF6 for photocatalytic bimolecular reactions.
Article
Chemistry, Physical
Linnea Lindh, Torbjorn Pascher, Samuel Persson, Yogesh Goriya, Kenneth Warnmark, Jens Uhlig, Pavel Chabera, Petter Persson, Arkady Yartsev
Summary: The excited state dynamics of three iron(II) carbene complexes were investigated, revealing differences in dynamics between the complexes and the metal-centered triplet states. The study provides insights into the deactivation processes of the complexes and improves understanding of the photophysical limitations and opportunities for the use of iron(II) based photosensitizers in photochemical applications.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
