Article
Energy & Fuels
Jelby George, Alex P. Joseph, Manoj Balachandran
Summary: The emerging perovskite solar cells, rapidly advancing photovoltaic technology, have great future potential, despite facing challenges like stability and lead toxicity. This review provides an overview of the materials and functions of different layers of perovskite solar cells, discussing the evolution and performance of various solar cell materials qualitatively and quantitatively, highlighting the milestone towards the commercialization of environmentally friendly, economically feasible, and efficient solar cell materials.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2022)
Article
Materials Science, Multidisciplinary
Ahmal Jawad Zafar, Aranyo Mitra, Vadym Apalkov
Summary: In this study, the electron dynamics of a graphene nanoring in the presence of an ultrashort optical pulse were theoretically investigated. It was found that circularly polarized pulses can induce valley polarization in the graphene nanoring, whereas no valley polarization is observed in a graphene monolayer. The magnitude of the valley polarization in the graphene nanoring depends on the system parameters.
Article
Nanoscience & Nanotechnology
S. Lim, J. Kim, J. Y. Park, J. Min, S. Yun, T. Park, Y. Kim, J. Choi
Summary: Chloride-passivated SnO2 quantum dots were found to effectively suppress the cubic-phase degradation of CsPbI3 perovskite quantum dots, leading to improved device stability and power conversion efficiency in solar cells.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Physical
G. Nagaraj, Mustafa K. A. Mohammed, Masoud Shekargoftar, P. Sasikumar, P. Sakthivel, G. Ravi, M. Dehghanipour, Seckin Akin, Ahmed Esmail Shalan
Summary: This study introduces a method of using graphene quantum dots to modify the SnO2/ZnO layer to enhance the performance of perovskite solar cells, significantly improving opto-electronic properties and increasing power conversion efficiency. Devices with the modified electron transport layer show higher open-circuit voltage and long-term stability.
MATERIALS TODAY ENERGY
(2021)
Article
Chemistry, Physical
Pieter Schiettecatte, Zeger Hens, Pieter Geiregat
Summary: Atomically thin two-dimensional (2D) semiconductors are important for optoelectronic applications, but the nonlinear optical response is masked by congested spectral information. In this paper, a roadmap for analyzing congested datasets of various 2D materials using transient absorption (TA) is outlined, emphasizing the synergy between qualitative understanding of the transient photo-response and quantitative spectral deconvolution.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Alvaro J. Magdaleno, Mercy M. Cutler, Jesse J. Suurmond, Marc Melendez, Rafael Delgado-Buscalioni, Michael Seitz, Ferry Prins
Summary: Transient Photoluminescence Microscopy (TPLM) with cylindrical lenses allows for an improved visualization of carrier transport in semiconductor materials, with higher spatial resolution and collection efficiency.
Article
Chemistry, Multidisciplinary
Guili Li, Xiaoxian Zhang, Yongsheng Wang, Zhiying Bai, Hui Zhao, Jiaqi He, Dawei He
Summary: This study investigates the photocarrier dynamics in PdSe2 and reveals a photocarrier lifetime of around 210 ps, a diffusion coefficient of about 7.3 cm(2) s(-1), a diffusion length of approximately 400 nm, and a photocarrier mobility of around 300 cm(2) V-1 s(-1). These findings are crucial for understanding the ultrafast optoelectronic properties of PdSe2 and for designing high-performance optoelectronic devices based on this material.
Article
Chemistry, Multidisciplinary
Guili Li, Xiaoxian Zhang, Yongsheng Wang, Zhiying Bai, Hui Zhao, Jiaqi He, Dawei He
Summary: We investigated the behavior of photocarriers in bulk PdSe2 flakes using femtosecond transient absorption microscopy. Our findings show that the lifetime of photocarriers in bulk PdSe2 is approximately 210 ps, and the photocarrier diffusion coefficient is about 7.3 cm(2) s(-1). Based on these results, we estimate a diffusion length of around 400 nm and a photocarrier mobility of approximately 300 cm(2) V-1 s(-1). These results provide insights into the optoelectronic properties of PdSe2 and enable the design of high-performance optoelectronic devices.
Article
Chemistry, Multidisciplinary
Qirui Liu, Ke Wei, Yuxiang Tang, Zhongjie Xu, Xiang'ai Cheng, Tian Jiang
Summary: The excited-state dynamics in layered tungsten disulfide (WS2) were studied using transient absorption microscopy, which revealed the ultrafast hot carrier expansion and its potential in improving carrier harvesting. A cascaded transport model was proposed to explain the carrier diffusion mechanism in this system.
Article
Green & Sustainable Science & Technology
Savisha Mahalingam, Abreeza Manap, Azimah Omar, Foo Wah Low, N. F. Afandi, Chin Hua Chia, Nasrudin Abd Rahim
Summary: Graphene quantum dots (GQDs) with outstanding properties can be chemically modified and functionalized for high-performance dye-sensitized solar cells. Optimizing electron transport and electrolyte can further enhance the efficiency of GQD-DSSC.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2021)
Article
Chemistry, Multidisciplinary
Tao Li, Bin Li, Haoxiang Zhou, Jun Wang, Gang Ni, Wanli Ma, Chuanxiang Sheng, Jianyu Yuan, Haibin Zhao
Summary: This study reports on the ultrafast dynamics of charge transfer and exciton dissociation in single-material organic solar cells for the first time. It is found that the intramolecular interface in the block copolymer has a higher transfer rate, and the dilute PBDB-T-b-PTY6 film has faster exciton dissociation. By optimizing ordering, the power conversion efficiency of organic solar cells can be improved.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Materials Science, Ceramics
Chaoqun Lu, Weijia Zhang, Zhaoyi Jiang, Yulong Zhang, Cong Ni
Summary: Introducing graphene quantum dots into SnO2 improved film morphology, reduced surface roughness, and increased efficiency of perovskite photovoltaic devices.
CERAMICS INTERNATIONAL
(2021)
Article
Chemistry, Multidisciplinary
Jung-Yao Chen, Dong-Lin Yang, Fu-Cheng Jhuang, Yu-Han Fang, Jean-Sebastien Benas, Fang-Cheng Liang, Chi-Ching Kuo
Summary: Emulation of photonic synapses through photo-recordable devices has attracted attention for their low energy consumption and high parallelism in artificial neuromorphic networks. This study explored the impact of perovskite quantum dots on the photoresponsive characteristics of photomemory, demonstrating that quantum dots with the lowest valence band maximum and longest exciton lifetime show superior performance in terms of responsiveness and current ratios.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Optics
Dong Li, Xiaoxiao He, Litao Zhao, Haoyang Li, Yu Zhao, Sanjun Zhang, Xiaolei Zhang, Jinquan Chen, Qingyuan Jin, Jianhua Xu
Summary: By connecting positively charged cysteamine-coated ZnSe quantum dots with either negatively charged graphene oxide or reduced graphene oxide, ZnSe-GO and ZnSe-RGO composite materials are assembled. The study shows that the interaction between graphene oxide/reduced graphene oxide and ZnSe quantum dots can quench the exciton fluorescence of ZnSe quantum dots. Ultrafast electron transfer and energy level change are observed, which have potential applications in ZnSe-RGO composite materials.
JOURNAL OF LUMINESCENCE
(2022)
Article
Nanoscience & Nanotechnology
Nagarjuna Naik Mude, Yeasin Khan, Truong Thi Thuy, Bright Walker, Jang Hyuk Kwon
Summary: This study reports the development of high-efficiency and long-lifetime inverted green cadmium-free quantum dot light-emitting diodes (QLEDs) using a stable ZnO/ZnS cascaded electron transport layer (ETL). The use of ZnO/ZnS cascaded ETL allows for reduced electron injection, improving charge balance and suppressing exciton quenching in the QD layer. The optimized devices achieved significantly improved efficiency and long lifetime compared to reference devices.
ACS APPLIED MATERIALS & INTERFACES
(2022)
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
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
Nanoscience & Nanotechnology
Jie Meng, Qian Zhao, Weihua Lin, Tonu Pullerits, Kaibo Zheng
Summary: This study demonstrates the biexciton dynamics of core/shell quantum dots with submonolayer shell coverage. The results show that these quantum dots have a prolonged Auger lifetime. However, unlike conventional quantum dots, the dependence of the Auger recombination time on quantum dot size features two constant stages. This study provides a reference for the application of core-shell quantum dots in optoelectronic devices.
ADVANCED ELECTRONIC MATERIALS
(2023)
Article
Chemistry, Physical
Qi Shi, Pushpendra Kumar, Tonu Pullerits
Summary: We propose a temperature-dependent intensity modulated two-photon excited fluorescence microscopy technique for mapping charge carrier dynamics in perovskite microcrystal film. By analyzing the emission in harmonics of the excitation modulation frequency, we can study charge carrier recombination processes and potential accumulation effects. Our method allows for a quantitative comparison of different emission channels at a micrometer resolution. We applied this technique to a methylammonium lead bromide perovskite microcrystal film and investigated temperature-dependent modulated imaging, including exciton dissociation, charge carrier trapping-detrapping equilibrium, and phase transition at low temperatures.
ACS PHYSICAL CHEMISTRY AU
(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)
