Article
Chemistry, Physical
Nina Girotto, Fabio Caruso, Dino Novko
Summary: This study combines ab initio time-dependent Boltzmann equations and many-body phonon self-energy calculations to investigate the nonadiabatic phonon renormalization process in the MoS2 monolayer under nonequilibrium conditions. The results show that the nonequilibrium state of photoexcited MoS2 is influenced by the multi-valley topology of valence and conduction bands, leading to anisotropic electron-phonon thermalization paths and phonon renormalization around high-symmetry points. This work provides potential guidelines for controlling electron-phonon relaxation channels and phonon dynamics under extreme photoexcited conditions.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Mazhar Chebl, Xing He, Ding-Shyue Yang
Summary: This study reveals that black phosphorus undergoes interlayer lattice contraction and internal vibrations after photo injection and carrier relaxation, showing unique atomic motions that have important implications for single and few-layer black phosphorus and other vdW materials with strong electronic-lattice correlations.
Article
Materials Science, Multidisciplinary
H. Beyer, P. Hein, K. Rossnagel, M. Bauer
Summary: Time- and angle-resolved photoelectron spectroscopy was used to investigate the thermalization process of nonequilibrium carrier distribution in the Dirac cone of graphite after absorbing linearly polarized near-infrared laser pulses. The results showed a decay time constant of (20 +/- 3) fs for the photoinduced momentum anisotropy in the initial carrier population. The spectral peak of the initial carriers also exhibited an energy downshift of -100 meV within the first 30 fs, which was attributed to the emission of strongly coupled A'1 optical phonons at K. A fully thermalized distribution was established on a characteristic timescale of (40 +/- 10) fs. These findings highlight the complexity of carrier thermalization on ultrafast timescales, which result from the interplay between carrier-carrier and carrier-phonon interactions.
Article
Optics
Meng Deng, Zichun Liao, Yankai Chen, Ningning Yang, Xu Yan, Chi Zhang, Nengli Dai, Yi Wang
Summary: This paper demonstrates an ultrafast pulse laser based on a graphene pad on top of a silicon waveguide, achieving reduced pulse energy and pulse locking, laying the foundation for a new class of nonlinear devices. The carrier relaxation process in graphene/silicon structures is found to be three orders of magnitude faster than silicon, contributing to pulse narrowing.
PHOTONICS RESEARCH
(2021)
Article
Chemistry, Multidisciplinary
Saurabh K. K. Saini, Naveen Kumar Tailor, Prince Sharma, Lavi Tyagi, Nikita Vashistha, Rimjhim Yadav, Amit Kumar Chaudhary, Soumitra Satapathi, Mahesh Kumar
Summary: The research investigates the charge carrier and phonon dynamics in Bi2Se3 grown on various substrates. The orientation, size, and misfit of the substrate affect the dynamics. The heterointerface interactions of the different samples affect the vibration modes and acoustic phonon oscillations in Bi2Se3. The surface and bulk-bound charge carriers determine the frequency and velocity of the generated sound.
ADVANCED MATERIALS INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Yocefu Hattori, Jie Meng, Kaibo Zheng, Ageo Meier de Andrade, Jolla Kullgren, Peter Broqvist, Peter Nordlander, Jacinto Sa
Summary: By adjusting the operating temperature, the hot electron generation and transfer in plasmonic semiconductor materials can be optimized, contrasting with photodriven processes in nonplasmonic systems. This effect appears to be related to an enhancement in hot carrier generation due to phonon coupling. This discovery provides a new strategy for the optimization of photodriven energy production and chemical synthesis.
Article
Chemistry, Physical
Ivan Grigioni, Annalisa Polo, Maria Vittoria Dozzi, Lucia Ganzer, Benedetto Bozzini, Giulio Cerullo, Elena Selli
Summary: CuWO4 is a ternary metal oxide semiconductor with promising properties for photoelectrochemical water splitting and solar light conversion due to its low band gap and high stability. However, its relatively low PEC efficiency is attributed to the fast recombination dynamics of charge carriers photogenerated in CuWO4, which is discussed in relation to its PEC performance and compared with other semiconductor oxides, notably Fe2O3.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Multidisciplinary
Masatoshi Kimura, Xinyi He, Takayoshi Katase, Terumasa Tadano, Jan M. Tomczak, Makoto Minohara, Ryotaro Aso, Hideto Yoshida, Keisuke Ide, Shigenori Ueda, Hidenori Hiramatsu, Hiroshi Kumigashira, Hideo Hosono, Toshio Kamiya
Summary: A large enhancement in thermopower (S) is observed in thin films of LaNiO3 due to heterostructuring, with a 10 times enhancement over the bulk value. This enhancement is attributed to phonon drag effect and enhanced electron-phonon interaction, showing potential for high-performance thermoelectrics in transition-metal oxide heterostructures.
Article
Chemistry, Multidisciplinary
Jingang Li, Rundi Yang, Yoonsoo Rho, Penghong Ci, Matthew Eliceiri, Hee K. Park, Junqiao Wu, Costas P. Grigoropoulos
Summary: The distribution and dynamics of carriers in semiconductor materials play a crucial role in their physical properties and performance in industrial applications. As electronic and photonic devices continue to shrink in size, there is a need for tools to study carrier behavior at picosecond time and nanometer length scales. In this study, we present pump-probe optical nanoscopy to investigate carrier dynamics in silicon nanostructures. By combining experiments with the point-dipole model, we are able to determine the size-dependent lifetime of photoexcited carriers in individual silicon nanowires. Additionally, we demonstrate the mapping of local carrier decay time in silicon nanostructures with sub-50 nm spatial resolution. This study enables the nanoimaging of ultrafast carrier kinetics and has promising applications in the design of various electronic, photonic, and optoelectronic devices.
Article
Physics, Applied
Saulius Marcinkevicius, James S. Speck
Summary: Femtosecond pump-probe experiments were conducted on Sn-doped n-type beta-Ga2O3 in a transmission geometry, revealing the dynamics of free electrons and electron-phonon scattering processes involving polar optical and intervalley phonons. The obtained results provided insights into the scattering times and energy differences between conduction band minima.
APPLIED PHYSICS LETTERS
(2021)
Article
Physics, Applied
Wentao Qiu, Weizheng Liang, Jia Guo, Limei Fang, Ning Li, Qingguo Feng, S. N. Luo
Summary: The study reveals that the hot carrier dynamics of PtSe2 are significantly dependent on its thickness, with different processes contributing to carrier decay in semiconducting and metallic PtSe2 films. In semiconducting films, electron-phonon coupling, interlayer charge transfer, and nonradiative recombination are involved, while in metallic films, electron-phonon coupling dominates the carrier decay.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Chemistry, Multidisciplinary
Jianbo Hu, Yang Xiang, Beatrice Matilde Ferrari, Emilio Scalise, Giovanni Maria Vanacore
Summary: Transition metal dichalcogenides layered nano-crystals show great potential as next-generation optoelectronic and quantum devices. Understanding the interaction between excitonic states and atomic vibrations is crucial for their fundamental properties. This study investigates the structural dynamics of low-energy indirect excitons in MoS2 following nearly-resonant excitation using ultrafast electron diffraction and ab initio calculations. The results reveal the specific phononic excitations associated with the wavelength-dependent electronic transitions of the system, highlighting their strong selectivity.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Physical
Alexander J. Auty, Negar Mansouriboroujeni, Thiba Nagaraja, Dimitri Chekulaev, Christopher M. Sorensen, Suprem R. Das, Natalia Martsinovich, Adrien A. P. Chauvet
Summary: The electronic properties of inkjet-printed aerosol gel graphene (AG) films and inkjet-printed graphene (G) films were compared. AG films have a higher oxygen content and a complex 3D morphology compared to graphene. The similarity in the carrier-optical phonon scatter rates suggests a comparable lattice defect density between AG and G films. Interestingly, AG films exhibit lower recovery of the transient signal, indicating the presence of long-lived electronic states.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Physics, Applied
Bo Wang, Gaoshuai Wei, Jianing Chen, Li Wang
Summary: This study investigates ultrafast spin polarization in semi-insulating GaAs using terahertz time-domain spectroscopy. The results demonstrate that the transmitted and reflected terahertz signals exhibit different dynamic evolutions under the excitation of different polarization laser pulses, indicating the generation and relaxation process of spin-polarized electrons.
APPLIED PHYSICS LETTERS
(2022)
Article
Physics, Multidisciplinary
Jian Liu, Jing Li, Kai-Jun Mu, Xin-Wei Shi, Jun-Qiao Wang, Miao Mao, Shu Chen, Er-Jun Liang
Summary: In this study, the carrier dynamics of a Cu2O thin film prepared by radio-frequency magnetron sputtering under two-photon excitation was investigated using femtosecond transient absorption experiments. The results showed a biexponential dynamics with ultrafast carrier scattering (<1 ps) and carrier recombination (>50 ps). The time constant of carrier scattering under two-photon excitation was found to be larger than that under one-photon excitation.
Article
Biophysics
Luan Quang Le, Kaicheng Zhu, Haibin Su
Summary: Understanding prokaryotic cell growth requires a multiscale modeling framework that considers the kinetics pathway of ribosomes and the molecular responses to nutrient conditions. The competitive binding between cognate and near-cognate tRNAs for ribosomes can be modulated by [Mg2+]. A kinetics framework is developed to bridge ribosomal synthesis to cell growth, optimizing the cell growth rate by varying the characteristics of ribosomal synthesis through cellular responses to different nutrient conditions. Experimental measurements show quantitative agreement with two quadratic scaling relations: nutrient flux versus cell mass and ribosomal number versus growth rate.
BIOPHYSICAL JOURNAL
(2023)
Article
Chemistry, Inorganic & Nuclear
Ziao Wang, Yao Xu, Tao Feng, Chaojun Lei, Yu Zhao, Xi Zhu
Summary: Applying NLP to catalytic reaction journals, a gap between photocatalysts and thermal catalysts was found, leading to an investigation on THz catalysis. An excellent Ti3C2F2 MXene electrocatalyst that accelerates the catalytic process of HER and CO2RR is reported, with high selectivity towards the gaseous product CO observed in the CO2RR reaction. The THz catalysis is achieved through the resonance between CO2's vibrational mode and the surface phonon mode, as discussed in detailed computational studies. Potential future applications of MXene in THz catalysis are expected.
INORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Multidisciplinary
Bing Wang, Xi Zhu, Xudong Pei, Weigui Liu, Yecheng Leng, Xiwen Yu, Cheng Wang, Lianghe Hu, Qingmei Su, Congping Wu, Yingfang Yao, Zhiqun Lin, Zhigang Zou
Summary: Reported a one-step laser-planting strategy to craft single atoms of interest on various substrates under atmospheric conditions. The strategy involves the creation of defects on the substrate and the decomposition of precursors into monolithic metal single atoms, which are immobilized on the defects via electronic interactions. The strategy enables high defect density and achieves a record-high loading of single atoms.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Biochemistry & Molecular Biology
Kalok Chan, Long Thanh Ta, Yong Huang, Haibin Su, Zhenyang Lin
Summary: In this study, a simple molecular representation method was developed using machine learning and artificial intelligence techniques to predict rate constants of aryl bromides in palladium-catalyzed Sonogashira coupling reactions. The results demonstrate the importance of incorporating domain knowledge into machine learning for improved data analysis.
Article
Nanoscience & Nanotechnology
Elena Salagre, Pilar Segovia, Miguel Aïngel Gonzalez-Barrio, Matteo Jugovac, Paolo Moras, Igor Pis, Federica Bondino, Justin Pearson, Richmond Shiwei Wang, Ichiro Takeuchi, Elliot J. Fuller, Alec A. Talin, Arantzazu Mascaraque, Enrique G. Michel
Summary: We have developed a novel delithiation process for thin film lithium cobalt oxide cathodes. By using ion sputtering and annealing cycles, we can achieve delithiation without chemical byproducts and electrolyte interaction. This method allows for the identification of the effects of lithium extraction and provides detailed information on the role of oxygen and cobalt atoms in charge compensation.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
Yanheng Xu, Shuqian Ye, Xi Zhu
Summary: The past decade has seen extensive use of artificial intelligence (AI) and robotics in chemistry and material science. However, there is a lack of focus on idea generation, which is crucial for research novelty and breakthroughs. The exponential growth in scientific publications has led to overpublishing, making it difficult for researchers to keep up with multiple fields. To address these challenges, a deep learning-based AI supervisor trained on correlation-based ScholarNet data has been developed to recommend research ideas and assess their novelty, providing comprehensive guidance to researchers in material science.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Zhihang Guo, Junzi Li, Rulin Liu, Yang Yang, Changshun Wang, Xi Zhu, Tingchao He
Summary: Understanding the chiral mechanism in chiral hybrid perovskites is crucial for the development of chiroptoelectronic applications. By employing a spacer cation alloying strategy, we demonstrate second-harmonic-generation circular dichroism (CD) microarea imaging in chiral perovskite thin films, revealing their spatially correlated chirality. Our findings, combined with theoretical calculations, suggest that the spatially correlated chirality arises from localized out-of-plane supramolecular orientations.
Article
Chemistry, Physical
Hao Huang, Wenguang Tu, Liping Fang, Yelan Xiao, Feng Niu, Heng Zhu, Xi Zhu, Lu Wang, Yujie Xiong, Jianyong Feng, Huaiguang Li, Mingjian Zhang, Yongcai Zhang, Yingfang Yao, Yong Zhou, Hong Li, Zhigang Zou
Summary: Ammonia synthesis using the energy-intensive Haber-Bosch process contributes to global carbon emissions, but the photoelectrochemical (PEC) process utilizing solar energy offers a promising alternative with reduced carbon emission. However, the PEC process has limitations in terms of efficiency and rate of ammonia formation. In this study, a lithium-mediated PEC device is developed to efficiently reduce nitrogen into ammonia under ambient conditions, which provides a potential solar-driven catalytic system for ammonia synthesis.
ACS ENERGY LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Maximilian Mellin, Zhili Liang, Hadar Sclar, Sandipan Maiti, Igor Pis, Silvia Nappini, Elena Magnano, Federica Bondino, Ilargi Napal, Robert Winkler, Rene Hausbrand, Jan P. Hofmann, Lambert Alff, Boris Markovsky, Doron Aurbach, Wolfram Jaegermann, Gennady Cherkashinin
Summary: The thermal treatment of Li-rich cathodes with SO2 and NH3 gases improves capacity retention, rate capability, and voltage hysteresis in Li-ion batteries.
MATERIALS ADVANCES
(2023)
Article
Physics, Fluids & Plasmas
Kaicheng Zhu, Haibin Su
Summary: In this study, a new model is proposed to describe the nucleation-growth dynamics of individual nanocrystals by extending the free energy landscape to include activation-adsorption-relaxation reaction pathways. The crystallization dynamics were simulated using the Monte Carlo method based on the transition state theory. The results reveal a transient quasi-equilibrium stage before nucleation starts and a postnucleation crossover regime where the dynamic growth exponents asymptotically converge towards classical limits. Power laws are also generalized to address the dimension and scale effects for the growth of large crystals.
Article
Chemistry, Multidisciplinary
Alaa Mohammed Idris Bakhit, Khadiza Ali, Anna A. Makarova, Igor Pis, Federica Bondino, Roberto Sant, Saroj P. Dash, Rodrigo Castrillo-Bodero, Yuri Hasegawa, J. Enrique Ortega, Laura Fernandez, Frederik Schiller
Summary: This study investigates the structural, electronic, magnetic properties, and chemical stability of a reactive metal, Europium, intercalated between a hexagonal boron nitride (hBN) layer and a Pt substrate. It is found that the intercalation of Europium leads to the formation of a hBN-covered ferromagnetic EuPt2 surface alloy with divalent Eu2+ atoms at the interface. The system is exposed to ambient conditions, and partial conservation of the divalent signal is observed, indicating the stability of the Eu-Pt interface. By using a curved Pt substrate, the changes in the Eu valence state and the protection against ambient pressure at different substrate planes are explored. The formation of the interfacial EuPt2 surface alloy remains consistent, but the resistance of the protective hBN layer to ambient conditions is reduced, likely due to surface roughness and discontinuous hBN coating.
Article
Materials Science, Multidisciplinary
Cristian Soncini, Abhishek Kumar, Federica Bondino, Elena Magnano, Matija Stupar, Barbara Ressel, Giovanni De Ninno, Antonis Papadopoulos, Efthymis Serpetzoglou, Emmanuel Stratakis, Maddalena Pedio
Summary: In devices based on organic semiconductors, the aggregation and inter-molecular interactions significantly affect the photo-physical and dynamical carrier properties. Understanding the interplay between the molecular structure and material properties is crucial for designing devices with optimized performance. This study investigates how different molecular structural arrangements modulate the charge transfer dynamics in cobalt phthalocyanine thin films.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Chemistry, Physical
Kaicheng Zhu, Saber Naserifar, William A. Goddard, Haibin Su
Summary: In this work, detailed atomistic simulations were performed to investigate the dynamic properties of supercooled water. The analysis revealed multiscale features in the transient relaxation dynamics, with classical Langevin behavior dominating at fast timescales and two different activation barriers at long timescales. The modulation of the entropy spectrum by temperature was explained using a three-state model that involved a topological transition of the hydrogen-bond network. The quantitative characterization of the network topology provided valuable insights for further studies on the transient relaxation dynamics of supercooled water.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Jiaying Lin, Rulin Liu, Peixian Chen, Yangfei Lv, Junjie Hao, Meijuan Chen, Dongxiang Zhang, Ruikun Pan, Yiwen Li, Xi Zhu, Tingchao He, Jiaji Cheng
Summary: Stimulating and harnessing circularly polarized luminescence (CPL) is crucial for understanding chirogenesis in physical chemistry and implementing it in research fields such as chiral optoelectronics and theranostics. In this study, red-emissive carbonized polymer dots (CPDs) with enhanced circular dichroism (CD) and CPL activities were synthesized using a biomolecule-tailored organic-inorganic co-assembly strategy. The obtained CPL signals can be manipulated in an excitation-dependent manner, indicating a synergistic-competition phenomenon between configurational chirality and intermolecular energy-transfer dynamics.
Article
Chemistry, Multidisciplinary
Haoxiang Lin, Xi Zhu
Summary: The atomic-fragment approximation (AFA) uses the tensor network (TN) as a platform to estimate molecular properties by adding up fragment properties. The AFA framework utilizes graph neural networks to predict matrix product states (MPSs) for atoms and matrix product operators (MPOs) for bonds, which are then contracted to obtain the full TN for the molecule. AFA addresses the limitations of density functional approximation (DFA) and overcomes error accumulation by optimizing intermediate fragments.
