Article
Chemistry, Physical
Leandro Ramos Marques, Romulo Augusto Ando
Summary: FLP is formed by the collision of Lewis acid and base, and resonance Raman spectroscopy is used to probe the weak interaction involved.
Article
Nanoscience & Nanotechnology
Pedro H. M. Andrade, Hania Ahouari, Christophe Volkringer, Thierry Loiseau, Herve Vezin, Matthieu Hureau, Alain Moissette
Summary: This study focuses on the capture and transformation of gaseous I-2 using three distinct terephthalate-based MOFs: MIL-125(Ti), MIL-125(Ti)_NH2, and CAU-1(Al)_NH2. The results show that MIL-125(Ti)_NH2 exhibits the highest capture capacity, which is attributed to its amino group affinity, smaller band gap energy, and efficient charge separation.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Nanoscience & Nanotechnology
Monika Poonia, Timo Kuster, Geoffrey D. Bothun
Summary: Detecting ultralow concentrations of anionic analytes in solution remains challenging. This study investigated two strategies for in-situ, liquid phase detection using 5(6)-carboxyfluorescein (5(6)-FAM) as a model analyte: functionalization of a gold nanopillar substrate with cationic cysteamine self-assembled monolayer (CA-SAM) and electrokinetic preconcentration (EP-SERS). The results showed that detection was only possible with an applied electric field, which drove the charged molecules to the substrate surface, and the SERS intensity followed the Langmuir adsorption model.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Physical
Yumiao Dong, Qinhui Xie, Shuo Wu, Junbo Li, Lei Sun, Wei Ji
Summary: The adsorption mechanism of 4-MBA on TiO2 surfaces is found to be highly dependent on the exposure of acid sites, with preferential adsorption on Bronsted acid sites of a-TiO2 through a carboxyl group and on Lewis acid sites of c-TiO2 through a sulfhydryl group. Furthermore, 4-MBA molecules may form multilayer adsorption on TiO2 surfaces through hydrogen bonding and/or pi-pi stacking interactions. These findings provide new insights into the chemical enhancement mechanism for TiO2-4-MBA systems and offer theoretical guidance for the modification of TiO2 surfaces with organic molecules containing carboxyl and sulfhydryl groups.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Materials Science, Multidisciplinary
Wang-Hyo Kim, Joseph Mapley, Deok-Ho Roh, Jeong Soo Kim, So Yeon Yoon, Keith C. Gordon, Tae-Hyuk Kwon
Summary: The study revealed a potential relationship between the molecular structures of photosensitizers and their charge transfer (CT) properties. It was found that the presence of triple bonds and electron donating groups enhances the CT properties of the photosensitizer, impacting the performance of dye sensitized solar cells (DSSCs).
MATERIALS TODAY ADVANCES
(2021)
Article
Chemistry, Multidisciplinary
Piotr Kabacinski, Pietro Marabotti, Daniele Fazzi, Vasilis Petropoulos, Andrea Iudica, Patrick Serafini, Giulio Cerullo, Carlo S. S. Casari, Margherita Zavelani-Rossi
Summary: Investigated the photophysics of one-dimensional linear nanostructures and revealed their excellent mechanical, thermal, and electronic properties. Studied the excited state relaxation processes using experimental and computational methods, providing important insights into photoinduced events in low-dimensional carbon-based materials.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Spectroscopy
Elliot J. Tay, Jonathan E. Barnsley, Daniel B. Thomas, Keith C. Gordon
Summary: Resonance Raman spectroscopy was used to identify and characterize psittacofulvins, showing different behaviors in red and yellow regions with Raman band wavenumber shifts. One yellow region exhibited similar characteristics to the red regions, suggesting the presence of psittacofulvins with greater conjugation.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2021)
Article
Chemistry, Analytical
Jing Guo, Xingxu Yan, Mingjie Xu, Govinda Ghimire, Xiaoqing Pan, Jin He
Summary: An effective method has been developed to tune the intensity of surface-enhanced Raman scattering (SERS) of non-electroactive molecules by electrochemical means, involving the formation of nanostructures between Au@Ag core-shell nanoparticles and a gold nanoelectrode. The tuning is achieved by transforming the chemical composition of the thin Ag shell from metallic Ag to insulating AgCl, instead of introducing molecular changes by the electrode potential. The electrode potential can also tune the electromagnetic enhancement (EME) and specific Raman bands associated with Ag-molecule interaction in the Au@Ag nanostructures.
ANALYTICAL CHEMISTRY
(2021)
Article
Chemistry, Analytical
Ge Song, Hongzhao Sun, Jian Chen, Zhigang Chen, Boyang Liu, Zhenghui Liu, Shan Cong, Zhigang Zhao
Summary: There is great research interest in building semiconductor-based SERS platforms, and this study demonstrates the use of MoO3·xH2O quantum dots to achieve highly efficient SERS sensing of small inorganic molecules. The study highlights the crucial role of the quantum size effect in enhancing SERS activity in semiconductor-based materials.
ANALYTICAL CHEMISTRY
(2022)
Article
Chemistry, Analytical
Ge Song, Hongzhao Sun, Jian Chen, Zhigang Chen, Boyang Liu, Zhenghui Liu, Shan Cong, Zhigang Zhao
Summary: There is a strong research interest in constructing highly effective semiconductor-based SERS platforms, but current tuning methods have not been successful in creating sensors for small inorganic molecules. This study demonstrates the use of MoO3 middotxH2O quantum dots for sensitive detection of hydrazine and other probe molecules, utilizing the quantum size effect to enhance SERS activity.
ANALYTICAL CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Xingpin Li, Xiangyu Jia, Amiel S. P. Paz, Yuquan Cao, William J. Glover
Summary: This study used time-dependent density functional theory to simulate the X-ray absorption spectrum of the hydrated electron. A unique peak at 533 eV was observed, in agreement with recent experiments, and assigned to transitions from water O1s to the singly occupied molecular orbital (SOMO). The transitions acquired oscillator strength due to a mixing of a cavity-localized orbital and water antibonding orbitals.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Inorganic & Nuclear
Sanchaita Dey, Arijit Singha Hazari, Shaikh M. Mobin, Goutam Kumar Lahiri
Summary: In this study, a series of non-chelated BTD-bridged diruthenium(II) and triruthenium complexes were synthesized and characterized, and their properties in different coordination modes were studied. These complexes exhibited metal-based anisotropic electron paramagnetic resonance and intense low-energy intervalence charge-transfer transitions in the near-infrared region.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Physical
Sergii Golovynskyi, Oleksandr I. Datsenko, Dan Dong, Yan Lin, Iuliia Golovynska, Zijing Jin, Baikui Li, Honglei Wu
Summary: This study examines the photo-luminescence of 1L-QD/MoS2 hybrid and compares it to bare 1L MoS2. The results show that the PL intensity is significantly enhanced in the 1L-QD/MoS2 hybrid. This enhancement is attributed to nonradiative energy transfer and charge transfer processes.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Physical
Jie Yang, Gao Song, Ling Zhou, Xinyue Wang, Lijun You, Jumei Li
Summary: In this study, Ag/TiO2 core-shell nanoparticles were successfully synthesized for SERS detection of TMTD, showing a good linear relationship and low detection limit. The protective TiO2 shell enhances SERS signal by preserving SS bonds intact.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Takashi Fujita, Kohei Shibamoto
Summary: Uniform 2D arrays of metal nanoparticles can be formed using the sandwich technique, which is an important development in molecular sensing. The drying conditions during the formation process play a crucial role in obtaining a uniform and ideal array structure. These 2D arrays of metal nanoparticles exhibit excellent spot-to-spot reproducibility in surface-enhanced Raman scattering.
Article
Chemistry, Multidisciplinary
Yingya Yang, Florian Doettinger, Christian Kleeberg, Wolfgang Frey, Michael Karnahl, Stefanie Tschierlei
Summary: This study evaluates and compares two different design approaches to improve copper based photosensitizers. The findings show that one copper complex exhibits enhanced visible light absorption and solvent-dependent excited state lifetimes, as well as exceptional photostability.
FRONTIERS IN CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Jia-Wei Wang, Fan Ma, Tao Jin, Piao He, Zhi-Mei Luo, Stephan Kupfer, Michael Karnahl, Fengyi Zhao, Zihao Xu, Tao Jin, Tianquan Lian, Yong-Liang Huang, Long Jiang, Li-Zhi Fu, Gangfeng Ouyang, Xiao-Yi Yi
Summary: Exploiting noble-metal-free systems for efficient photocatalytic CO2 reduction remains challenging due to the difficulties in developing earth-abundant photosensitizers. This study focuses on a series of homoleptic Al(III) photosensitizers with 2-pyridylpyrrolide ligands for CO2 photoreduction using inexpensive aluminum metal. By introducing methyl groups at the pyrrolide rings, the visible-light absorption, reducing power, and durability of the Al(III) photosensitizers are greatly improved. The optimized system achieves a high quantum efficiency and CO2-to-CO conversion selectivity, making it a promising component in noble-metal-free systems for solar fuel conversion.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Parijat Barman, Abhik Chakraborty, Denis A. Akimov, Ankit Kumar Singh, Tobias Meyer-Zedler, Xiaofei Wu, Carsten Ronning, Michael Schmitt, Juergen Popp, Jer-Shing Huang
Summary: Plasmonic gratings with spatially resolved broadband momentum were used to investigate plasmonic enhancement effects in two nonlinear optical processes, TPPL and SHG. The experimental spatial distributions of nonlinear signals agreed well with analytical predictions, highlighting the antenna function of the grating in plasmonic nonlinear signal generation.
Article
Chemistry, Physical
Florian Doettinger, Martin Obermeier, Volkan Caliskanyuerek, Lars E. Burmeister, Christian Kleeberg, Michael Karnahl, Matthias Schwalbe, Stefanie Tschierlei
Summary: In this study, the structure-property relationship of heteroleptic Cu-I photosensitizers was investigated in detail. Two structurally closely related complexes were compared, and it was found that even small changes in the molecular structure can significantly affect their photophysical properties. The reasons for the superior photophysical properties of Cu2 were elucidated through a combination of various experimental and computational techniques. Furthermore, both complexes were tested for their activity in photocatalytic water splitting and CO2 reduction, and Cu2 outperformed Cu1, as well as the benchmark system and the noble-metal-based complex [Ir(dFppy)(3)].
Article
Chemistry, Inorganic & Nuclear
Florian Doettinger, Yingya Yang, Michael Karnahl, Stefanie Tschierlei
Summary: The merging of a pyrene moiety with a copper-(I) based photosensitizer has resulted in the development of superior bichromophoric systems. The precise position and type of substitution play a crucial role in determining the properties and photocatalytic activity. Through extensive studies, it has been shown that attaching pyrene via its 1-position and substituting the pyridine rings of phenanthroline in the 4,7-position with the 1-pyrenyl moiety have the strongest impact on the bichromophore, resulting in significant improvements in reduction potential, excited state lifetime, single oxygen quantum yield, and photocatalytic activity.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Thomas Gottschall, Tobias Meyer-Zedler, Matthias Eibl, Tom Pfeiffer, Hubertus Hakert, Michael Schmitt, Robert Huber, Andreas Tunnermann, Jens Limpert, Juergen Popp
Summary: Coherent Raman scattering microscopy utilizing bioorthogonal tagging approaches allows for targeted monitoring of small molecules in biological samples. To fully exploit this technique, a fast tunable laser is needed. The authors present a laser concept without moving parts for simultaneous acquisition of coherent anti-Stokes Raman scattering images at multiple Raman resonances.
JOURNAL OF PHYSICAL CHEMISTRY B
(2023)
Article
Biochemical Research Methods
Rola Houhou, Elsie Quansah, Tobias Meyer-zedler, Michael Schmitt, Franziska Hoffmann, Orlando Guntinas-lichius, Juergen Popp, Thomas Bocklitz
Summary: Biophotonic multimodal imaging techniques are used to study biological samples, but the measurement time increases significantly for high-resolution images. Mathematical methods and artificial intelligence (AI) based approaches were compared in this research to shorten the acquisition time and improve data quality. The AI methods included transfer learning using the pre-trained network DnCNN and training networks using augmented images. Deep learning techniques showed potential in improving image quality and reducing acquisition time. The proposed network had a simpler architecture compared to similar-performing but highly parametrized networks.
BIOMEDICAL OPTICS EXPRESS
(2023)
Article
Engineering, Biomedical
Justyna Anna Niestrawska, Marko Rodewald, Constanze Schultz, Elsie Quansah, Tobias Meyer-Zedler, Michael Schmitt, Juergen Popp, Igor Tomasec, Benjamin Ondruschka, Niels Hammer
Summary: This study examines the link between location-dependent mechanical anisotropy and principal collagen fiber orientation in the human dura mater. The quantitative observation of collagen fiber orientation and dispersion confirms that collagen is highly aligned in the dura mater and that both fiber orientation and dispersion differ depending on the location investigated. These findings provide insight into the previously observed isotropic mechanical behavior and have implications for the mechanical load response and regional functions of the dura mater.
ACTA BIOMATERIALIA
(2023)
Article
Chemistry, Multidisciplinary
David Hernandez-Castillo, Roland E. P. Nau, Marie-Ann Schmid, Stefanie Tschierlei, Sven Rau, Leticia Gonzalez
Summary: Understanding the factors that determine the luminescence lifetime of transition metal compounds is crucial for applications in photocatalysis and photodynamic therapy. This study challenges the commonly accepted idea that emission lifetimes can be controlled by optimizing the energy barrier or gap between different excited states. Instead, an extended kinetic model that considers all the pathways related to multiple isomers is found to accurately predict temperature-dependent emission lifetimes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Martin Obermeier, Volkan Caliskanyuerek, Rana Lomlu, Robin Giereth, Beatrice Cula, Stefanie Tschierlei, Matthias Schwalbe
Summary: This study reports the synthesis and characterization of two isomers of homobimetallic rhenium complexes and their photo- and electrochemical properties. The CO2 to CO transformation was observed in the presence of the photosensitizer [Ir(dFppy)(3)], showing enhanced catalytic activity due to the cooperative Re-Re interaction. Electrochemical measurements also demonstrated the cooperative CO2 activation for one of the isomers, cisL1-Re2Cl2. These isomers exhibit better catalytic properties compared to their mononuclear counterpart.
Article
Chemistry, Analytical
Edoardo Farnesi, Silvia Rinaldi, Chen Liu, Jonas Ballmaier, Orlando Guntinas-Lichius, Michael Schmitt, Dana Cialla-May, Juergen Popp
Summary: Saliva, as a body fluid, plays an important role in point-of-care medicine for real-time health monitoring and personalized preventative therapy. The combination of SERS and MD simulations can verify the traceability of specific biomarkers in saliva, opening up a new pathway for precision medicine diagnostics.
Article
Chemistry, Physical
Florian Doettinger, Christian Kleeberg, Clemence Queffelec, Stefanie Tschierlei, Yann Pellegrin, Michael Karnahl
Summary: This study focuses on heteroleptic copper(I) complexes, aiming to design efficient photocatalysts based on earth-abundant metals. Through synthesis and comparison, it is found that substituents at the 4 and 7-positions of the complexes result in better absorption properties compared to those at the 5 and 6-positions. The (trifluoromethyl)2 substituent plays a special role in enhancing the photocatalytic activity of the complexes.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Julian Hniopek, Josefine Meurer, Stefan Zechel, Michael Schmitt, Martin D. Hager, Juergen Popp
Summary: Stimuli-responsive polymers can switch specific physical properties in response to a change of the environmental conditions, making them useful for applications requiring adaptive materials. A straightforward method using Raman micro-spectroscopy and 2DCOS analysis is presented to study the response behavior of reversible polymers on a molecular level with molecular sensitivity and spatial as well as temporal resolution. This label-free and non-invasive approach allows for the investigation of macroscopic properties alongside the molecular response of the polymer to external stimuli.
