Article
Chemistry, Physical
Michael Zambrano-Angulo, Ricardo Pino-Rios, Eduardo Pino-Lopez, Gloria Cardenas-Jiron
Summary: The performance of lithium oxide (LO)-modified titanium dioxide (TiO2) as a photocatalyst was investigated using density functional theory (DFT). The results showed that the adsorption of LO influenced the electronic structure of TiO2, resulting in improved reactivity and decreased bandgap energy. The main absorption band also shifted towards visible light, indicating the potential of LO-TiO2 as a visible light-activated photocatalyst.
SURFACES AND INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Jingyun Ye, Donald G. Truhlar
Summary: This study compared seven choices of reference states for calculating equilibrium constants and transition state theory rate constants for flat surfaces, with some models being suitable for treating both mobile and localized adsorbates, while others are specific to localized or freely translating adsorbates. Models 6 and 7 were found to reduce computational costs by not requiring calculations of barrier heights for diffusion, and a simple ideal 2D hindered translator was noted for its physical high-temperature limit.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Thermodynamics
Xiang Wei, Chun-Mei Wu, You-Rong Li
Summary: The study thoroughly examines the influencing mechanisms of adsorption and cluster transition on interfacial heat transfer through molecular dynamics simulations. It reveals that the evolution and vibrational behavior of adsorption clusters play significant roles in the variation of interfacial thermal conductance. Different trends of thermal conductance are observed in two distinct regions during the adsorption process, with a rapid increase in region I and a slowing down of the changing rate in region II.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Chemistry, Physical
J. Puibasset, P. Judeinstein, J-M Zanotti
Summary: In this study, Monte Carlo simulations were used to investigate the metastable supercooled region of water, focusing on the isobaric specific heat capacity adsorbed on SiO2 surfaces. The results showed a qualitative agreement between simulated and experimental values at low temperatures.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
E. T. Jensen
Summary: The study found that methyl halides adsorbed on C6H6 and C6F6 display different photodissociation mechanisms, including neutral photodissociation and dissociative electron attachment pathways.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Taotao Ji, Yifan Song, Jiahui Yan, Yanwei Sun, Chen Wang, Sixing Chen, Yi Liu
Summary: Flawless coordination polymer (CP) glass films were successfully prepared using rapid hot casting and melt quenching techniques. The films exhibited excellent gas barrier properties and corrosion resistance due to the structure that inhibited the diffusion of guest molecules. This study demonstrates the high potential of CP glass films for applications in gas barrier layers and corrosion-resistant coatings.
CHEMISTRY OF MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Florian Malotke, Tobias Thiele, Jochen S. Gutmann, Michael Giese
Summary: A modular tool box for photoresponsive cholesteric liquid crystals based on hydrogen-bonded assemblies is developed, allowing tunable structural coloration. The blue shift in cholesteric liquid-crystalline thin films is attributed to the photoinduced destruction of smectic clusters, resulting in a contraction of the helical structure. Furthermore, the use of a stereolithography 3D printer enables the direct transfer of digital information into a multicolor photonic pattern.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
Xiaolin Zhou, Yufeng Zhou, Ya Deng, Yumin Zhang
Summary: The structure, vibrational density of states, and transport coefficients of liquid alumina were studied using molecular dynamics simulations, and the effects of temperature and density on the structure and properties were discussed.
Article
Chemistry, Physical
Yaoshen Ye, Kaixin Guo, Ruirui Cui, Min Zhang, Xu Wang, Majed A. Bajaber, Chaoyong Deng
Summary: The energy storage performance of BNT thin films was enhanced by introducing an amorphous alumina to construct AO-BNT heterojunctions, which significantly improved the breakdown strength and energy storage density.
SURFACES AND INTERFACES
(2022)
Article
Materials Science, Multidisciplinary
M. S. Tacca, T. Jacob, E. C. Goldberg
Summary: The study calculates the conductance spectra of a Co atom adsorbed on Cu(111) and finds that the interaction between atoms introduces a zero-bias anomaly, with the coupling with localized surface states playing a crucial role in shaping interference line profiles.
Article
Chemistry, Physical
A. M. Toikka, B. Gorovits, M. A. Toikka
Summary: Thermodynamic relationships are used to analyze phase diagrams of systems with chemical interaction near critical points. New variables are introduced to represent mole fractions. A general equation is derived for the isothermal-isobaric curve of chemical equilibrium in generalized concentration variables. Analysis of chemically reacting liquid-liquid systems near critical points is conducted and corresponding diagrams are presented.
RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Article
Materials Science, Multidisciplinary
Abdul Majid, Sunbul Zahid, Salah Ud-Din Khan, Ashfaq Ahmad, Shoukat Khan
Summary: The research focuses on addressing issues faced by DSSC by designing organic dye attached to (TM)FeO3/TiO2 structures using first principles methods. The structural and electronic properties of different structures are described, with stable cluster trends and reduced band gap of QD after adsorption.
MATERIALS SCIENCE AND ENGINEERING B-ADVANCED FUNCTIONAL SOLID-STATE MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Chan Shu, Maren Pink, Tobias Junghoefer, Elke Nadler, Suchada Rajca, Maria Benedetta Casu, Andrzej Rajca
Summary: This paper presents a quartet ground state triradical synthesized by a Pd(0)-catalyzed radicalradical cross-coupling reaction. The triradical has small doublet-quartet energy gaps, good thermal stability, and can form stable thin films on silicon substrate. These thin films show onset of decomposition after 4 hours under ambient conditions but have a longer lifetime than drop-cast films.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Energy & Fuels
Muhammad Iqbal Hussain, R. M. Arif Khalil, Fayyaz Hussain, Anwar Manzoor Rana
Summary: The study investigated the magnetic, electronic, and thermoelectric properties of RbTaO3 and FrTaO3 ternary perovskite oxide materials through advanced DFT method, revealing them to be semiconductors with unique band gap energy values. RbTaO3 showed superior thermoelectric parameters, suggesting it as a promising candidate for efficient thermoelectric devices.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2021)
Article
Materials Science, Coatings & Films
Yanhan Fang, Wenjie Sun, Lu Han, Zeya Li, Haoying Sun, Hongtao Yuan, Zhengbin Gu, Yuefeng Nie
Summary: The magnetic and electrical transport properties of doped manganites can be adjusted by controlling the concentration of oxygen vacancies. This study presents a method for the epitaxial growth of high quality La0.67Sr0.33MnO3-delta films with a large out-of-plane lattice parameter, achieved by using a Sr3Al2O6 buffer layer to stabilize the metastable phase.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2022)
Article
Materials Science, Composites
Tahereh Mohammadi Hafshejani, Chao Feng, Jonas Wohlgemuth, Felix Krause, Andreas Bogner, Frank Dehn, Peter Thissen
Summary: This study investigates the energy dissipation processes in cement-based materials under different stresses. The stretching and breakage of Si - O - Si and C - O bonds are found to be crucial. Increased molecular weight of PEG leads to stronger bonding between particles and the cement matrix, resulting in less energy absorption through other processes.
JOURNAL OF COMPOSITE MATERIALS
(2021)
Article
Multidisciplinary Sciences
Franziska Muckel, Severin Lorenz, Jiwoong Yang, Taufik Adi Nugraha, Emilio Scalise, Taeghwan Hyeon, Stefan Wippermann, Gerd Bacher
NATURE COMMUNICATIONS
(2020)
Article
Chemistry, Physical
Nils Schewe, Robin Wagner, Matthias Franzreb, Peter Thissen
Summary: The study investigates the adsorption of charged maleic acid on a graphene sheet, demonstrating that including a water layer significantly alters the conformation of charged adsorbed molecules and enhances the overall stability of the system. The experimental validation of the computational results shows good agreement with the study's findings.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Physics, Multidisciplinary
F. Deissenbeck, C. Freysoldt, M. Todorova, J. Neugebauer, S. Wippermann
Summary: Our novel approach samples the canonical ensemble at constant temperature and applied electric potential, easily implemented in any density-functional theory code. Using thermopotentiostat molecular dynamics simulations, we can calculate the dielectric constant of nanoconfined water without assumptions for dielectric volume. Compared to traditional methods, our technique reduces computational time significantly.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Physical
Tahereh Mohammadi Hafshejani, Jonas Wohlgemuth, Peter Thissen
Summary: Strain affects the surface reactivity of H-Si(111) by weakening Si-H bonds and causing intensity fluctuations in bending modes, leading to the formation of a new peak associated with the diffusion of hydrogen atoms. The findings suggest that both back bonds and up bonds are easily oxidized under strain, with the direct formation of Si-OH without an energy barrier. Different oxidation pathways predominate when strain is present.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Multidisciplinary
Mohammadreza Izadifar, Jorge S. Dolado, Peter Thissen, Andres Ayuela
Summary: Research on using reduced graphene oxide (rGO) in cementitious materials was conducted, with density functional theory used to study the binding between moieties on the rGO surface and CSH units. Simulations showed complex interactions between OH/rGO and silicate tetrahedra, while rGO/CSH interactions remained close to initial structural models. The study fills a gap in knowledge by establishing a connection between the chemical compositions of CSH units and rGO, and confirms the potential for using a wet chemical method to produce pristine graphene.
Article
Chemistry, Physical
Mohammadreza Izadifar, Carsten Natzeck, Katja Emmerich, Peter G. Weidler, Soheil Gohari, Colin Burvill, Peter Thissen
Summary: In this study, it was found that CO gas reacts with hydrated cement paste to form carbonate, driven by the dissociation of crystal water. Heating the system leads to the emission of CO2 instead of CO.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Hannes Boeckmann, Jan Gerrit Horstmann, Abdus Samad Razzaq, Stefan Wippermann, Claus Ropers
Summary: Exploiting vibrational excitation for dynamic control of material properties has wide-ranging technological potential. This study demonstrates mode-selective control over the metal-to-insulator phase transition in indium wires, enabling navigation of collective atomic motion within the potential energy surface. Exciton-phonon interactions allow for dynamic control of materials functionality.
STRUCTURAL DYNAMICS-US
(2022)
Article
Chemistry, Physical
Florian Deissenbeck, Stefan Wippermann
Summary: We discuss the incorporation of our recently proposed thermopotentiostat technique into existing ab initio molecular dynamics (AIMD) packages. By using thermopotentiostat AIMD simulations in the canonical NVT phi ensemble at a constant electrode potential, we calculate the polarization bound charge and dielectric response of interfacial water from first principles.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2023)
Article
Nanoscience & Nanotechnology
Thomas Schwartz, Nils Schewe, Matthias Schwotzer, Marita Heinle, Ammar Mahmood, Peter Krolla, Peter Thissen
Summary: Under environmental conditions, the incorporation of copper through metal exchange can enhance the resistance of surfaces to biofilm formation. Experimental results showed that the incorporation of copper into Ca(OH)2 solution can reduce bacterial colonization on modified surfaces and promote cluster formation.
ACS APPLIED BIO MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Jakob Moebs, Gina Stuhrmann, Stefan Wippermann, Johanna Heine
Summary: Lead-free heavy halogenido metalates are being intensively investigated due to their promising semiconducting properties. In this study, we present two isostructural iodido pentelates (Hpyz)(3)E2I9·2H2O (pyz=pyrazine; E=Sb, Bi), which exhibit stable properties up to 100°C. Surprisingly, the antimony compound has a smaller band gap size of 1.91 eV, while the bismuth compound has a slightly larger band gap size of 1.98 eV compared to similar pairs of compounds. DFT calculations confirm that the presence of charge transfer excitations contributes to this finding.
Article
Chemistry, Multidisciplinary
Tahereh Mohammadi Hafshejani, Ammar Mahmood, Jonas Wohlgemuth, Meike Koenig, Roberto C. Longo, Peter Thissen
Summary: Understanding the changes in micro-mechanical properties of semiconductor materials is crucial for designing new flexible electronic devices and controlling material properties. This study presents a novel tensile-testing device coupled with FTIR measurements for in situ atomic investigations of samples under uniaxial tensile load. The device allows mechanical studies of rectangular samples and reveals interesting fracture mechanisms and differences in interface properties under stress. Density functional theory calculations were also conducted to unravel differences in optic and electronic properties of interfaces with and without stress.
Article
Chemistry, Multidisciplinary
Peter Thissen, Jonas Wohlgemuth, Peter Weidler, Detlef Smilgies, Lars Heinke, Nils Schewe, Meike Koenig, Peter Krolla, Christof Woell
Summary: The properties of metal-organic frameworks (MOFs) are highly influenced by defect concentrations. A method has been developed to grow MOFs epitaxially on cm-sized Si(111) single crystals, resulting in nearly perfect structure with low defect density. Synchrotron-based grazing incidence X-ray diffraction (GI-XRD) experiments confirmed the high registry between crystalline metal-organic thin films and the substrate. The reduction of MOF defect density has significant effects on the properties of these porous frameworks, particularly in mass transport where a 10-fold increase in diffusion coefficient of guest molecules is observed.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Physical
Tahereh Mohammadi Hafshejani, Weijia Wang, Jonas Heggemann, Alexei Nefedov, Stefan Heissler, Yuemin Wang, Philipp Rahe, Peter Thissen, Christof Woell
Summary: Detailed information on the structural, chemical, and physical properties of natural cleaved (10.4) calcite surfaces was obtained through a combined AFM and IR study using CO as a probe molecule under UHV conditions. The study revealed the adsorption characteristics and vibrational frequencies of CO on the surface, with a well-defined adsorption site and clear vibrational bands.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Engineering, Electrical & Electronic
Roberto C. Longo, Nils Schewe, Peter G. Weidler, Stefan Heissler, Peter Thissen
Summary: The demand for different materials in the semiconductor field has driven strong research in the past decades, with atomic scale precision achieved for desired material properties through crystal doping. However, potential channel replacement materials for silicon like GaAs face safety and environmental concerns, prompting the search for non-toxic and environmentally friendly alternatives.
ACS APPLIED ELECTRONIC MATERIALS
(2021)
