Article
Chemistry, Physical
Myrthe A. Bruning, Claus-Dieter Ohl, Alvaro Marin
Summary: When a pure droplet evaporates inside an elastic medium, two instabilities are typically observed: wrinkling and cavitation. The presence of colloidal particles can significantly alter these phenomena, triggering cavitation events and changing the order of instabilities. Research has shown that the size and concentration of colloidal particles play a crucial role in the early inception of cavitation in droplets within an elastic medium.
Article
Physics, Multidisciplinary
Yiming Xia, Xiunan Yang, Junchao Huang, Rui Liu, Ning Xu, Mingcheng Yang, Ke Chen
Summary: We constructed structural order parameters based on local angular and radial distribution functions in dense colloidal suspensions and found significant correlations between these parameters and local dynamics. In particular, the correlation between local orientational order and dynamical heterogeneity was consistently higher than the correlation between conventional two-body structural entropy and local dynamics. The structure-dynamics correlations can be explained by an excitation model where the energy barrier depends on local structural order. Our results suggest that in dense disordered packings, local orientational order is higher than translational order and plays a more important role in determining the dynamics in glassy systems.
PHYSICAL REVIEW LETTERS
(2023)
Article
Chemistry, Physical
Marjolein de Jager, Joris de Jong, Laura Filion
Summary: Computer simulations were used to study point defects in systems of soft colloidal particles, determining that the nature of lattice distortion is mainly determined by crystal structure. One-dimensional lattice distortions depend on dimensionality, with interstitial concentrations in BCC crystals reaching up to 1%.
Article
Multidisciplinary Sciences
Peng-Kai Kao, Bryan J. VanSaders, Sharon C. Glotzer, Michael J. Solomon
Summary: This research demonstrates that cyclically applied electric fields can improve the quality of colloidal crystals by annealing local disorder. The optimal off-duration for maximum annealing is found to be approximately half of the characteristic melting half lifetime of the crystalline phase. Local six-fold bond orientational order grows more rapidly than global scattering peaks, indicating that local restructuring leads to global annealing.
SCIENTIFIC REPORTS
(2021)
Article
Multidisciplinary Sciences
Qi Zhang, Wei Li, Kaiyao Qiao, Yilong Han
Summary: The nature of liquid-to-glass transition and glass-to-liquid transition is investigated in this study, especially focusing on the surface effects. Colloidal glasses are assembled by vapor deposition and melted by adjusting particle attractions. The results show the presence of a surface liquid layer and an intermediate glassy layer, and similar melting behaviors to crystal premelting and melting. Single-particle kinetics measurements confirm theoretical predictions for the glass surface layer.
Article
Energy & Fuels
Hamed Morshedian, Milad Abolhasani
Summary: The photostability of colloidal quantum dots (QDs) is crucial for their long-term applicability in energy and chemical technologies. However, current photostability studies are sensitive to experimental conditions, lack mechanistic understanding, and are time, material, and labor-intensive. In this study, an automated microfluidic platform is introduced for accelerated photostability studies of colloidal QDs, which is 3.5x faster and 100x more material efficient compared to conventional flask-based studies. The microfluidic strategy provides real-time access to the optical properties of QDs during the photostability experiments, shedding light on the complex and multifaceted photodegradation phenomena of colloidal QDs and demonstrating the unique advantages of microfluidic strategies for improving and accelerating QD photostability studies.
Article
Materials Science, Ceramics
Nikolai V. Priezjev
Summary: This study investigates the influence of static stress and alternating loading direction on the potential energy and mechanical properties of amorphous alloys using molecular dynamics simulations. It was found that at sufficiently large values of static stress, the binary glass becomes rejuvenated through collective, irreversible rearrangements of atoms. Including additional static stress orientation in the loading protocol amplifies the rejuvenation effect, leading to improvements in the mechanical properties of metallic glasses.
JOURNAL OF NON-CRYSTALLINE SOLIDS
(2021)
Article
Materials Science, Multidisciplinary
David Richard, Edan Lerner, Eran Bouchbinder
Summary: Understanding the fracture toughness of glasses is crucial for science and technology. Atomistic simulations show that varying parameters such as cooling rate and loading geometry can affect the toughness of glasses. Soft defects and loading geometry play significant roles in the toughness of glasses.
Article
Chemistry, Physical
Qi Li, Xiaoguang Peng, Dongjie Chen, Gregory B. McKenna
Summary: The study investigates the dynamics of a series of soft colloids with varying corona moduli, showing specific behaviors in concentration dependence. The use of a hard-soft mapping framework and extended theoretical models helps explain the properties and dynamics of soft colloids.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Mechanics
D. Parisi, D. Vlassopoulos, H. Kriegs, J. K. G. Dhont, K. Kang
Summary: Soft glasses of colloidal rods with orientational domains exhibit inhomogeneous flow profiles, including fracture, plug flow, and gradient shear-banding. The observed gradient shear-banding is mainly attributed to the strong shear thinning behavior of the material inside the domains. Both texture stress and domain-interior stress significantly contribute to the gradient shear-banding transition at high concentrations, while domain coalescence reduces texture stress at low concentrations.
JOURNAL OF RHEOLOGY
(2022)
Article
Chemistry, Multidisciplinary
Jorge Sanchez Llorens, Lorenzo Barbera, Ahmet F. Demirors, Andre R. Studart
Summary: A light-based printing platform is reported to shape colloidal glasses into 3D objects with complex geometries and vivid structural color. The photonic properties of the printed objects reflect the locally ordered microstructure of the glass. The platform demonstrates the capability to create 3D objects with isotropic structural color.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Physical
Atiya Badar, Mahesh S. Tirumkudulu
Summary: This study investigates the dynamics of cracks in colloidal coatings and derives an analytical solution. The study considers the stress and displacement fields near the crack tip under different crack speeds, taking into account factors such as particle volume fraction and mechanical properties. However, the predicted crack speeds are at least an order of magnitude higher than those observed in experiments, and further research is needed to explain this discrepancy.
Article
Polymer Science
Yuhui Yang, Quanyin Xu, Tiancheng Jin, Xinping Wang, Simone Napolitano, Biao Zuo
Summary: Deviations of chain conformations from Gaussian statistics induce entropic stress that affects the dynamics of polymer materials. Understanding its role is further complicated by the presence of enthalpic stresses, arising from the concurring change in bond energy and intermolecular interactions. By fabricating oriented poly(methyl methacrylate) brushes free from backbone deformation, the role of entropic stress on the nonisothermal relaxation of chains at both global and local levels was successfully identified. These results provide new insights into the dynamics and fundamental molecular mechanics of oriented, stressful polymer glasses, such as textile fibers.
Article
Polymer Science
Eduardo Guzman, Armando Maestro
Summary: This paper reviews the assembly of soft colloidal particles at fluid interfaces, focusing on the case of microgels formed by cross-linked polymer networks. The dual polymer/colloid character and stimulus responsiveness of microgel particles make their experimental characterization and theoretical description challenging. The dual nature of microgels controls the organization at fluid interfaces and the properties and responsiveness of the resulting microgel-laden interfaces.
Article
Chemistry, Physical
Xudong Yuan, Daniel Sopu, Kaikai Song, Juergen Eckert
Summary: Increasing free volume in metallic glasses rejuvenates them, but this free volume can be annihilated under deformation leading to structural relaxation and strain-hardening. Highly rejuvenated metallic glasses experience stress-driven structural and residual stress relaxation during cycling deformation, eventually reaching a more stable state but unable to recover their initial state.
