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The dispersion of solid nanoparticles within polymeric materials is widely used to enhance their performance. Many scientific and technological aspects of the resulting polymer nanocomposites have been studied, but the role of the structural and chemical heterogeneity of the nanoparticles has just started to be appreciated. For example, simulations of polymer films on planar heterogeneous surfaces revealed unexpected, non-monotonic activation energy to diffusion on varying the surface composition. Motivated by these intriguing results, here we simulate via molecular dynamics a different, fully three-dimensional system, in which the heterogeneous nanoparticles are incorporated in a polymer melt. The nanoparticles are roughly spherical assemblies of strongly and weakly attractive sites, in fractions of f and 1 - f, respectively. We show that the polymer diffusion is still characterized by a non-monotonic dependence of the activation energy on f. The comparison with the case of homogeneous nanoparticles clarifies that the effect of the heterogeneity increases on approaching the polymer glass transition.
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http://dx.doi.org/10.1039/c7sm02414b | DOI Listing |
Langmuir
September 2025
Product & Process Engineering, Department of Chemical Engineering, Faculty of Applied Sciences, Delft University of Technology, 2629 HZ Delft, The Netherlands.
Noble metal nanoparticles (NPs), particularly platinum (Pt), are widely used in heterogeneous catalysis due to their exceptional activity. However, controlling their size and preventing sintering during synthesis remains a major challenge, especially when aiming for high dispersion and stability on supports such as graphene. Atomic layer deposition (ALD) has emerged as a promising method to address these issues, yet conventional processes often lead to broad particle size distributions (PSDs).
View Article and Find Full Text PDFAdv Sci (Weinh)
September 2025
Department of Chemical and Biological Engineering, Department of Chemistry, Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science & Technology, Hong Kong, 999077,
Breast cancer (BC), characterized by its heterogeneity and diverse subtypes, necessitates personalized treatment strategies. This study presents MF3Ec-TBPP nanoparticles (NPs) as a promising approach, integrating an aggregation-induced emission (AIE)-based photosensitizer, TBPP, with the MF3Ec aptamer to enhance targeted photodynamic therapy (PDT) for Luminal A subtype BC cells. The nanoparticles also feature a 1, 2-distearoyl-sn-glycero-3-phosphoethanolamine-poly(ethylene glycol) shell and dipalmitoyl phosphatidylcholine (DPPC), which stabilize the structure and inhibit singlet oxygen generation, effectively reducing off-target effects and protecting healthy tissues.
View Article and Find Full Text PDFJ Am Chem Soc
September 2025
Kathleen Lonsdale Materials Chemistry, Department of Chemistry, University College London, London WC1H 0AJ, U.K.
The exceptional performance of ceria (CeO) in catalysis and energy conversion is fundamentally governed by its defect chemistry, particularly oxygen vacancies. The formation of each oxygen vacancy (V) is assumed to be compensated by two localized electrons on cations (Ce). Here, we show by combining theory with experiment that while this 1 V: 2Ce ratio accounts for the global charge compensation, it does not apply at the local scale, particularly in nanoparticles.
View Article and Find Full Text PDFAnal Chem
September 2025
Department of Radiotherapy, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215123, People's Republic of China.
Radiation therapy (RT) plays important roles in cancer treatment, and the efficacy of RT depends on the abscopal effect, which results in the regression of distant and untreated tumors through localized irradiation of a single tumor lesion. This effect is mediated by effector tumor antigen-specific T cells (ETASTs) activated by RT. Monitoring the radiation-induced changes in ETASTs can be used to predict the abscopal effect.
View Article and Find Full Text PDFChemistry
September 2025
Department of Molecular Theory and Spectroscopy, Max-Planck-Institut für Kohlenforschung, 45470, Mülheim an der Ruhr, Germany.
In this study, we seek to deepen the understanding of the Fe effect in Ni-oxyhydroxide-mediated oxygen evolution reaction (OER) electrocatalysis in alkaline conditions, where extremely small amounts of Fe can have a dramatic impact on catalytic performance. For this purpose, Density Functional Theory (DFT) electronic structure calculations with implicit solvation description is employed in a constant pH/potential simulation framework. Nanoparticle models are considered for the nickel-based oxyhydroxide material with different degrees of Fe incorporation, and the pH/U-dependent interface structure is studied.
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