Nanochemistry seminars

Xingchen Ye and Hanyi Duan explain how ultraviolet, visible, and near-infrared spectroscopy provides rapid, nondestructive measurements of nanomaterial optical properties. The presentation connects spectra to electronic transitions, band gaps, particle size, aggregation, and surface-plasmon resonance. Applications to metallic and composite nanomaterials include tracking nanoparticle formation, assessing colloidal stability, estimating optical band gaps, and detecting changes caused by surface modification or interactions with other chemical species. The talk develops practical approaches for interpreting these measurements during synthesis and characterization.

Producing metal-organic frameworks as nanoparticles could make them easier to process at industrial scale and change properties such as transport. Controlled synthesis and the effects of particle size remain insufficiently understood. Carl K. Brozek presents synthetic methods and mechanistic models for preparing MOF nanoparticles whose electrical conduction, magnetism, optical response and dynamic bonding differ from bulk frameworks. Solution-state spectroscopy and electrochemistry expose size-dependent and interfacial effects that conventional framework materials do not reveal. The work provides approaches for scalable MOF manufacture while raising broader questions about relationships among structure, size and properties. Speaker: Associate Professor Carl K. Brozek, University of Oregon, Department of Chemistry and Biochemistry. Hosted by Jack Zhang and Kevin Kittilstved for Washington State University Chemistry. Monday 19 October 2026, 16:10–17:00 America/Los_Angeles (Pacific Daylight Time). Attend at Fulmer Hall, Room 201, Washington State University, Pullman, Washington, USA, or use the public Zoom Link on the official event page.

Leonardo Fernandes Fraceto explores the development of nanoherbicides for more efficient, sustainable weed control. This Spanish-language webinar covers design strategies, interactions between nanomaterials and plants, controlled release, reduced herbicide doses and potential reductions in environmental impact. It examines how these principles could support more precise crop management and discusses the practical benefits, barriers and opportunities associated with adopting nanoherbicides in real agricultural systems. Speaker: Dr. Leonardo Fernandes Fraceto, Universidade Estadual Paulista, Brazil. The registration page also lists Dr. Ingrid Montes, Universidad de Puerto Rico, Recinto de Río Piedras. Co-produced by ACS Webinars and Sociedad Química de México. Wednesday 30 September 2026, 14:00–15:00 America/New_York (EDT); the live registration page confirms 20:00 CEST. Online via Zoom Events, free registration required. Follow Regístrese Gratuitamente on the ACS event page to the verified Zoom Events registration page. A free ACS ID may be required. Slides are scheduled to be available on the webinar day.

Aleksey Yekimov, Louis Brus and Moungi Bawendi trace the discovery and chemical development of quantum dots: semiconductor particles whose electronic and optical behaviour changes with their size. Yekimov examines confinement effects in small crystals embedded in glass, while Brus develops the study of semiconductor particles dispersed in solution. Bawendi explains the synthetic challenge of producing high-quality nanocrystals with controlled dimensions and how more reliable preparation made their properties experimentally and practically useful. The lectures bring together the physics of confinement, the chemistry of colloidal materials and the control of particle growth, showing why both discovery and synthesis were essential to the emergence of quantum-dot science.

Self-organized complex structures in nature, e.g., viral capsids, hierarchical biopolymers, and bacterial flagella, offer efficiency, adaptability, robustness, and multi-functionality. Can we program the self-assembly of three-dimensional (3D) complex structures using simple building blocks, and reach similar or higher level of sophistication in engineered materials? Here we present an analytic theory for the self-assembly of polyhedral nanoparticles (NPs) based on their crystal structures in non-Euclidean space. We show that the unavoidable geometrical frustration of these particle shapes, combined with competing attractive and repulsive interparticle interactions, lead to controllable self-assembly of structures of complex order. Applying this theory to tetrahedral NPs, we find high-yield and enantiopure self-assembly of helicoidal ribbons, exhibiting qualitative agreement with experimental observations. We expect that this theory will offer a general framework for the self-assembly of simple polyhedral building blocks into rich complex morphologies with new material capabilities such as tunable optical activity, essential for multiple emerging technologies.