Collaborative Research: Polymer-Guided Synthesis of Symmetry-Breaking Nanostructures with Hierarchical Multimaterial Interfaces

In this project, Dr. Jie He of the University of Connecticut and Dr. Shouheng Sun of Brown University will study the design of hierarchical multifunction interfaces guided by polymer templates. Conventional materials synthesis methods tend to yield symmetrical structures, giving uniform interfaces that limit their ability to selectively regulate ion transport, intermediate retention, and synergistic reactivity between multiple catalytic components. This collaborative project will address this challenge by establishing a new synthetic strategy to create symmetry-breaking nanocomposites composed of polymers and metals (or metal oxides). The central component is the polymer-coated nanoparticle seed with one region being protected by polymer ligands while the remaining surface remains exposed to solution and serves as an anchoring site. This structural asymmetry enables the selective growth of secondary metal domains on the uncovered regions, allowing precise control over nanostructure composition, porosity, and interfacial architecture. Multicomponent nanoparticles, including polymer-Au(Ag)-Cu and polymer-Au(Ag)-CuM heterostructures will be prepared with interconnected yet spatially isolated Cu surface ensembles, where M represents another transition metal to form Cu-based alloys. These cooperative interfacial interactions are expected to create new reaction pathways and enhance catalytic selectivity for complex chemical transformations. The project will provide integrated research and educational opportunities for graduate and undergraduate students at UConn and Brown University, while also expanding outreach to the broader community. The PIs will establish a Chemistry Boot Camp for High School Students, envisioned as an annual enrichment program serving local high schools across New England region. This collaborative project aims to establish a new synthetic principle for the design of symmetry-breaking multicomponent nanocomposites composed of polymers and metals (or metal oxides) for cooperative catalytic transformations. The proposed system is based on the strategic control of structural asymmetry and interfacial composition to regulate ion and molecular transport across polymer-metal and metal-metal interfaces. The system consists of nanoparticle (NP) seeds partially coated with polymer ligands and partially exposed to solvent, generating asymmetric surface environments that spatially confine the growth of secondary metal domains to ligand-deficient regions. Using Cu and Cu-containing bimetallic nanoparticles as model systems, the synthetic methodology will provide precise control over domain size, morphology, composition, interfacial strain, and porosity of Cu domains in polymer-Au(Ag)-Cu and polymer-Au(Ag)-CuM heterostructures. The team will extend the synthetic approach to polymer-Au(Ag)-Cu(0)-Cu(I) heterostructures, where Cu(I) originates from Cu2O, to investigate interfacial reactivity and synergistic catalytic effects relevant to electrochemical C-C and C-N coupling reactions. The polymer-metal interface will be designed to regulate the transport of protons, ions, and small molecules, while the heterometallic interface will control the spillover, confinement, and retention of reactive intermediates such as CO. The integration of these interfaces within a single nanostructure is expected to create new modes of interfacial cooperativity and selectivity control for complex multisite reactions. A versatile synthetic platform for the spatially precise construction of ligand-heterometal nanostructures with tunable architectures and compositions will offer new opportunities to understand transport-regulated interfacial substrate activation in multicomponent nanoscale systems. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.