Hierarchical Molecular Design at Organic-Inorganic Hybrid Lattices

The pursuit of next-generation materials to address the energy and sustainability crisis hinges on hybrid crystalline systems, particularly layered lattices with well-defined organic-inorganic interfaces. These materials harness the vast chemical space of organics and the superior electronic, photonic, or catalytic performance of inorganics, making the assembly tunable and solution processable. While organic sublattices play crucial roles directing overall functionality, these building blocks rarely extend beyond lattice-construction purposes and single molecular behaviors, which limit the capabilities of these emergent materials. Redefining the complex layered lattice necessitates a circular and hierarchical molecular design to escalate and converge multi-level structure-function relationship.

This talk will begin with the fundamental small molecule semiconductors. I will guide you through the foundational principles of molecular design, demonstrating how we can precisely tune their excited-state profiles by converging molecular photochemistry with theory and modeling.

Next, we advance to complex structure-function relationships within layered lattices constructed by precisely designed organic building blocks and inorganic scaffolds. Using layered perovskite as a structural template, I will discuss several molecular templating strategies that allow us to manipulate the network topology within the organic sublattice, achieving sophisticated morphological control that extends beyond traditional 2D materials. Recently, our topological modifications enabled the synthesis of high-quality layered perovskite nanowires with tunable chemical compositions, including the creation of longitudinal heterostructures. These nanowires form exceptionally well-defined and flexible cavities that exhibit a wide range of unusual optical properties.

The molecular structural chemistry within a layered hybrid lattice resembles organic crystal engineering within a confined space, diverging significantly from conventional organic chemistry. Finally, we will look ahead to explore how a hierarchical molecular design approach can enable the construction of even more complex hybrid lattices, unlocking the hidden potential of these materials for futuristic atomically precise reactors, gas storage systems, and quantum photonics.

Dr. Wenhao Shao is currently a Postdoctoral Associate at the Davidson School of Chemical Engineering, Purdue University. He obtained his B.S. from Fudan University in 2017 and Ph.D. from University of Michigan in 2022, both in Chemistry. His research focuses on designing organic building blocks for purely organic and organic-inorganic hybrid materials. The design transfers molecular orbital manipulation and molecular-level interactions to crystal structures and morphologies, and ultimately the photonic and electronic properties.