CAREER: Multi-atomic Layered Electronic Metal-organic Materials

University Of Wisconsin-Madison, Madison WI

Investigators

Abstract

NON-TECHNICAL SUMMARY Metal-organic hybrid materials (MOMs), such as coordination complexes, coordination polymers (CP), and metal-organic frameworks (MOFs), possess vast structural diversity and thus have been extensively investigated for magnetism, catalysis, sensing, gas storage and separation, and biomedical applications. Ideally, embedding the synthetic tunability of MOMs with the electronic properties (e.g., electrically conductive MOMs, called eMOMs) would expand the molecular functionality of conventional inorganic electronic materials, offering new opportunities to address challenges in many vital electronic/electrochemical devices, including wearable devices, sensors, electrocatalysts, and electrochemical energy storage. Unfortunately, to-date conventional MOMs are primarily insulators by nature. With this CAREER project, supported by the Solid State and Materials Chemistry program in the Division of Materials Research, Prof. Dawei Feng studies a general approach to synthesize new types of eMOMs based on two dimensional (2D) multiple layered atomic structures (M-eMOMs). This research utilizes the structural diversity of MOMs to unlock their full potential in advanced electronic and electrochemical devices. The PI and his team also partner with the Materials Research Science and Engineering Centers (MRSEC) education group and the Institute for Chemical Education (ICE) at University of Wisconsin-Madison to organize “Make MOFs at home” after school enrichment program. Through the integrated education plans, middle schoolers get hands-on experiences in synthesizing MOMs using safe, daily accessible materials to foster their interests in STEM, and undergraduate and graduate students receive interdisciplinary training in materials science, chemistry, and fabrication of energy storage devices. TECHNICAL SUMMARY The compositional diversity and synthetic tunability of metal-organic materials (MOMs) give them great potential for a series of applications where precise tuning of structures and functionalities plays a vital role. Integration of electronic properties (e.g., electronic conductivity) into MOFs is of particular interest as it adds diverse functionalities on top of electronic properties, which greatly enriches the class of current electronic materials and the scope of their applications. However, the majority of MOMs are insulators with just a few exceptional examples, most of which adopt single atomic layered p-d π conjugated 2D structures. This NSF CAREER project develops new classes of electronically conducting MOMs, called eMOMs through assembling multi-atomic layered 2D structures with p-d σ conjugation, namely M-eMOMs. The metal species and organic ligands are systematically micro-tuned to manipulate the electronic characteristics and functionality of M-eMOMs. Kinetically controlled synthetic methodologies are adopted to achieve highly crystalline M-eMOM products for precise measurement of their intrinsic properties. This permits elucidation of fundamental aspects of interactions between the metal and organic building units and the subsequent impact on the bulk electronic properties. In turn, this research is poised to enable applications in various areas, including electrocatalysis and flexible electronic devices. This work not only provides a new platform to integrate metals with organic building units but also introduces new 2D material candidates with vastly expanded molecular engineering potential. 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.