CAS: Collaborative Research: Solar CO2 Reduction by Atomically Dispersed Metal Sites on Few-Layer Carbon Nitride

With the support of the Chemical Catalysis program in the Division of Chemistry, Gonghu Li of the University of New Hampshire, N. Aaron Deskins of Worcester Polytechnic Institute and Anatoly Frenkel of Stony Brook University will study new catalysts based on earth-abundant elements to recycle carbon dioxide to produce energy-rich fuels. The catalysts will be prepared by placing isolated metal ions on a polymeric material that can absorb sunlight and stabilize the metal ions.

The catalyst structure will be investigated using advanced techniques at the Brookhaven National Laboratory aided by computational modeling. This project will employ carbon dioxide as a renewable C1 feedstock and utilize light as the only energy input for this chemical transformation. Through this process, it is expected that solar energy will be converted into chemical energy and stored in the form of chemical bonds.

This project focuses on fundamental research in catalysis and provides a versatile platform for training students in STEM (science, technology, engineering and mathematics) fields. The project will also provide excellent opportunities for full participation of women and underrepresented minorities in clean energy, catalysis and nanoscience.

With the support of the Chemical Catalysis program in the Division of Chemistry, Drs. Gonghu Li of the University of New Hampshire, N. Aaron Deskins of Worcester Polytechnic Institute and Anatoly Frenkel of Stony Brook University will study heterogeneous photocatalysts containing molecularly defined active sites with the goal of building a system for efficient solar fuel generation.

Innovative photocatalysts will be prepared by coordinating atomically dispersed cobalt sites on few-layer graphitic carbon nitride, which is to serve not only as a visible-light absorber but also a “ligand” to coordinate with and activate the cobalt centers for catalysis. The synthesized photocatalysts will be investigated using X-ray absorption fine structure (XAFS) spectroscopy and computational modeling, and evaluated in their ability to catalyze the reduction of carbon dioxide to useful chemicals and fuels.

The collaborative team will focus on constructing highly active Co-N4 moieties on carbon nitride to elucidate structure-function relationships of such cobalt sites. Through the proposed studies, the research team seeks to answer fundamental questions regarding the desired structure of atomically dispersed cobalt sites on few-layer carbon nitride, the effect of carbon-doping on photocatalytic properties, and the mechanism of carbon dioxide reduction at such cobalt sites.

The combined experimental and theoretical approach holds promise to improve general understanding of the structures of such catalysts and how these structures correlate with activity at the molecular level. This project has the potential to develop active catalysts for small molecule activation and solar energy conversion.

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.