1. Solar Energy Conversion using Hybrid Photocatalysts
where Molecular Catalysis meets Surface Chemistry and Materials Science
The Group, Department of Chemistry & Materials Science Program
University of New Hampshire, Durham, NH 03824
Motivation: Solar Fuel Generation via CO2 Reduction
Solar energy is the most abundant renewable energy source available, yet we still lack efficient and robust devices for solar energy conversion;
Carbon dioxide is a renewable C1 feedstock for the production of chemicals, materials, and fuels;
Molecular catalysts based on metal-ligand complexes are highly efficient in mediating multi-electron CO2 reduction (CO2 + 2e- + 2H+  CO + H2O);
Combining molecular catalysts with nanostructured surfaces improves catalyst stability, enhances reactivity & enables novel reaction pathways.
Our Approach: Bridging Molecular Catalysis with Surface Chemistry
Homogeneous
Molecular Catalysts
Heterogeneous
Surface Catalysts
Project #1: Heterogenization of Molecular Catalysts
Project #3: Exploring Highly Active Catalytic Sites in Metal/TiO2 Nanocomposites
CO-Cu+ Cu e- e- hv hv e- h+ h+
TiO2
TiO2
Highly active, tunable
Molecular understanding
Poor stability/recyclability
Very stable, recyclable
Inexpensive, easy to prepare
Lack of molecular understanding
Surface metal sites inhibit charge recombination (dotted line) and serve as hotspots for CO2 reduction
IR spectra of CO adsorbed on two Cu/TiO2 photocatalysts
Project #4: Environmental Photocatalysis
Dye Degradation
Molecular
Catalyst
Time hv
Light
Absorbing
Linkage
SiO2
TiO2
Collaborators
Dr. Richard Johnson, UNH
Dr. Dunwei Wang, Boston College
Dr. N. Aaron Deskins, WPI
Dr. Jay Agarwal, Univ. of Georgia
Dr. Etsuko Fujita, Brookhaven
Dr. Tijana Rajh, Argonne
Project #2: Coupling Catalysts with Energy Sources
Electron
Sink
Li Lab Instruments
Transmission FTIR Spectrometer
DRIFTS Spectrometer
UV-Vis Spectrophotometer
Electrochemical Station
BET Surface Area Analyzer
Gas Chromatograph
CO2 CO e- h+ hv D+ D
Photocatalysis
Outreach Activities: Solar Energy Workshops for High School Teachers e- hv
Conditions:
TEOA/MeOH
UV light D h+ D+
Photoelectrochemical CO2 Reduction
Funding
NSF CAREER Award
(#CHE )
NSF #CBET
Contact Information
Gonghu Li, Associate Professor
Department of Chemistry &
Materials Science Program
Phone:
Silicon Nanowires
(courtesy of Dr. Dunwei Wang)