
Sustainable Use of Carbon for Energy
Burning of carbon-rich substances (such as coal) has been a major source of energy we use today. It not only depletes resources but also adversely impact the environment. With the colloidal graphene quantum dots we are exploring renewable ways to use carbon for energy. Our work in this direction focuses on using the quantum dots for photovoltaics, photocatalytic CO2 reduction and water splitting, and electrocatalytic oxygen reduction reaction (ORR).Carbon Materials for Biomaging and Cancer Therapy
The graphene quantum dots we study have some unique properties for biological applications. For example, they have size-dependent light absorption and emission. With moderate size (~2 nm) they can absorb and emit near-infrared light that can penetrate tissues. They also have well-defined molecular structures and chemistry so that we can precisely attached various functionalities to selectively interact with bimolecules such as proteins and DNA. Our work in this direction focuses on making water-soluble graphene quantum dots and studying their applications in bioimaging and photo-induced cancer therapy.Carbon materials have played extremely important roles in many applications ranging from pigments, adsorbents, to batteries and catalysts. However, heterogeneity and complexity of these materials have seriously limited our understandings and hindered development of new applications of them. Our work in this direction aims to develop molecular-level understandings of some fundamental processes in these complex materials for energy storage and catalysis.

