PhD Dissertation Defense: Hailiang Wang (31 May, Thursday at 10:00am)

Department of Chemistry

University PhD Dissertation Defense  

 Inorganic/Graphene Hybrid Nanomaterials for Supercapacitors and  Batteries

Hailiang Wang

Advisor: Prof. Hongjie Dai

 

Date: Thursday, May 31st, 2012

Time: 10:00 am (Breakfast served at 9:40 am)

Location: 200-034 (Lane History Corner, Main Quad)

Energy storage is to become more and more important with the gradual shift from fossil fuels to renewable energy sources which are temporally intermittent and geographically localized. On the other hand, electric vehicles are now a trend in the automobile industry with the goal to cut emission and reduce oil consumption. It is thus crucial to develop electrochemical energy conversion and storage devices such as batteries and supercapacitors with high specific energy and power, long cycle life, low cost and safety.

We design and synthesize novel nanostructured electrode materials and electrocatalysts by using chemically derived graphene sheets as growth substrates for electrochemical functional materials. The unique chemical interactions between graphene and the active nanomaterials affect the morphology and size of the nanomaterials, enhance electron transport, stabilize the nanomaterials during cycling, and generate synergistic effects in electrocatalysis, leading to superior electrochemical performance. 

We have grown nanocrystals of hydroxides, oxides, chalcogenides and phosphates with controlled morphology, sizes and structures on graphene, affording materials that can be readily integrated in current lithium ion batteries, alkaline batteries and supercapacitors to boost their performance, as well as materials that supports rising technologies such as Li-S and Li-air batteries. The novel materials we have studied also allow for deepening our understanding in materials chemistry and electrochemistry.