Fuel cells and Li-ion batteries are promising substitutes for the nearly depleted fossil fuels because of their high energy density. The unique physical and chemical properties of graphene endow it huge potential in energy conversion and storage. Recently, Professor Yanglong Hou’s group in the Department of Materials Science and Engineering, College of Engineering, Peking University, achieved a series of breakthroughs in graphene-based energy materials.

The sluggish cathode oxygen reduction reaction (ORR) in a fuel cell (O2 +4e- → 4OH-) usually needs to be catalyzed by noble metals. Yanglong Hou group designed a novel hybrid of iron nitride and nitrogen-doped graphene aerogel which exhibited comparable catalytic activities to commercial Pt/C in alkaline media while possessed superior stability and selectivity. Its excellent catalytic performance together with its low cost enable it the potential to replace expensive Pt-based catalysts in fuel cells. The research article titled “Hybrid of Iron Nitride and Nitrogen-Doped Graphene Aerogel as Synergistic Catalyst for Oxygen Reduction Reaction” has been published in Advanced Functional Materials ( http://onlinelibrary.wiley.com/doi/10.1002/adfm.201303902/abstract ).

In addition, the hybrid of core-shell Co3Sn2@Co nanoparticles and nitrogen-doped graphene (Co3Sn2@Co-NG) can be applied as high-performance anode materials for Li-ion batteries. The encapsulation of Co shell and graphene substrate greatly enhanced the stability of the anode material. Co3Sn2@Co-NG hybrid exhibits extraordinary reversible capacity of 1615 mAh/g at 250 mA/g after 100 cycles with excellent capacity retention of 102%, demonstrating significant application prospect. The research paper has been published in ACS Nano titled “Hybrid of Co3Sn2@Co Nanoparticles and Nitrogen-Doped Graphene as a Lithium Ion Battery Anode” ( http://pubs.acs.org/doi/abs/10.1021/nn4047138 ).

Recently, Yanglong Hou group was invited to publish a feature article titled “Graphene-based Nanocomposites For Energy Conversion and Storage in Lithium Batteries, Super Capacitors and Fuel Cells” in Journal of Material Chemistry A ( http://pubs.rsc.org/en/content/articlelanding/2014/ta/c3ta13033a ). The article systematically reviewed graphene and its derivatives for energy storage (Li-ion batteries, Li-air batteries, Li-S batteries and supercapacitors) and conversion (ORR), summarized the design principles and challenges of energy materials, and looked into its future prospects.

The first author of the first paper is Han Yin, a senior undergraduate from the Department of Materials Science and Engineering, and the 1st author of the latter two articles is Nasir Mahmood, a 3rd year Ph.D. candidate in Prof. Hou’s group. These projects are supported by National Natural Science Foundation of China, Beijing Natural Science Foundation and National Undergraduate Innovation Training Program.