KU Researchers Develops High-Performance Graphene Counter Electrodes

Nitrogen-doped Graphene Electrode

Korean researchers succeeded in developing the technology to synthesize dye-sensitized solar cell counter electrodegraphene, and it is expected to be actively utilized for developing highly efficient dye-sensitive solar cells in the future.

*Counter Electrode: The electrode that acts as a catalyst for reducing the electrolytes which were used for reducing the oxidized dye in dye-sensitized solar cells.

*Graphene: A detached layer of the multi-layer graphite which consists of stacked layers of carbon planes. It draws attention as a dream material due to its superior electrical and thermal conductivity and strength.

This research was led by Professor Hwan-Kyu Kim’s research team in the Department of New Materials Engineering in the College of Science and Technology with the support of the ‘New Fusion Technology Growth Engine Project’ of the Ministry of Science, ICT, and Future Planning (Minister Moon-Ki Choi). This research was conductedfor the purpose of developingthe mass-production technology ofnitrogen-doped graphene,utilizing it asa dye-sensitized solar cell counter electrode.It is anticipated that the commercialization of dye-sensitized solar cells will be accelerated by implementing low-cost, high-efficiency, and long-life dye-sensitized solar cells.

*Nitrogen-Doped Graphene: The status that some carbon atoms that make up graphene are replaced with nitrogen atoms.

Manufacturing highly efficient and stablesolar cellshas limitations because platinum counter electrodes used in previous studies have a high manufacturing cost and the disadvantage of corrosion in the course of oxidation-reduction reaction of electrolytes. However, the newly developed nitrogen-doped graphene counter electrode hasmore superior catalytic properties and electrochemical stability than platinum counter electrodes, and isenvironmentally friendly since it is metal-free and corrosion-free.In addition, it is expected to replace conventional platinum electrodes because it is possible to mass-produce low-cost counter electrodesby using inexpensive graphite and a simple manufacturing process.

The research team manufactured nitrogen-doped graphenevia heat treatment after selectively applying the amino groupat the edges of the graphite. As a result of its use  asa dye-sensitivity solar cell counter electrode, excellent solar cell conversion efficiency (9.3%) was obtained in the field of graphene-based dye-sensitized solar cells.

*The amino group (-NH2): The organic functional group in whicha nitrogen (N) atom and two hydrogen atoms (H) are combined.

This research appeared in the June issue of ACS Nano, a prestigious journal in the field of nanotechnology and materials engineering (Title: N-Doped GrapheneNanoplatelets as Superior Metal-Free Counter Electrodes for Organic Dye-Sensitized Solar Cells).

Professor Hwan-Kyu Kim assessed that“this research laid the foundation for the early commercialization of dye-sensitized solar cells by developingan alternative material withlow cost, high stability, and high efficiency, which will overcome the limitations of conventional platinum counter electrodes.