Objective

• To synthesize novel ZnO hierarchical structures for high efficiency DSSCs.
• To solve the stability problem of the conventional DSSCs based on liquid electrolyte.
• Rational design of the device structure to improve the efficiency.
• Investigation of the optical and electrical properties of the solar cell devices.

Approach

• The ZnO hierarchical structures are obtained by a facile direct precipitation method.
• The solar cell devices are fabricated by doctor-blade approach with the quasi-solid electrolyte sandwiched between the ZnO film and counter electrode.

Impact

• Up to now, most of the reported ZnO-DSSCs are fabricated with liquid electrolytes. Therefore, the long-term durability is poor due to the surface chemistry problem at the ZnO/dye/electrolyte interfaces. Compared with this, our quasi-solid electrolyte can effectively avoid this problem, which is suitable for practical application.
  
   
• The efficiency of our ZnO hierarchical structures based DSSCs has achieved 6.83% . This is the record efficiency for quasi-solid ZnO DSSCs, and the second high efficiency for all kinds of ZnO DSSCs (the highest efficiency of ZnO DSSCs is 7.5%, based on the liquid electrolyte).
  
   
• The direct precipitation for massive production of ZnO hierarchical structures is a facile and economical method. This approach does not involve high temperature treatment and complex experimental process. This feature is very favorable for the industrial production.

Contact

Ning Wang, Professor of Physics
Email: phwang@ust.hk