研究期間：10108~10207;Increasing energy demands and concerns over global warming have led to a greater focus on renewable energy sources in recent years. Dye-sensitized solar cells (DSSCs) have a significant potential to be used as low-cost photovoltaic devices for light to electricity conversion. Gratzel and co-workers investigated ruthenium(II) polypyridyl complexes such as N3, N719 and Black dye exhibiting highly efficient light harvesting properties. Many researchers also explored inexpensive metal free organic sensitizers with different electron donor and acceptor systems having high molar extension coefficient. Among dyes with different strong donating groups, cynoacrylic acid as an electron acceptor showed excellent photovoltaic properties. Recently, worldwide researchers geared their attention to further improve the photoelectric conversion efficiency of sensitizers. Most modifications were carried out using various conjugate substituents on ancillary ligand of ruthenium(II) polypyridyl complexes or employing different donor and acceptor groups in organic dyes. The main objective of this research proposal is to develop stable and highly efficient sensitizer dyes for DSSC applications. Specific aims are: A. Rational design and synthesis of N-heterocyclic carbene (NHC) pyridine-based ruthenium(II) complexes: 1. To apply present, and also formulate new methodologies of synthesis to prepare proposed NHC pyridine-based ruthenium(II) complexes. 2. To identify the critical structural requirements of NHC pyridine-based ruthenium(II) complexes and to achieve the desired power conversion efficiency through structure-function analysis. 3. To generate several stable and highly efficient NHC pyridine-based ruthenium(II) complexes for dye-sensitized solar cell applications. B. Photoelectric conversion efficiency evaluation of various organic dyes: 1. To prepare a new generation of organic dyes with conformational constrain around the cynoacrylic acid moiety (acceptor group). 2. To evaluate the power conversion efficiency of the constrained dyes and correlate their efficiencies with the corresponding geometry in order to design more efficient cynoacrylic acid sensitizers. 3. To explore several new organic sensitizers with different donor and acceptor systems or develop dyes with other acceptor group and study the correlation between device performances with structural modifications. C. Discovery of novel ruthenium free organic metal-hybrid sensitizers: 1. To design and synthesize various ruthenium free organic metal-hybrid sensitizers using combinatorial approach. 2. To evaluate the photovoltaic properties of the identified hits. 3. To optimize and fine tune device conditions between dyes and the semiconductor films with a different mesoscopic oxides’ layer.
