Computational approach to investigating effects of molecular structures in dye-sensitized solar cells on open-circuit photovoltage to design the structures such as ligand of sensitizer complex

2019 Fiscal Year Final Research Report

• Project/Area Number: 16K05889
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Energy-related chemistry
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: KUSAMA Hitoshi 国立研究開発法人産業技術総合研究所, エネルギー・環境領域, 上級主任研究員 (70356913)
• Project Period (FY): 2016-10-21 – 2020-03-31
• Keywords: 色素増感太陽電池 / 量子化学計算 / 構造物性相関 / 増感色素 / レドックス / 分子間相互作用

Outline of Final Research Achievements

Factors associated with the open-circuit photovoltage (Voc) of dye-sensitized solar cells (DSSCs) were computationally investigated using density functional theory (DFT). For the n-type (p-type) DSSCs, intermolecular interactions of dye with electron acceptor (donor) such as iodine molecule (anion radical) can accelerate the recombination process by changing the concentration of the electron acceptor (donor) near the n-type (p-type) semiconductor surface such as TiO2 (NiO). The closer the binding site of the acceptor (donor) to the semiconductor surface, the faster will be the recombination of injected electrons (holes) in the semiconductor with the acceptor (donor) in the electrolyte, decreasing Voc. Based on the computational findings, we showed a new molecular design of dye for better Voc in DSSCs.

Free Research Field

エネルギー関連化学

Academic Significance and Societal Importance of the Research Achievements

ｐ型酸化物半導体へ注入された正孔と電解質中の電子供与体との再結合機構を明らかにすると共に、ｐ型色素増感太陽電池における色素還元体の再酸化機構を初めて提案した点で学術的意義は大きい。さらに、太陽電池のみならず水分解水素製造による水素エネルギー分野などへの応用が考えられ、将来的に再生可能エネルギーを普及拡大するという社会的意義も認められる研究成果である。