Metaloxide films deposited by a nonequilibrium 2D plasma in a liquid phase and their application to ye-sensitized solar cell

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K06817
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Composite materials/Surface and interface engineering
• Research Institution: Shizuoka University
• Principal Investigator: Okuya Masayuki 静岡大学, 工学部, 准教授 (00293605)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 非平衡二次元プラズマ / 誘電体バリア放電 / 薄膜 / 色素増感太陽電池

Outline of Final Research Achievements

A non-equilibrium two-dimensional plasma was induced in a small cavity between an insulating electrode and a glass substrate by introducing a gas in a liquid phase.　A pre-sintered porous-TiO2/FTO double layered glass substrate was set below the electrode for discharge to face each other in the　Titaniumtetraisopropoxide solution. The oxidization process was promoted with irradiating a plasma to the precursor spread on a glass substrate by a capillarity.
After the plasma treatment, the surface of the TiO2 layer was found to be porous with the particle size of 10 to 20 nm, which is almost comparable to a typical dye-sensitized solar cell. The conversion efficiency reached as high as 3.7 % for the cell prepared under N2/O2 mixture gas. We found that the active plasma species originated from N2 gas played an important role in the oxidation and crystallization in the film formation to enhance the necking process between TiO2 particles.

Free Research Field

無機材料

Academic Significance and Societal Importance of the Research Achievements

一般的なプラズマを利用した製膜では、基板に対し高エネルギープラズマへの耐抗性・耐熱性が要求され、汎用的な低融点基板への適用が難しい。さらに、マスキングやレジストといった追加処理が要求される。一方、液相からの化学的手法による低温製膜やパターニングにおいて、バルクの液相中では均一分散している修飾子であっても、溶媒を除去する過程で基板からの影響を強く受ける。
本研究では独自に開発した大気圧非平衡平面プラズマによる製膜技術を発展させ、液相中の微小空洞へのプラズマ閉じ込め効果を利用した新規製膜技術の確立、およびその応用を目的とする新たな研究である。