2013 Fiscal Year Final Research Report
Application of grain boundary function to develop new materials for solar cells with high performance
| Project/Area Number |
23656435
|
|---|
| Research Category |
Grant-in-Aid for Challenging Exploratory Research
|
| Allocation Type | Multi-year Fund |
|---|
| Research Field |
Structural/Functional materials
|
|---|
| Research Institution | Kumamoto University |
|---|
Principal Investigator |
|
|---|
| Research Collaborator |
YAMAMURO Takateru 熊本大学, 工学部, 技術専門職員
|
|---|
| Project Period (FY) |
2011 – 2013
|
| Keywords | 太陽電池 / 粒界 / ポテンシャル障壁 / 電気伝導 / CdTe / Si / KFM / 第一原理計算 |
|---|
| Research Abstract |
The motivation of this work was to study the origin of grain boundary function suitable for achieving enhanced conversion efficiency of microcrystalline CdTe solar cells, and then to obtain a principle of grain boundary design for development of new materials for solar cells with high performance. We have found the potential barrier associated with grain boundaries in CdTe depends not only on grain boundary character but also on polarity at grain boundaries arising from its crystal structure. In addition, the CdCl2 treatment, which increases the conversion efficiency of CdTe solar cells, was found to increase the grain boundary potential barrier. These findings show that grain boundaries in CdTe can act as the built-in potential for separation of photogenerated hole - electron pairs, and that Cl segregation to grain boundaries after the CdCl2 treatment would result in the enhancement of the role of the built-in potential rather than the passivation of defect states in the band-gap.
|
