从二维到一维的电子维度在化佩洛夫斯基特中,使用作为间隔器
Justin M Hoffman1, Xiaoyang Che2, Siraj Sidhik3
1Department of Chemistry , Northwestern University , Evanston , Illinois 60208 , United States.
Journal of the American Chemical Society
|June 28, 2019
概括
新的基于的二维化物矿,包括Ruddlesden-Popper (RP) 和阶段式 (SL) 结构,为光电子应用提供可调节的带隙和异性电子特性.
科学领域:
- 材料科学
- 固态物理
- 光电子产品
背景情况:
- 由于对3D对应物的增强稳定性,二维 (2D) 混合化矿被用于光电子.
- (PA+) 离子被引入以创建新的矿结构.
研究的目的:
- 用 (PA+) 离子合成和描述新的二维矿结构.
- 研究这些新材料的电子和光学特性.
- 评估它们在太阳能电池应用中的潜力.
主要方法:
- 拉德尔斯登 - 波珀 (RP) 和阶段式 (SL) 矿结构的合成.
- 用光学特征来确定带隙.
- 用于电子结构分析的密度功能理论 (DFT) 计算.
- 电阻测量
- 太阳能电池的制造和测试
主要成果:
- RP结构 ((PA) 2 ((MA) n-1PbnI3n+1) 呈现可调的蓝移带间隙 (1.90-2.03 eV) 和异能导电性.
- SL结构 ((PA) 2 ((MA) m-1Pb2Im+2) 显示出较大的蓝移 (2.53-2.93 eV),并且在电子上是1D量子线.
- RP晶体表现出强烈的光响应,而SL材料表现出离子运输的主导性和没有光响应.
- 使用RP结构 (n=3) 制造的太阳能电池以最小的hysteresis实现了7.04%的效率.
结论:
- 新的基于PA+的RP和SL矿具有不同的电子结构和异性质.
- RP结构适用于光电子设备,如太阳能电池,显示出有前途的效率.
- 虽然SL结构不具有光敏性,但具有独特的1D电子特性.
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