Absorption spectrum of germanium solar cells

How do germanium-based solar cells improve absorption efficiency?

In this paper, germanium-based solar cells were designed based on germanium (Ge) materials, and the cross-cone (CC) nanostructures were used as the absorber layer of the solar cells. The optical path inside the absorber layer was increased by microstructure reflection, thereby increasing the absorption efficiency of the germanium-based solar cell.

What are the electrical properties of germanium-based solar cells?

The devices obtained in this study have good electrical properties. The VOC of the germanium-based solar cells under the single-junction CC nanostructure absorber structure array is 0.31 V, and the JSC reaches 45.5 mA/cm 2. The FF value of the device can be calculated as 72.7% by Equation (4).

What are the research findings on multijunction germanium based solar cells?

In 2016, Masuda [ 12] reported on the growth of multijunction germanium-based solar cells based on molecular beam epitaxy technology, and the open-circuit voltage of ~0.175 V was obtained. In 2020, Baran [ 13] studied the effect of temperature and light intensity on the conversion efficiency of Ge-based solar cells.

What is the VOC of germanium-based solar cells?

The VOC of the germanium-based solar cells under the single-junction CC nanostructure absorber structure array is 0.31 V, and the JSC reaches 45.5 mA/cm 2. The FF value of the device can be calculated as 72.7% by Equation (4). The η of the device of 10.3% can be reached by Equation (5).

Can cross-cone nanostructure improve the absorption rate of germanium-based solar cells?

In this work, we designed the cross-cone nanostructure as the absorption layer of germanium-based solar cells, which can increase the optical path of light transmission in the absorption layer and improve the absorption rate of the whole band and the Ge materials as the absorption layer can broaden the absorption band.

Why is germanium a promising material?

Investigation of the ultrafast photoexcited electronic response in semiconductors has provided invaluable insights into the carrier dynamics and dielectric properties of many materials. Germanium and its alloys with Si have promise for creating mid-infrared optoelectronics 1 and multijunction solar cells with higher efficiency 2.