Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2015 Nov 27:5:17371.
doi: 10.1038/srep17371.

High Efficiency Organic/Silicon-Nanowire Hybrid Solar Cells: Significance of Strong Inversion Layer

Xuegong Yu  1 , Xinlei Shen  1 , Xinhui Mu  1 , Jie Zhang  2 , Baoquan Sun  2 , Lingsheng Zeng  1 , Lifei Yang  1 , Yichao Wu  1 , Hang He  1 , Deren Yang  1
Affiliations

High Efficiency Organic/Silicon-Nanowire Hybrid Solar Cells: Significance of Strong Inversion Layer

Xuegong Yu et al. Sci Rep. .

Abstract

Organic/silicon nanowires (SiNWs) hybrid solar cells have recently been recognized as one of potentially low-cost candidates for photovoltaic application. Here, we have controllably prepared a series of uniform silicon nanowires (SiNWs) with various diameters on silicon substrate by metal-assisted chemical etching followed by thermal oxidization, and then fabricated the organic/SiNWs hybrid solar cells with poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (

Pedot: PSS). It is found that the reflective index of SiNWs layer for sunlight depends on the filling ratio of SiNWs. Compared to the SiNWs with the lowest reflectivity (LR-SiNWs), the solar cell based on the SiNWs with low filling ratio (LF-SiNWs) has a higher open-circuit voltage and fill factor. The capacitance-voltage measurements have clarified that the built-in potential barrier at the LF-SiNWs/

Pedot: PSS interface is much larger than that at the LR-SiNWs/PEDOT one, which yields a strong inversion layer generating near the silicon surface. The formation of inversion layer can effectively suppress the carrier recombination, reducing the leakage current of solar cell, and meanwhile transfer the LF-SiNWs/

Pedot: PSS device into a p-n junction. As a result, a highest efficiency of 13.11% is achieved for the LF-SiNWs/

Pedot: PSS solar cell. These results pave a way to the fabrication of high efficiency organic/SiNWs hybrid solar cells.

PubMed Disclaimer

Figures

Figure 1
Figure 1
(a,b) SEM images of a Au-coated AAO membrane and a Au mesh-coated silicon wafer, respectively; (c) SEM image of SiNWs; (d) TEM diagram of an individual SiNW; (e) HRTEM diagram of a SiNW; (f) Histogram of the SiNWs diameter distribution, together with a Gaussian fit (solid line) of the measured statistical data.
Figure 2
Figure 2. SEM images of the SiNWs obtained by varying the thermal oxidation time.
(a) 0 min; (b) 45 min; (c) 90 min; (d) 180 min; (c) 300 min; (d) 600 min.
Figure 3
Figure 3. Reflectance of SiNWs subjected to thermal oxidation for different time followed by HF acid etching.
Figure 4
Figure 4. The reflectance of planar-Si/PEDOT:PSS, LF-SiNWs/PEDOT:PSS and LR-SiNWs/PEDOT:PSS samples.
Figure 5
Figure 5
(a) Illuminated J-V characteristics and (b) EQEs of planar-Si/PEDOT:PSS, LF-SiNWs/PEDOT:PSS and LR-SiNWs/PEDOT: PSS solar cells.
Figure 6
Figure 6. SEM cross-sectional micrographs of various SiNWs/PEDOT:PSS samples.
Figure 7
Figure 7. 1/C2-V plots of the Planar-Si/PEDOT:PSS, LR-SiNWs/PEDOT:PSS and LF-SiNWs/PEDOT:PSS hybrid solar cells.
Figure 8
Figure 8
The density of interface states (DOS) and energy band diagram near the silicon surface in the (a) Planar-Si/PEDOT:PSS, (b) LR-SiNWs/PEDOT:PSS and (c) LF-SiNWs/PEDOT:PSS hybrid solar cells.
Figure 9
Figure 9
Mapping of the carrier lifetime of (a) planar-Si, (b) LR-SiNWs, (c) LF-SiNWs samples, and mapping of the carrier lifetime of (d) planar-Si, (e) LR-SiNWs, (f) LF-SiNWs samples after spin-coating of PEDOT:PSS films.
Figure 10
Figure 10. Current density versus voltage characteristic of the Planar-Si/PEDOT:PSS, LR-SiNWs/PEDOT:PSS and LF-SiNWs/PEDOT:PSS hybrid solar cells.
Figure 11
Figure 11
(a) The temperature dependent dark I−V characteristic and (b) n × ln(J0) versus 1/T characteristics of a LF-SiNWs/PEDOT:PSS solar cell yielding an activation energy barrier of ~1.12 eV.
See this image and copyright information in PMC

References

    1. Service R. F. Solar energy. Can the upstarts top silicon ? Science (New York, NY) 319, 718 (2008). - PubMed
    1. Grätzel M. Photoelectrochemical cells. Nature 414, 338–344 (2001). - PubMed
    1. Li G., Zhu R. & Yang Y. Polymer solar cells. Nat. Photon. 6, 153–161 (2012).
    1. Jeong H. et al. Enhanced light absorption of silicon nanotube arrays for organic/inorganic hybrid solar cells. Adv. Mater. 26, 3445–3450 (2014). - PubMed
    1. Ahlstrom E. & Gärtner W. Silicon Surface-Barrier Photocells. J. Appl. Phys. 33, 2602–2606 (1962).

Publication types