Virus-templated self-assembled single-walled carbon nanotubes for highly efficient electron collection in photovoltaic devices


The performance of photovoltaic devices could be improved by using rationally designed nanocomposites with high electron mobility to efficiently collect photo-generated electrons. Single-walled carbon nanotubes exhibit very high electron mobility, but the incorporation of such nanotubes into nanocomposites to create efficient photovoltaic devices is challenging. Here, we report the synthesis of single-walled carbon nanotube–TiO2 nanocrystal core–shell nanocomposites using a genetically engineered M13 virus as a template. By using the nanocomposites as photoanodes in dye-sensitized solar cells, we demonstrate that even small fractions of nanotubes improve the power conversion efficiency by increasing the electron collection efficiency. We also show that both the electronic type and degree of bundling of the nanotubes in the nanotube/TiO2 complex are critical factors in determining device performance. With our approach, we achieve a power conversion efficiency in the dye-sensitized solar cells of 10.6%.

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Figure 1: Schematic diagram of virus-enabled SWNT/TiO2 DSSCs.
Figure 2: Characterization of the virus/SWNT complex and biomineralization of TiO2 on the virus/SWNT complex.
Figure 3: Device performance and characterization.
Figure 4: Effect of bundling of SWNTs in virus/SWNT complexes on device performance.
Figure 5: Device performance of the best DSSC in this study.


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This work was supported by Eni, S.p.A (Italy) through the MIT Energy Initiative Program. H.Y. is grateful for a Korean Government Overseas Scholarship. R.L. is grateful for a National Science Foundation Graduate Research Fellowship.

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X.D., H.Y., P.T.H. and A.M.B. conceived the idea and designed the experiments. X.D., H.Y., M.H.H., J.Q., D.S.Y., R.L. and M.S.S. performed the experiments and analysed the data. X.D., H.Y., P.T.H. and A.M.B. co-wrote the paper and all authors discussed the results and commented on the manuscript.

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Correspondence to Paula T. Hammond or Angela M. Belcher.

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The authors declare no competing financial interests.

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Dang, X., Yi, H., Ham, M. et al. Virus-templated self-assembled single-walled carbon nanotubes for highly efficient electron collection in photovoltaic devices. Nature Nanotech 6, 377–384 (2011).

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