Scientific Reports 5: Article number: 7717; published online: 12 January 2015; updated: 03 August 2015

In the original version of the Article, the first affiliation ‘Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, Gyeongbuk, Republic of Korea’ was omitted for author Gyoo Yeol Jung.

In addition, Anthony K. Au and Albert Folch were omitted from the author list.

The Author Contributions section now reads:

W.L. designed, carried out the experiments, collected and analyzed the data and wrote the manuscript; D.K. and W.C. helped with experiments and data analysis; G.Y.J. helped with data analysis; A.K.A. and A.F. helped with device design, S.J. conceived the experiments, analyzed results and wrote the manuscript.

These have now been corrected in both the HTML and PDF versions of the Article.