Scientific Reports 6: Article number: 21694; Published online: 15 February 2016; Updated: 09 May 2016

The original version of this Article incorrectly listed ‘College of Chemistry and Environment, Minnan Normal University, Zhangzhou, China, 363000’ as a present address for Bang-Qin Huang rather than Shun-Xing Li.

This error has now been corrected in the PDF and HTML versions of the Article.