Kappera, Rajesh
Voiry, Damien
Yalcin, Sibel Ebru
Branch, Brittany
Gupta, Gautam
Mohite, Aditya D.
Chhowalla, Manish
Article History
Received: 21 April 2014
Accepted: 2 August 2014
First Online: 31 August 2014
Change Date: 12 September 2014
Change Type: Correction
Change Details: In the version of this Article originally published online, for Fig. 1c, the size given for the scale bar was incorrect; it should have been '5 nm'. This error has now been corrected in all versions of the Article.
Competing interests
: The authors declare no competing financial interests.