* Corresponding authors

a College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, P. R. China E-mail: [email protected], [email protected]

b School of Chemical Sciences, The University of Auckland, Auckland 1142, New Zealand

c College of Materials Science and Engineering, Changsha University of Science & Technology, Changsha 410114, P. R. China

d MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand