Erratum to: Polypyrrole@NiCo hybrid nanotube arrays as high performance electrocatalyst for hydrogen evolution reaction in alkaline solution

Figure 2(b) on Page 476: It has come to our attention that the data of (i) Co NTAs in Fig. 2(b) is not correct, because we imported the same group of data of PPy@NiCo HNTAs accidentally while plotting with Origin. The corrected Fig. 2(b) is shown below. The data analysis and conclusions are not affected by this unintentional error.