Figure 4.

Electrical performance of paper electrode. a) Mass loadings of polypyrrole (▪), sheet resistance (•) and conductivity (▴) of the fabricated polypyrrole‐coated paper with respect to polymerization time of 5, 20, 60 and 180 minutes. b) Polypyrrole‐coated paper as electrical connections to light a blue LED by a homemade 2.7 V battery. c) Current‐time curves of polypyrrole‐coated paper bent with different curvatures under a constant voltage. The upper insets labeled I, II, III, IV and V reveal the five bending states. The lower left inset shows the current‐voltage curve of polypyrrole‐coated paper without bending. The lower right inset records the current‐voltage curves of polypyrrole‐coated paper after 20, 50, 80 and 100 cycles of bending. Reproduced with permission.12 Copyright 2013, Royal Society of Chemistry.