The CAs of thylakoid membrane modified GE/P(DTP-Ph-NH2)/Cyt C electrodes, with different cyclic voltammetry cycles (a) 20, (b) 30, (c) 40, (d) 50, (e) 60, (f) 70, (g) 80 applied for the Cyt C, in 10mM pH 7.4 PBS upon on-off illumination of visible light at an intensity of 6800 W/m2, applied potential; 0V (vs Ag/AgCl).