Fig. 4
Switchable photoresistors to determine PV device degradation. a Diagram illustrating switchable photoresistors. b, c Current as a function of time for 20 cycles of 3-min illumination followed by 5 min of cooling in the dark for a photoresistor in the presence of 0 Torr (b) and 11 Torr (c) partial pressure of CH3NH2 gas. Photoresistors were operated at a constant voltage of 0.65 V, which corresponds to the maximum power point voltage of the highest performing switchable PV devices. d, e Optical photographs of the photoresistor channel after 20 switching cycles in the presence of 0 Torr (d) and 11 Torr (e) partial pressure of CH3NH2 gas. Scale bars are 25 μm
