Thin film encapsulation of DSSCs on plastic substrate

Aluminum oxynitride (AlOxNy) films were deposited on polyethylene naphthalate (PEN) substrates using a reactive radio frequency (RF) magnetron sputtering system by varying the nitrogen flow rate. Experimental results show that the AlOxNy films deposited on PEN substrate exhibit a pebble-like surface morphology. The deposition rate decreases slightly upon increasing the nitrogen flow rate. The surface roughness of the deposited AlOxNy films also decreases upon increasing the nitrogen flow rate. The AlOxNy film deposited at a nitrogen flow rate of 15 sccm exhibited the lowest water vapor transmission rate of 0.02 g/m2·day. Meanwhile, the passivation of AlOxNy films can effectively improve the long-term stability of plastic DSSC. Their power conversion efficiency can sustain 50% of the initial values even after 300 h.