The manufacture of perovskite solar cells can now be scaled up with a roll-to-roll printing process using a low-cost carbon ink formulation for effective coating of conductive electrode layers.

The slot die coating process incorporated into the roll-to-roll technology devised at Swansea University’s Sustainable Product Engineering Centre for Innovative Functional Industrial Coatings (SPECIFIC) Innovation and Knowledge Centre substitutes carbon electrode ink for the more costly and commonly used gold electrodes.

Perovskite cells equipped with carbon electrodes were demonstrated to provide a similar photovoltaic performance to the conventional evaporated gold electrodes as part of a small-scale device on a rigid glass substrate. The research reported in Advanced Materials also confirms power conversion efficiencies of up to 14% and enhanced long-term stability.

A device printed onto a 20 m long flexible substrate retained 84% of its original efficiency over 1,000 hours under 70% relative humidity and 25° C.