Water based spray pyrolysis of metal-oxide solutions for Cu2ZnSn(S,Se)4 solar cells using low toxicity amine/thiol complexants
journal contributionposted on 06.12.2018 by Lewis Wright, Jamie Lowe, Martin Bliss, Vincent Tsai, Mustafa Togay, Tom Betts, Michael Walls, Andrei Malkov, Jake Bowers
Any type of content formally published in an academic journal, usually following a peer-review process.
Cu ZnSnS(e) 2 4 deposited using solution processes has potential for terrawatt-scale deployment. The champion highest efficiency Cu ZnSn(S,Se) 2 4 cell published in literature is spin-coated using the highly dangerous hydrazine which is an impractically scalable solvent and deposition combination. As an alternative solvent amine-thiol mixtures have shown to complex with a wide range of binary chalcogenides with much lower health risks than hydrazine. Herein we present two further toxicity reductions, first by employing a less harmful amine-thiol pairing and second by using water as a diluting solvent. We exclude extraneous elements from the precursor solution such as halogens and with a sub-micron thickness crystalline absorber achieve an efficiency of 6.8 %. With the modified solution deposited by ultrasonic spray pyrolysis, this solution process is scalable, abundant, and relatively non-toxic.
The authors would like to acknowledge the EPSRC for funding through the Centre for Doctoral Training in New and Sustainable Photovoltaics [grant number EP/L01551X/1] and The PVTEAM project [grant number EP/L017792/1] to support this work.