Publication reports an innovative method for buffer layer production for photovoltaic (PV) cells. EPSRC funded project. ZnS deposition is an alternative to toxic cadmium containing CdS layers. The environmental impact is minimised by replacing the complexing agent, hydrazine hydrate, with sodium citrate. Relevant and addresses need to minimise the environmental impact in a rapidly expanding industry. This work was an outcome of a project judged to be “tending to outstanding” by reviewers (GR/N04645/01. The work is a foundation for future NPAC research.