Most forms of plastic packaging — water bottles, pill bubbles, sealed clamshells that require sweat and blood to pry into — do their jobs just fine, or almost too well.

But for highly moisture-sensitive products, the average plastic isn’t enough. Water vapor can still get in through microscopic pores in the plastic. If medicines or electronics were better protected from water, they’d have a longer shelf life.

Scientists developed packaging that involves a single-atom layer of graphene on flexible polymer films to keep moisture out, according to the American Chemical Society.

They tested it on an organic photovoltaic device, a technology that can be used to capture solar energy in a flexible, low-cost form. The new packaging gave the device a lifetime of more than a year, compared to 30 minutes using graphene-free polymer before water destroyed it.

How to package such light- and moisture-sensitive solar cells is a problem scientists continue to work through, by experimenting with humidity and new methods to encase cells without getting too clunky. The graphene polymer discovery could bring renewable energy closer faster.