Yang and his team followed the natural processes in the leaf of a plant to build the postage stamp-sized device that mimics the way green plants harvest energy from the sun. However, instead of chlorophyll – a natural compound found in green plants that gives them their color and plays a key role in the process of photosynthesis – the scientists used lead halide perovskite photoabsorbers to capture sunlight.

These were paired with finely engineered copper electrocatalysts – designed to resemble tiny flowers – to drive chemical reactions. The electrocatalysts were reportedly inspired by enzymes that regulate photosynthesis in nature. Yang explained how each individual component of a leaf’s photosynthesizing elements had to be carefully replicated and refined.