Epicuticular electrification: spontaneous charging of materials at the world's largest bio-air interface

The materials on the outer plant surface create the world's largest bio-air interface. Invisibly, this surface spontaneously charges when hit by raindrops and solid materials. This is due to contact electrification, a phenomenon used in technologies like printing and energy harvesting. Yet, extraordinarily little is known about its role in nature and how biosurfaces charge.

EpiC will target two exciting and unresolved questions: a) can one exploit the generated charges to power high-tech devices at the leaf-air interface? and b) how is the organism affected by the electric fields generated on the outer leaf surface?

The core of EpiC is thus a detailed surface analysis to gain the highest resolved insights in solid and liquid contact electrification of biosurfaces.

To achieve this, I will combine studies of materials surface charging, chemical, and topographical analyses with observations of cellular responses, plant growth, and adaptation.This data set will then indicate how to engineer material systems named 'artificial leaves' that can be installed on the plant leaf or sprayed on it to harvest the contact charges for technical purposes.

EpiC will eventually enable energy harvesting, environmental and plant health sensing, communication with robots, and electrocatalytic reactions - autonomously driven by electricity and reactants from the leaf environment.

Moreover, I will develop additional features in the materials of the artificial leaf to specifically protect the plant and to boost its growth during energy harvesting.The result of EpiC will be new insights into contact charging of materials in nature, its effect on plant life, and a ground-breaking, energy-autonomous, and sustainable technology platform for the world's most significant bio-air interface with cross-disciplinary impact in materials science, environmental sensing and robotics, smarter agriculture, and plant-based bioelectrochemical systems.