Sound Waves Create Plant Sunscreen in RMIT Breakthrough

Scientists at RMIT University have cracked a manufacturing puzzle that's stumped researchers for years: how to coat delicate surfaces without damaging them in the process.

Their solution sounds like science fiction. High-frequency sound waves create a protective mist that forms into a UV-blocking coating at room temperature, gentle enough to apply directly onto living plant leaves without harming a single cell.

The researchers tested their invention by giving plants their own sunscreen. The coating absorbed harmful ultraviolet light while letting through the visible light plants need for photosynthesis. Treated leaves grew normally for months afterward, proving the process caused zero damage.

Lead author Javad Khosravi Farsani explained the dual benefit. "The coating absorbs harmful UV light while allowing visible light through. That means the plant can continue photosynthesis while being protected from damage."

The magic happens through vibrations that break liquid into microscopic droplets. As these droplets float through the air, they organize themselves into a solid protective layer before landing on the target surface. The entire process takes just minutes and requires no heat, harsh chemicals, or specialized equipment.

The Ripple Effect

This breakthrough solves a problem that extends far beyond agriculture. Conventional coating methods rely on ovens, aggressive solvents, or equipment that destroys fragile materials. That's forced manufacturers to choose between protecting surfaces and preserving the quality of protective materials themselves.

Senior author Leslie Yeo highlighted the widespread impact. "These materials have extraordinary properties, but you've typically had to choose between preserving their structure and protecting the surface you're applying them to. What this work shows is a way to avoid that trade-off."

The coating material comes from covalent organic frameworks, a class of porous materials prized for their ability to absorb light, separate molecules, and protect surfaces. Industries handling sensitive electronics, sensors, and membranes have struggled for years to apply these materials without causing damage.

Co-author Joseph Richardson emphasized the simplicity. "Our method effectively combines manufacturing and coating into a single step. That simplicity is what makes it adaptable across different surfaces and applications."

RMIT filed a provisional patent for the technology earlier this year. The research team included collaborators from across Australia and Europe, including Spain's Catalan Institute of Nanoscience and Nanotechnology.

The study appeared in the journal Science Advances, marking a potential turning point for industries that work with heat-sensitive or chemically reactive materials.

From protecting crops against intensifying UV radiation to coating next-generation electronics, this sound wave technique opens doors that traditional manufacturing methods kept firmly closed.