Researchers have developed a new water sensor that operates on energy generated by ocean waves to detect various pollutants, eliminating the need for batteries.

Access to clean water is vital for health, but maintaining its purity is difficult in areas that are either polluted or hard to reach. This innovative sensor is small and energy-efficient, relying solely on the movement of waves for power.

The device features two main elements. First, it includes a special energy harvester called a rotational triboelectric nanogenerator (R-TENG), which converts wave motion into electricity.

This generated power then drives a highly sensitive sensor, built with robust materials like AlGaN/GaN, that can withstand challenging environments. The findings of this study were published in the journal Nano Energy.

The sensor is proficient at detecting harmful elements, such as heavy metals like lead, arsenic, and chromium, as well as pesticides and tiny plastic particles.

Housed in a waterproof shell and operated by magnets, the device can function continuously underwater. It generates a reliable voltage, even in humid conditions, charging a small capacitor in approximately 10 seconds, which provides power for real-time measurements.

In laboratory and river tests, the sensor showed impressive accuracy, capable of identifying pollutants at very low concentrations while responding effectively to changes in water acidity.

This battery-free design not only simplifies installation but also extends the sensor’s operational lifespan in oceans, rivers, and lakes. This advancement supports environmental conservation and promotes public health.

“Our compact, self-sufficient sensor is an excellent solution for monitoring water quality in remote areas and for early detection of pollution,” states Prof. Zong-Hong Lin.