Self-powered nanosensors for wearable health monitoring

Researchers at the University of Surrey have developed battery-free nanosensors that generate their own power from small body movements. The technology could support next-generation wearable devices for sleep monitoring, home healthcare and dementia care, according to a study published in Advanced Materials.

Wearable health technologies such as smartwatches typically rely on batteries and regular charging, which can limit continuous monitoring and long-term usability. Researchers at the University of Surrey’s Advanced Technology Institute (ATI) have now developed battery-free nanosensors designed to operate without wires or external power sources.

The technology takes the form of a soft sensor mat that can be integrated into clothing or next-generation wearable systems. Instead of relying on batteries, the sensors harvest energy from small human movements, including breathing, walking or turning during sleep.

According to the research team, the concept could enable more comfortable and less obtrusive health monitoring, particularly in home-care settings.

To test the technology, the researchers built a system consisting of 16 nanosensors capable of detecting subtle pressure changes. In experiments, the sensor array successfully captured different sleep patterns and body movements.

These capabilities suggest potential applications in:

• sleep disorder monitoring
• dementia care and patient observation
• long-term health monitoring at home
• next-generation wearable healthcare devices

Sajib Roy, Postgraduate Researcher at Surrey’s Advanced Technology Institute and lead author of the study, explains: "The key achievement of our work is that the sensor is extremely sensitive to very small movements while powering itself at the same time. The device can detect very subtle human motions while simultaneously generating enough power to operate low-power electronics, even from gentle movement, enabling truly continuous, maintenance-free sensing."

The study, published in Advanced Materials, describes one of the most sensitive self-powered pressure sensors reported for low-frequency human motion.

The device is built from an ultra-thin nanofiber structure produced through an electrospinning process. In this structure, researchers embedded borophene, a two-dimensional boron-based nanomaterial, into a flexible polymer matrix.

When pressure or motion is applied to the material, it generates an electrical signal. This eliminates the need for batteries and allows the device to power low-energy electronics directly.

The researchers say the resulting electrical signals are strong enough to support continuous sensing systems, opening potential applications in wearable technologies, healthcare monitoring and smart environments.

Professor Ravi Silva, Director of Surrey’s Advanced Technology Institute and Interim Director of the Institute for Sustainability, highlights the broader relevance of the research: "We have shown how advances in materials science can be translated into practical and impactful healthcare technologies. Battery-free and unobtrusive monitoring systems like this have significant potential to support continuous health monitoring and the next generation of digital healthcare solutions, particularly for home-based care. This is exactly the type of development needed for enabling SDG-3 for good health and wellbeing in society."

The work also supports the development strategy of Z-PULSE, a spin-out company from the University of Surrey focusing on advanced materials for healthcare monitoring technologies.

Bhaskar Dudem, CTO and Co-founder of Z-PULSE Ltd, says: "This work shows the promise of nanofiber-based, self-powered sensors for unobtrusive sleep assessment. For dementia care in particular, the ability to monitor movement comfortably and continuously – without wearables or batteries – could make a real difference, and we are excited to progress toward real-time clinical studies."

COMPAMED-tradefair.com; Source: University of Surrey