Innovative Paper-Based Device Harvests Power From Ambient Moisture

A team at Binghamton University has unveiled a paper-based device capable of generating electricity from moisture in the air. This breakthrough could transform the power source for wearable electronics and other low-power applications.

In a world where wearable electronics are becoming increasingly common, especially in health care, the challenge of efficient and sustainable power sources persists. Traditional batteries are rigid and often have short lifespans, while wireless power transfer offers limited range and portability.

Seokheun “Sean” Choi, a professor at Binghamton University, together with Anwar Elhadad, an assistant professor of electrical and computer engineering, and Yang “Lexi” Gao, a doctoral student in Choi’s lab, have developed an innovative approach to tackle this issue. The team has created a paper-based wearable device that can efficiently capture and convert moisture from the air into electricity.

“Wearable electronics will use energy-harvesting techniques in the future, but right now, the techniques are very irregular in time, random in location and inefficiently converted,” Choi said in a news release. “The reason why I was interested in this topic is that the moisture in our air is ubiquitous, and I realized that energy harvesting from moisture is very easy.”

In a recent paper published in the journal Small, the team detailed the workings of their device. The generator leverages bacterial spores as the functional group to break down water molecules into ions. The paper’s natural capillaries absorb these spores, creating a gradient with more positive ions on top than on the bottom, producing an electric charge.

The device’s efficiency is enhanced by a Janus paper layer, which is hydrophobic on one side and hydrophilic on the other, optimizing moisture absorption and retention until processed.

This breakthrough is an extension of Choi’s 15 years of research in biobatteries and his vision for “papertronics” — electronics made entirely from paper, which are flexible, wearable, scalable and environmentally friendly. The moist-electric generator could revolutionize low-power sensors, drug delivery systems and electrical stimulation applications.

Potential enhancements to this technology include boosting its power output, finding methods for energy storage and integrating with other energy-harvesting technologies. Choi also aims to miniaturize the device to the scale of micro-electromechanical systems (MEMS).

“By decreasing each individual unit and connecting more cells within a small footprint, we can improve the power density significantly,” added Choi. “Also, because we are using paper, we can try many other ideas, including origami techniques.”

While many focus on long-term wearable devices, Choi advocates for disposable solutions to prevent electronic waste.

“I don’t want to wear something all day for four months. I want to use it for a short time and then throw it away — so in that way, paper is the best,” he added.

The implications of such a device are vast, promising more sustainable, flexible and efficient power solutions for various applications, potentially transforming the landscape of wearable electronics and other low-power devices.