Ultra-thin device, help pedestrians fully charge the phone battery

With a thickness of only 1/5000 times a hair, the new device can extract energy even when we move very gently and slowly.

Scientists at Vanderbilt University in the United States have created a material that collects extremely small amounts of energy that can extract energy from human movement .

Products can be placed in clothing layers to recharge when we move daily. The amount of electricity collected can be used to charge smartphones, tablets or other personal electronic devices.

This new device exploits excess energy from human movement.(Photo: Shutterstock).

Cary Pint, a project researcher, said: "In the future, I hope that all of us will recharge our personal devices by charging energy directly while on the move. '.

Previously, there were many studies conducted to harvest the available energy sources such as extracting energy from vibration and distortion; pulling energy from temperature changes, or collecting energy from light, radio waves and other forms of radiation .

However, a high-value energy source has been overlooked, which is the excess energy from human movement. Although some scientists have created a number of materials, they can only work well with frequencies more than 100 times per second, most of the movement of ordinary people cannot reach this speed. .

With a thickness of only 1/5000 times a hair, the new device can extract energy even when we move very gently and slowly.

"When compared to other materials, this material possesses two basic advantages: one is thickness, two are sensitivity, " Pint said, "This material is so thin and small that it can be attached to layers. Only without affecting the feel of the fabric, notably, it can take energy from movements that are slower than 10 Hertz (10 times / second), corresponding to human movement ".

In the study, scientists used graphene and two layers of black phosphorus - a material that is always attractive to nanotechnologists because of its electrochemical and electrochemical properties.

The energy harvester is created by introducing graphene (an electrolyte) between two identical black phosphorus electrodes. The electrodes are produced through the chemical process when the black phosphorus layer interacts with the electrolyte.

Combined, 2D materials have the ability to bend and create energy.

Researchers are testing on a sample product.(Photo: Vanderbilt University).

The group's prototype design can generate energy from movements of less than 10 Hertz (10 motions per second) and even 0.01 hertz (1 motion per 100 seconds).

When asked about the safety of materials, Pint is confident that users will never see the device short-circuited, leading to fire and explosion like many other electrical products.

Pint added: 'The batteries are often burned when the positive and negative electrodes are consumed; In this new material, because there are two identical electrodes, the process of consumption only affects the ability to produce electricity '.

In the future, the group will continue to improve to increase the ability to extract electricity from the device because at the present time, the new device obtains a relatively low voltage within the millivolt range (mV).

2D material is a layer of nanomaterials just a few atoms thick. The electrons in this material are free to move in the two-dimensional plane, but their limited motion is governed by quantum mechanics.

Research on 2D nanomaterials is still in the early stages, but 2D materials such as graphene, transition metal dichalcogenide and black phosphorus have attracted the attention of scientists because they have different properties and ability to improve optoelectronic devices.