graphene

A New “Wonder Material” | Earth Wise

February 11, 2022 By EarthWise Leave a Comment

Graphene is a form of carbon made of single-atom-thick layers. It has many remarkable properties and researchers around the world continue to investigate its use in multiple applications.

In 2019, a new material composed of single-atom-thick layers was produced for the first time. It is phosphorene nanoribbons or PNRs, which are ribbon-like strands of two-dimensional phosphorous. These materials are tiny ribbons that can be a single atomic layer thick and less than 100 atoms wide but millions of atoms long. They are comparable in aspect ratio to the cables that span the Golden Gate Bridge. Theoretical studies have predicted how PNR properties could benefit all sorts of devices, including batteries, biomedical sensors, thermoelectric devices, nanoelectronics, and quantum computers.

As an example, nanoribbons have great potential to create faster-charging batteries because they can hold more ions than can be stored in conventional battery materials.

Recently, for the first time, a team of researchers led by Imperial College London and University College London researchers has used PNRs to significantly improve the efficiency of a device. The device is a new kind of solar cell, and it represents the first demonstration that this new wonder material might actually live up to its hype.

The researchers incorporated PNRs into solar cells made from perovskites. The resultant devices had an efficiency above 21%, which is comparable to traditional silicon solar cells. Apart from the measured results, the team was able to experimentally verify the mechanism by which the PNRs enhanced the improved efficiency.

Further studies using PNRs in devices will allow researchers to discover more mechanisms for how they can improve performance.

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‘Wonder material’ phosphorene nanoribbons live up to hype in first demonstration

Photo, posted October 6, 2010, courtesy of Alexander AlUS / CORE-Materials via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

New Membranes For Carbon Capture

October 2, 2019 By EarthWise Leave a Comment

Drastically reducing the amount of carbon dioxide being emitted into the atmosphere is an essential goal in the effort to mitigate the effects of climate change. While the ultimate solution is to avoid combustion of fossil fuels by the use of clean alternative energy sources, that transition will take time – possibly more time than we have. As a result, there is a great deal of effort underway to develop techniques for capturing the carbon emitted by fossil fuel combustion and either recycling it or storing it.

There are multiple ways to capture carbon emissions, but the ultimate goal is to find a technique that is both inexpensive and scalable. One promising technique involves the use of high-performance membranes, which are filters that can specifically pick out CO2 from a mix of gases, such as those coming out of a factory smokestack.

Scientists at a Swiss laboratory have now developed a new class of high-performance membranes that exceeds the targeted performance for carbon capture by a significant margin. The membranes are based on single-layer graphene with a selective layer thinner than 20 nanometers – only about 40 atoms thick. The membranes are highly tunable in terms of chemistry, meaning that they can be designed to capture specific molecules.

The membranes are highly permeable – meaning that they don’t impede gas flow too much – but highly selective. The CO2/N2 separation factor is 22.5, which means that 22.5 times more nitrogen can get through the membrane than carbon dioxide.

The work is just at the laboratory stage at this point, but it is a very promising step towards developing a practical scheme for keeping carbon dioxide from escaping from power-plant and factory smokestacks.

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Next-gen membranes for carbon capture

Photo, posted December 28, 2010, courtesy of Emilian Robert Vicol via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Electricity From A Bionic Mushroom

December 28, 2018 By EarthWise Leave a Comment

In an engineering feat straight out of a weird science-fiction story, researchers at Stevens Institute of Technology in New Jersey have taken an ordinary white button mushroom and used 3D printing technology to coat it with graphene microribbons and cyanobacteria to produce a device that generates electricity.

Fern-Inspired Energy Storage

July 5, 2017 By EarthWise

The amount of solar energy striking the surface of the earth in two hours is enough to supply all of humankind’s needs for an entire year. For this reason, it is widely thought that solar energy should be our primary source of electricity. If this is to happen, however, there must be cost-effective ways to obtain solar electricity regardless of the time of day, weather, or seasonal changes. Essentially, there must be ways to store the energy from the sun to use it when we need it.

Turning Seawater Into Drinking Water

May 10, 2017 By EarthWise

Graphene is often called the wonder material. First isolated by scientists in 2004, it is a form of carbon that is just one atom thick, extremely light, two hundred times stronger than steel, highly flexible, and an excellent conductor of heat and electricity. Scientists are finding numerous applications for it.

Recycled Plastic Lumber

July 20, 2016 By WAMC WEB

One of the most notable success stories in recycling is that of structural plastic lumber. The material is mostly polyethylene reinforced with stiff plastics or recycled composites. Made from milk containers, coffee cups, and other recycled plastics, structural plastic lumber is lighter than steel, longer-lasting than natural lumber and strong enough to support 120-ton locomotives.

Ever-Changing Light Bulbs

August 6, 2015 By EarthWise

Electric light became a part of our lives around 1880 as Thomas Edison began illuminating parts of New York City. For more than 100 years, the basic operating principle of light bulbs remained the same. For the most part, we used the incandescent bulbs that Edison pioneered. Of course, there were fluorescent bulbs as well, but most of our lamps used the familiar incandescent in various configurations.