Scientists Develop Solar Cell Polymer With Double Charge Production

Scientists from the U.S. Department of Energy's Brookhaven National Laboratory and Columbia University have developed a solar cell polymer that doubles its electrical charge carrier per unit of light from one carrier to two.

The process of producing two producing two charges from one unit of light is called singlet fission. This discovery can alter the manufacturing process of solar energy producing materials. Having two charges on the same molecule mans that energy-producing materials don't have to be arrayed as perfect crystals. The self-contained materials work efficiently when dissolved in liquids which opens up new ways to develop solar cells including "printing" solar-energy-producing material like ink.

A polymer is a combination of chemical compounds that is made up of repeating structural units (as in a molecular structure). The structure of the polymer dictates it properties.

Polymers are usually associated with plastics. The material used for credit cards is a polymer, as well as PVC plastics and PET water bottles. But polymers can be in any form. Hairspray and mousse is a polymer. Fabrics like spandex are also polymers. While these are synthetic, there are also natural polymers like rubber and amber.

The image above shows Postdoctoral fellow Erik Busby and Matt Sfeir with optical equipment they used to study charge carrier production in organic photovoltaic polymers at Brookhaven Lab's Center for Functional Nanomaterials.

New Process in Manufacturing Denim Jeans More Economical, Efficient, and Environment Friendly

Jeans are pants that are made from denim. Although in popular culture, these are referred to as denim jeans, blue jeans, or just jeans.

Denim jeans are identified with American culture especially the cowboy westerns. This is because jeans were popularized as work trousers during the California gold rush when Levi Strauss introduced them with copper rivets. The rivets served a purpose in that it made jeans more durable, giving more sturdiness at stress points such as pocket corners.

The denim cloth gets its name from the city of Nimes in France (de Nimes). It is a rugged cotton twill textile. One particular feature of denim is that it fades over time. In denim jeans, fading occurs at stress areas such as the upper thighs, the knees, and ankles. People tend to favor this and it is not peculiar to see new jeans that have undergone processes to make it look old,used, and/or faded.

Now, denim jeans are available in most any color. But it is primarily known for being dyed blue using Indigo. Indigo is a natural dye extracted from plants with a distinctive blue color. The cotton fibers in denim were difficult to dye using other dyes, so traditionally Indigo became the primary dye used for cotton. Today, almost all indigo dye used in manufacturing is synthetic. The few companies using natural indigo charge a premium for their product because of this.

Sustainable denim manufacturing process creates 'green' jeans

Some estimates suggest that producing one pair of jeans requires more than 2,500 gallons of water, nearly a pound of chemicals and vast amounts of energy. Multiply that by 2 billion — the number of jeans produced worldwide every year — and you get a snapshot of an industry that contributes a hefty share of wastewater and greenhouse gases to the environment.

But an emerging greener chemistry process, described at the 16th annual Green Chemistry & Engineering Conference, could help change all of that. The conference is sponsored by the American Chemical Society's Green Chemistry Institute® (ACS GCI).

The process, called Advanced Denim, can produce a pair of jeans using up to 92 percent less water and up to 30 percent less energy than conventional denim manufacturing methods, according to Miguel Sanchez, a textile engineer at Clariant, a specialty chemical company based in Muttenz (near Basel), Switzerland, that developed Advanced Denim. In addition, it generates up to 87 percent less cotton waste (which is often burned, adding carbon dioxide and other greenhouse gases to the atmosphere) and virtually no wastewater.