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One of the most important catalysts in the modern chemical industry is a troublemaker. The building blocks of zeolite ZSM-5 crystals, which are a sort of Swiss cheese with molecular size holes, are not joined together perfectly. The materials that have to pass through the crystals therefore often get stuck and don’t react well. Dutch researcher Marianne Kox discovered the deviations in the miniscule but indispensable particles.

Nearly all medicines, fuels and other chemical products come into contact with catalysts at some stage of their ‘lives’. These help to convert one material, for instance crude oil, into another, such as petrol. Take a good look around and you can see the evidence of the hard work done by these catalyst particles everywhere. Marianne Kox studied one of the most important catalysts, zeolite ZSM-5 crystals. These particles look like pieces of Swiss cheese with miniscule channels through which the material that has to be converted must pass. But it seems some of the holes do not want to cooperate leading to differences within one individual catalyst particle.

‘Big Brother’ of catalysis

Like a real ‘Big Brother’, Marianne Kox spied on the zeolites with a combination of different micro-spectroscopic techniques. By doing so, she managed to study the zeolite particles in a space- and time-resolved manner, for example the interior of the catalyst in 3D. She discovered why some of the zeolite crystals were not behaving properly, and how their behaviour differed from one position in the crystal to another.

Depending on the shape of the crystals — for example a boat shape or even the shape of a coffin — the channels inside a zeolite crystal didn’t seem to run properly, and they could get blocked. This was caused by the building blocks that make up the zeolite crystals not fitting together properly. As a result of this the catalyst did not function as well as it could. Thanks to the unique combination of techniques applied by Marianne Kox, individual catalyst particles and their working principles can be studied in more detail, making improvement of the catalyst possible.

Marianne Kox’s research is part of the Vici project run by Bert Weckhuysen. The December 2009 issue of Nature Materials contained the article Morphology-dependent zeolite intergrowth structures leading to distinct internal and outer-surface molecular diffusion barriers, about this research, to which PhD researcher Lukasz Karwacki also contributed.dell inspiron b130 battery,dell inspiron e1405 battery,dell inspiron e1505 battery,dell inspiron e1705 battery,dell latitude d410 battery,dell latitude d420 battery,dell latitude d430 battery.

Simply coating a sheet of paper with ink made of carbon nanotubes and silver nanowires makes a highly conductive storage device, said Yi Cui, assistant professor of materials science and engineering.

“Society really needs a low-cost, high-performance energy storage device, such as batteries and simple supercapacitors,” he said.

Like batteries, capacitors hold an electric charge, but for a shorter period of time. However, capacitors can store and discharge electricity much more rapidly than a battery.

Cui’s work is reported in the paper “Highly Conductive Paper for Energy Storage Devices,” published online in the Proceedings of the National Academy of Sciences.

“These nanomaterials are special,” Cui said. “They’re a one-dimensional structure with very small diameters.” The small diameter helps the nanomaterial ink stick strongly to the fibrous paper, making the dell laptop battery and supercapacitor very durable. The paper supercapacitor may last through 40,000 charge-discharge cycles — at least an order of magnitude more than lithium batteries. The nanomaterials also make ideal conductors because they move electricity along much more efficiently than ordinary conductors, Cui said.

Bing Hu, a post-doctoral fellow, prepares a small square of ordinary paper to with an ink that will deposit nanotubes on the surface that can then be charged with energy to create a battery.

Cui had previously created nanomaterial energy storage devices using plastics. His new research shows that a paper dell inspiron 6000 battery is more durable because the ink adheres more strongly to paper (answering the question, “Paper or plastic?”). What’s more, you can crumple or fold the paper battery, or even soak it in acidic or basic solutions, and the performance does not degrade. “We just haven’t tested what happens when you burn it,” he said.

The flexibility of paper allows for many clever applications. “If I want to paint my wall with a conducting energy storage device,” Cui said, “I can use a brush.” In his lab, he demonstrated the dell inspiron 630m battery to a visitor by connecting it to an LED (light-emitting diode), which glowed brightly.

A paper supercapacitor may be especially useful for applications like electric or hybrid cars, which depend on the quick transfer of electricity. The paper supercapacitor’s high surface-to-volume ratio gives it an advantage.

“This technology has potential to be commercialized within a short time,” said Peidong Yang, professor of chemistry at the University of California-Berkeley. “I don’t think it will be limited to just energy storage devices,” he said. “This is potentially a very nice, low-cost, flexible dell inspiron 6400 battery  electrode for any electrical device.”

Cui predicts the biggest impact may be in large-scale storage of electricity on the distribution grid. Excess electricity generated at night, for example, could be saved for peak-use periods during the day. Wind farms and solar energy systems also may require storage.

“The most important part of this paper is how a simple thing in daily life — paper — can be used as a substrate to make functional conductive electrodes by a simple process,” Yang said. “It’s nanotechnology related to daily life, essentially.”

Cui’s research team includes postdoctoral scholars Liangbing Hu and JangWook Choi, dell inspiron 640m battery,and graduate student Yuan Yang.