graphene tagged posts

Hidden talents: Converting Heat into Electricity with Pencil and Paper

This is a sketch of the experiment. Credit: HZB

This is a sketch of the experiment. Credit: HZB

Thermoelectric materials can use thermal differences to generate electricity. Now there is an inexpensive and environmentally friendly way of producing them with the simplest of components: a normal pencil, photocopy paper, and conductive paint are sufficient to convert a temperature difference into electricity via the thermoelectric effect. Thermoelectric materials need to have low thermal conductivity despite their high electrical conductivity. Thermoelectric devices made of inorganic semiconductor materials such as bismuth telluride are already being used today in certain technological applications. However, such material systems are expensive and their use only pays off in certain situations...

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Ruthenium Rules for New Fuel Cells

Single-Atomic Ruthenium Catalytic Sites on Nitrogen-Doped Graphene for Oxygen Reduction Reaction in Acidic Medium. ACS Nano, 2017; DOI: 10.1021/acsnano.7b02148

Single-Atomic Ruthenium Catalytic Sites on Nitrogen-Doped Graphene for Oxygen Reduction Reaction in Acidic Medium. ACS Nano, 2017; DOI: 10.1021/acsnano.7b02148

Project disperses single atoms on graphene to match platinum standard. Rice University scientists have fabricated a durable catalyst for high-performance fuel cells by attaching single ruthenium atoms to graphene. Catalysts that drive the oxygen reduction reaction that lets fuel cells turn chemical energy into electricity are usually made of platinum, which stands up to the acidic nature of the cell’s charge-carrying electrolyte. But platinum is expensive.

The ruthenium-graphene combination may fit the bill...

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Quantum Nanoscope: Seeing electrons surfing the waves of light on Graphene

Electrons and light are moving in concert along the graphene sheet. Credit: ICFO/ F. Vialla

Electrons and light are moving in concert along the graphene sheet.
Credit: ICFO/ F. Vialla

Researchers have studied how light can be used to “see” the quantum nature of an electronic material. They managed to do that by capturing light in a net of carbon atoms and slowing down light it down so that it moves almost as slow as the electrons in the graphene. Then something special happens: electrons and light start to move in concert, unveiling their quantum nature at such large scale that it could observed with a special type of microscope.

The experiments were performed with ultra-high quality graphene...

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Nano ‘Sandwich’ offers Unique Properties

Nanoclusters of magnesium oxide sandwiched between layers of graphene make a compound with unique electronic and optical properties, according to researchers at Rice University who made computer simulations of the material. Credit: Lei Tao/Rice University

Nanoclusters of magnesium oxide sandwiched between layers of graphene make a compound with unique electronic and optical properties, according to researchers at Rice University who made computer simulations of the material. Credit: Lei Tao/Rice University

Rice University researchers simulate 2D hybrids for optoelectronics. Rice University researchers have modeled a nanoscale sandwich, the first in what they hope will become a molecular deli for materials scientists. They put 2 slices of atom-thick graphene around nanoclusters of magnesium oxide that give the super-strong, conductive material expanded optoelectronic properties.

Rice materials scientist Rouzbeh Shahsavari and his colleagues built computer simulations of the compound and found it would offer features suitable for sensitive mo...

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