Scientists have found a way to make their asphalt-based sorbents better at capturing carbon dioxide from gas wells: Adding water.

The lab of chemist James Tour, a chair in chemistry as well as a professor of computer science and of materials science and nanoengineering at Rice University, discovered that treating grains of inexpensive Gilsonite asphalt with water allows the material to adsorb more than two times its weight in the greenhouse gas. The treated asphalt selects carbon dioxide over valuable methane at a ratio of more than 200-to-1.

The material performs well at ambient temperatures and under the pressures typically found at wellheads. When the pressure abates, the material releases the carbon dioxide, which can then be stored, sold for other industrial uses, or pumped back downhole.

Natural gas at the wellhead typically contains between 3 and 7 percent carbon dioxide, but at some locations may contain up to 70 percent. Oil and gas producers traditionally use one of two strategies to sequester carbon dioxide: physically through the use of membranes or solid sorbents like zeolites or porous carbons, or chemically through filtering with liquid amine, a derivative of ammonia.

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Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, report engineers.

Materials scientist Rouzbeh Shahsavari of Rice University and alumnus Navid Sakhavand first built atom-level computer models of pillared graphene—sheets of graphene connected by covalently bonded carbon nanotubes—to discover their strength and electrical properties as well as their thermal conductivity.

In a new study, they found that manipulating the joints between the nanotubes and graphene has a significant impact on the material’s ability to direct heat. That could be important as electronic devices shrink and require more sophisticated heat sinks.

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A reversible fabric keeps skin a comfortable temperature whatever the weather—and could save energy by keeping us away from the thermostat.

As reported in Science Advances, the double-sided fabric is based on the same material as everyday kitchen wrap and can offer warmth or cooling depending on which side faces out.

“Why do you need to cool and heat the whole building? Why don’t you cool and heat individual people?” says Yi Cui, professor of materials science and engineering at Stanford University, who thought if people could be more comfortable in a range of temperatures, they could save energy on air conditioning and central heating.

Thirteen percent of all of the energy consumed in the United States is due to indoor temperature control. But for every 1 degree Celsius (1.8 degrees Fahrenheit) that a thermostat is turned down, a building can save a whopping 10 percent of its heating energy—and the reverse is true for cooling. So adjusting temperature controls by just a few degrees could have major effects on energy consumption.

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Researchers have developed a type of “smart paper” that can conduct electricity and detect water.

The paper, laced with conductive nanomaterials, can be employed as a switch, turning on or off an LED light, or as an alarm system indicating the absence or presence of water.

In cities and large-scale manufacturing plants, a water leak in a complicated network of pipes can take tremendous time and effort to detect, as technicians must disassemble many pieces to locate the problem.

The American Water Works Association indicates that nearly a quarter-million water line breaks occur each year in the United States, costing public water utilities about $2.8 billion annually.

The smart paper could simplify the process for discovering detrimental leaks.

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Scientists have learned how to tame the unruly electrons in graphene.

Graphene is a nano-thin layer of the carbon-based graphite in pencils. It is far stronger than steel and a great conductor. But when electrons move through it, they do so in straight lines and their high velocity does not change. “If they hit a barrier, they can’t turn back, so they have to go through it,” says Eva Y. Andrei, professor in the Rutgers University-New Brunswick department of physics and astronomy and the study’s senior author.

“People have been looking at how to control or tame these electrons.”

Graphene is a better conductor than copper and is very promising for electronic devices.

The new research “shows we can electrically control the electrons in graphene,” says Andrei. “In the past, we couldn’t do it. This is the reason people thought that one could not make devices like transistors that require switching with graphene, because their electrons run wild.”

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Using unique design and building methods, researchers have created a prototype for an ultra-thin, curving concrete roof that will also generate solar power.

The self-supporting, doubly curved shell roof has multiple layers: the heating and cooling coils and the insulation are installed over the inner concrete layer. A second, exterior layer of the concrete sandwich structure encloses the roof, onto which builders install thin-film photovoltaic cells.

Philippe Block, a professor of architecture and structures at ETH Zurich, and Arno Schlüter, a professor of architecture and building systems, led the team. They want to put the new lightweight construction to the test and combine it with intelligent and adaptive building systems.

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Lithium batteries made with asphalt could charge 10 to 20 times faster than the commercial lithium-ion batteries currently available.

The researchers developed anodes comprising porous carbon made from asphalt that show exceptional stability after more than 500 charge-discharge cycles.

A high-current density of 20 milliamps per square centimeter demonstrates the material’s promise for use in rapid charge and discharge devices that require high-power density.

“The capacity of these batteries is enormous, but what is equally remarkable is that we can bring them from zero charge to full charge in five minutes, rather than the typical two hours or more needed with other batteries,” says James Tour, the chair in chemistry and a professor of computer science and of materials science and nanoengineering at Rice University.

The Tour lab previously used a derivative of asphalt—specifically, untreated gilsonite, the same type used for the battery—to capture greenhouse gases from natural gas. This time, the researchers mixed asphalt with conductive graphene nanoribbons and coated the composite with lithium metal through electrochemical deposition.

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A new device has given scientists a nanoscale glimpse of crevice and pitting corrosion as it happens.

Corrosion affects almost everything made of metal—cars, boats, underground pipes, and even the fillings in your teeth.

It carries a steep price tag—trillions of dollars annually—not mention, the potential safety, environmental, and health hazards it poses.

“Corrosion has been a major problem for a very long time,” says Jacob Israelachvili, a chemical engineering professor at the University of California, Santa Barbara.

Confined spaces

Particularly in confined spaces—thin gaps between machine parts, the contact area between hardware and metal plate, behind seals and under gaskets, seams where two surfaces meet—close observation of such electrochemical dissolution had been an enormous challenge. But, not any more.

Using a device called the Surface Forces Apparatus (SFA), Israelachvili and colleagues were able to get a real-time look at the process of corrosion on confined surfaces.

“With the SFA, we can accurately determine the thickness of our metal film of interest and follow the development over time as corrosion proceeds,” says project scientist Kai Kristiansen.

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Researchers have developed an inexpensive and scalable technique that can change plastic’s molecular structure to help it cast off heat.

Advanced plastics could usher in lighter, cheaper, more energy-efficient product components, including those used in vehicles, LEDs, and computers—if only they were better at dissipating heat.

The concept can likely be adapted to a variety of other plastics. In preliminary tests, it made a polymer about as thermally conductive as glass—still far less so than metals or ceramics, but six times better at dissipating heat than the same polymer without the treatment.

“Plastics are replacing metals and ceramics in many places, but they’re such poor heat conductors that nobody even considers them for applications that require heat to be dissipated efficiently,” says Jinsang Kim, a materials science and engineering professor at the University of Michigan. “We’re working to change that by applying thermal engineering to plastics in a way that hasn’t been done before.”

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Scientists have turned wood into an electrical conductor by making its surface graphene.

Chemist James Tour of Rice University and his colleagues used a laser to blacken a thin film pattern onto a block of pine. The pattern is laser-induced graphene (LIG), a form of the atom-thin carbon material discovered at Rice in 2014.

“It’s a union of the archaic with the newest nanomaterial into a single composite structure,” Tour says.

Previous iterations of LIG were made by heating the surface of a sheet of polyimide, an inexpensive plastic, with a laser. Rather than a flat sheet of hexagonal carbon atoms, LIG is a foam of graphene sheets with one edge attached to the underlying surface and chemically active edges exposed to the air.

Not just any polyimide would produce LIG, and some woods work better than others, Tour says. The research team tried birch and oak, but found that pine’s cross-linked lignocellulose structure made it better for the production of high-quality graphene than woods with a lower lignin content. Lignin is the complex organic polymer that forms rigid cell walls in wood.

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