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Scientists Find Efficient Way to Convert Carbon Dioxide into Ethylene | Chemistry, Materials Science – Sci-News.com

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A team of U.S. researchers has developed copper nanowires with rich surface steps to catalyze a chemical reaction that reduces carbon dioxide (CO2) emissions while generating ethylene (C2H4), an important chemical used to produce plastics, solvents, cosmetics and other important products globally.

Copper represents an effective catalyst in reducing carbon dioxide to hydrocarbons or oxygenates, but it is often plagued by a low product selectivity and limited long-term stability. Choi et al report that copper nanowires with rich surface steps exhibit a remarkably high Faradaic efficiency for ethylene that can be maintained for over 200 hours. Image credit: Choi et al, doi: 10.1038/s41929-020-00504-x.

“The idea of using copper to catalyze this reaction has been around for a long time, but the key is to accelerate the rate so it is fast enough for industrial production,” said co-lead author Professor William Goddard III, a researcher in the Department of Applied Physics and Materials Science at Caltech.

“This study shows a solid path towards that mark, with the potential to transform ethylene production into a greener industry using carbon dioxide that would otherwise end up in the atmosphere.”

Using copper to kick start the carbon dioxide reduction into ethylene reaction has suffered two strikes against it.

First, the initial chemical reaction also produced hydrogen and methane — both undesirable in industrial production.

Second, previous attempts that resulted in ethylene production did not last long, with conversion efficiency tailing off as the system continued to run.

To overcome these two hurdles, Professor Goddard III and colleagues focused on the design of the copper nanowires with highly active steps — similar to a set of stairs arranged at atomic scale.

One intriguing finding of this collaborative study is that this step pattern across the nanowires’ surfaces remained stable under the reaction conditions, contrary to general belief that these high energy features would smooth out.

This is the key to both the system’s durability and selectivity in producing ethylene, instead of other end products.

The scientists demonstrated a carbon dioxide-to-ethylene conversion rate of greater than 70%, much more efficient than previous designs, which yielded at least 10% less under the same conditions.

The new system ran for 200 hours, with little change in conversion efficiency, a major advance for copper-based catalysts.

In addition, the comprehensive understanding of the structure-function relation illustrated a new perspective to design highly active and durable carbon dioxide reduction catalyst in action.

“We are at the brink of fossil fuel exhaustion, coupled with global climate change challenges,” said co-lead author Professor Yu Huang, a researcher in the Department of Materials Science and Engineering at the University of California, Los Angeles.

“Developing materials that can efficiently turn greenhouse gases into value-added fuels and chemical feedstocks is a critical step to mitigate global warming while turning away from extracting increasingly limited fossil fuels.”

“This integrated experiment and theoretical analysis presents a sustainable path towards carbon dioxide upcycling and utilization.”

The team’s paper was published in the journal Nature Catalysis.

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C. Choi et al. Highly active and stable stepped Cu surface for enhanced electrochemical CO2 reduction to C2H4. Nat Catal, published online September 7, 2020; doi: 10.1038/s41929-020-00504-x

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NASA astronaut Kate Rubins votes from the ISS: “If we can…

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This story is part of 2020 elections, CNET’s coverage of the November vote preparations.

Whichever way you cast your vote, you must admire this NASA astronaut who managed to cast her vote from space. Kate Rubins, currently on duty aboard the International Space Station, posted a photo of herself in front of a padded booth labeled “ISS Voting Booth” with the text “From the International Space Station: I voted today”.

NASA notes that this is not Rubins’ first vote from space. She did this in 2016 when she was also on the ISS.

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“I think it’s really important that everyone votes,” said Rubins in a video uploaded by NASA. “And if we can get it out of space, then I believe people can do it from the ground too.” Rubins’ six-month ISS mission began on October 14, which was also her 42nd birthday.

Most astronauts choose the Texas resident election because they move to Houston to train. However, NASA said those wishing to vote as residents of their home state can take special precautions.

Ballot papers from the district in which the astronaut is registered are tested on a training computer at the space station. The actual voting slip is then generated and forwarded to the ISS with the log-in information specific to the crew in order to ensure safety. The completed voting slip is electronically returned to Earth for official return.

“Voting in space has been possible since 1997, when a law was passed that allowed legal voting in space in Texas,” NASA said in a statement. “Since then, several NASA astronauts have performed this civic duty from orbit. As NASA works towards sending astronauts to the moon and eventually Mars in 2024, the agency plans to continue to ensure that astronauts who want to vote in space are able no matter where in the solar system they may be. ”

NASA had expected the U.S. astronauts to vote with Rubins from space on the SpaceX Crew 1 mission to the ISS, but their mission has been postponed until early to mid-November so they can now vote from Earth.

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SpaceX reaches 100 successful launches with Starlink mission – SpaceNews

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WASHINGTON — SpaceX launched another set of Starlink satellites Oct. 24, marking the 100th time the company has placed payloads into orbit.

The Falcon 9 rocket lifted off from Space Launch Complex 40 at Cape Canaveral Air Force Station at 11:31 a.m. Eastern. The rocket’s upper stage deployed the payload of 60 Starlink satellites into orbit 63 minutes after liftoff. The first stage, making its third flight, landed on a droneship in the Atlantic Ocean.

This was the 100th successful launch in the company’s history. That total includes 95 Falcon 9, three Falcon Heavy and two Falcon 1 launches. The company also suffered three Falcon 1 launch failures and one Falcon 9 launch failure; another Falcon 9 was destroyed in 2016 during preparations for a static-fire test.

The launch was the third Starlink mission in less than two weeks, after Falcon 9 launches Oct. 6 and Oct. 18 that each carried 60 Starlink satellites into orbit. The company has now launched 895 Starlink satellites, 55 of which have reentered either because of passive orbital decay or by being actively deorbited.

SpaceX has boasted in filings with the Federal Communications Commission of the high reliability of the Starlink satellites. That included an Oct. 15 filing about an ex parte meeting between SpaceX and FCC staff where the company noted “the successful launch and operation of nearly 300 additional satellites without a failure” since an earlier report filed with the FCC.

That streak, though, may have been broken on the previous launch. Satellite observers noted that one of the satellites on the Oct. 18 launch, identified as Starlink-1819, was not raising its orbit like the other 59. Tracking data showed that satellite’s orbit was instead decaying, suggesting it had malfunctioned.

SpaceX and its competitors have debated the reliability of Starlink satellites in a series of FCC filings in recent weeks. Viasat has argued that the failure rate of Starlink satellites is far higher than what SpaceX has promised, although the company made that argument in part on the apparent deliberate deorbiting of the original 60 “v0.9” Starlink satellites launched in May 2019.

The recent surge in Starlink launches is taking place as two other Falcon 9 missions remain on hold. The last-second scrub of a Falcon 9 launch of a GPS 3 satellite Oct. 2 has yet to be rescheduled, and the investigation into the gas generator problem that caused the scrub led NASA to postpone the Falcon 9 launch of the Crew-1 commercial crew mission, which had been scheduled for Oct. 31.

The Crew-1 launch remains on hold. In a series of tweets Oct. 21, Kathy Lueders, NASA associate administrator for human exploration and operations, said investigators were making “good progress” on understanding the engine issue, but that they were not ready to report the cause of the problem.

She did note that SpaceX will replace one Merlin engine on both the booster that will be used for the Crew-1 mission and the booster for the launch of the Sentinel-6 Michael Freilich ocean science satellite, scheduled for Nov. 10 from Vandenberg Air Force Base. The Sentinel-6 Michael Freilich launch remains on schedule for that launch even with the engine swap, she said.

The earliest Crew-1 would launch is mid-November, Lueders said. “We will want a few days between Sentinel-6 and Crew-1 to complete data reviews and check performance. Most importantly, we will fly all our missions when we are ready.”

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SpaceX launches 60 more Starlink internet satellites from Cape Canaveral – CBS News

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A SpaceX Falcon 9 rocket launched 60 more Starlink internet relay satellites on Saturday, boosting the total number launched to date to 895 as the company builds out a planned constellation of thousands designed to provide global high-speed broadband service.

Running two days late because of an on-board camera issue, the Falcon 9’s twice-flown first stage thundered to life at 11:31 a.m. EDT, pushing the 229-foot-tall rocket away from pad 40 at the Cape Canaveral Air Force Station. It was the California rocket builder’s 19th launch so far this year and its 15th Starlink flight.

The climb out of the lower atmosphere went smoothly and, as usual for SpaceX, the Falcon 9’s first stage flew itself back to landing on an off-shore drone ship. After two second stage engine firings, all 60 Starlink satellites were released to fly on their own, chalking up the company’s 95th successful Falcon 9 flight and 100th overall.

SpaceX’s Starlink operation has regulatory approval to launch more than 12,000 of the small satellites in multiple orbital planes, providing commercial users with line-of-sight access to space-based broadband signals from any point on Earth. The company already is testing the service in selected areas.

A SpaceX Falcon 9 rocket climbs away from Cape Canaveral carrying a 15th batch of Starlink internet satellites and boosting the total number launched to date to 895.

William Harwood/CBS News


With Saturday’s launch, SpaceX has put 895 Starlinks into orbit, 180 of them — more satellites than any other company owns — in less than three weeks.

Astrophysicist Jonathan McDowell, a noted spaceflight analyst, reports 53 Starlinks have been deliberately deorbited to date, two re-entered on their own after failures and another 20 no longer appear to be maneuvering. Including the 60 launched Saturday, that leaves some 820 presumably operational Starlinks in orbit.

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