Subscribe free to our newsletters via your
. 24/7 Space News .




Subscribe free to our newsletters via your




















ENERGY TECH
Single atom alloy platinum-copper catalysts cut costs, boost green tech
by Staff Writers
Somerville MA (SPX) Oct 13, 2015


Atomic-resolution microscopy shows the single platinum atoms on copper nanoparticles that can split hydrogen into atoms enabling the efficient and selective hydrogenation of butadiene. Image courtesy Tufts University. For a larger version of this image please go here.

A new generation of platinum-copper catalysts that require very low concentrations of platinum in the form of individual atoms to cleanly and cheaply perform important chemical reactions is reported by Tufts University researchers in the journal Nature Communications.

Platinum is used as a catalyst in fuel cells, in automobile converters and in the chemical industry because of its remarkable ability to facilitate a wide range of chemical reactions. However, its future potential uses are significantly limited by scarcity and cost, as well as the fact that platinum readily binds with carbon monoxide, which "poisons" the desired reactions, for example in polymer electrolyte membrane (PEM) fuel cells, which are the leading contenders for small-scale and mobile power generation not based on batteries or combustion engines.

The Tufts researchers discovered that dispersing individual, isolated platinum atoms in much less costly copper surfaces can create a highly effective and cost-efficient catalyst for the selective hydrogenation of 1,3 butadiene, a chemical produced by steam cracking of naphtha or by catalytic cracking of gas oil. Butadiene is an impurity in propene streams that must be removed from the stream through hydrogenation in order to facilitate downstream polymer production. The current industrial catalyst for butadiene hydrogenation uses palladium and silver.

Like Sugar in Coffee
Copper, while a relatively cheap metal, is not nearly as catalytically powerful as platinum, noted Professor of Chemistry Charles Sykes, Ph.D., one of the senior authors on the paper. "We wanted to find a way to improve its performance."

The researchers first conducted surface science experiments to study precisely how platinum and copper metals mix. "We were excited to find that the platinum metal dissolved in copper, just like sugar in hot coffee, all the way down to single atoms. We call such materials single atom alloys," said Sykes.

The Tufts chemists used a specialized low temperature scanning tunneling microscope to visualize the single platinum atoms and their interaction with hydrogen. "We found that even at temperatures as low as minus 300 degrees F these platinum atoms were capable of splitting hydrogen molecules into atoms, indicating that the platinum atoms would be very good at activating hydrogen for a chemical reaction," Sykes said.

With that knowledge, Sykes and his fellow chemists turned to long-time Tufts collaborator Maria Flytzani-Stephanopoulos, Ph.D., the Robert and Marcy Haber Endowed Professor in Energy Sustainability at the School of Engineering, to determine which hydrogenation reaction would be most significant for industrial applications. The answer, she said, was butadiene.

The model catalyst performed effectively for that reaction in vacuum conditions in the laboratory, so Flytzani-Stephanopoulos's team took the study to the next level. They synthesized small quantities of realistic catalysts, such as platinum-copper single atom alloy nanoparticles supported on an alumina substrate, and then tested them under industrial pressure and temperatures.

"To our delight, these catalysts worked very well and their performance was steady for many days," said Flytzani-Stephanopoulos. "While we had previously shown that palladium would do related reactions in a closed reactor system, this work with platinum is our first demonstration of operation in a flow reactor at industrially relevant conditions. We believe this approach is also applicable to other precious metals if added as minority components in copper."

Further, the researchers found that the reaction actually became less efficient when they used more platinum, because clusters of platinum atoms have inferior selectivity compared with individual atoms. "In this case, less is more," said Flytzani-Stephanopoulos, "which is a very good thing."

Environmental Benefits
Because platinum is at the center of many clean energy and green chemicals production technologies, such as fuel cells, catalytic converters, and value-added chemicals from bio-renewable feedstocks, the new, less expensive platinum-copper catalysts could facilitate broader adoption of such environmentally friendly devices and processes, she added.

The work is the latest fruit from a long cross-disciplinary partnership between Sykes and Flytzani-Stephanopoulos.

"Maria and I met more than seven years ago and talked regularly about how to combine our fairly different fields of research into an effective collaboration across the schools of Arts and Sciences and Engineering," said Sykes. "I had a state-of-the-art microscope that could see and manipulate atoms and molecules, and I wanted to use its unique capabilities to gain insight into industrially important chemical reactions.

In the early 2000s, Maria's group had pioneered the single-atom approach for metals anchored on oxide supports as the exclusive active sites for the water-gas shift reaction to upgrade hydrogen streams for fuel cell use.

Catalyst design know-how already existed in her lab. In retrospect, it seems obvious that combining forces would be a 'natural' development. Together we embarked on a new direction involving single atom alloys as catalysts for selective hydrogenation reactions. Our microscope was uniquely suited for characterizing the atomic composition of surfaces. We got funding from the National Science Foundation, U.S. Department of Energy and the Tufts Collaborates initiative to pursue this new area of research."

Sykes and Flytzani-Stephanopoulos have used this approach to design a variety of single atom alloy catalysts that have, in the last two years, sparked international interest.

"Traditionally catalyst development happens by trial and error and screening many materials," said Flytzani-Stephanopoulos. "In this study we took a fundamental approach to understanding the atomic scale structure and properties of single atom alloy surfaces and then applied this knowledge to develop a working catalyst. Armed with this knowledge, we are now ready to compare the stability of these single atom alloy catalysts to single atom catalysts supported on various oxide or carbon surfaces. This may give us very useful criteria for industrial catalyst design."

The research was primarily performed by co-authors Felicia R. Lucci and Jilei Liu, senior graduate students in the Sykes and Stephanopoulos labs, respectively. Other authors on the paper are doctoral students Matthew D. Marcinkowski (chemistry) and Ming Yang (chemical engineering), and Lawrence F. Allard, Ph.D., of the Materials Science and Technology Division, Oak Ridge National Laboratory, who led the state of the art imaging of the catalytic samples. "Selective hydrogenation of butadiene on platinum copper alloys at the single atom limit," Nature Communications, DOI: 10.1038/NCOMMS9550.

Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.

SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only

.


Related Links
Tufts University
Powering The World in the 21st Century at Energy-Daily.com






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

Previous Report
ENERGY TECH
Superconductivity trained to promote magnetization
Moscow, Russia (SPX) Oct 07, 2015
Superconductivity, which is almost incompatible with magneticfield, under certain conditions is able to promote magnetization. Russian scientist Natalya Pugach from the Skobeltsyn Institute of Nuclear Physics at the Lomonosov Moscow State University discovered this yet to be explained effect with her British colleagues, whose theory group headed by Professor Matthias Eschrig. They suggest that t ... read more


ENERGY TECH
Lunar Pox

Space startup confirms plans for robotic moon landings

Asteroids found to be the moon's main 'water supply'

Russian scientist hope to get rocket fuel, water, oxygen from Lunar ice

ENERGY TECH
Pebbles on Mars likely traveled tens of miles down a riverbed

To save on weight, a detour to the moon is the best route to Mars

Opportunity working at 'Marathon Valley' before winter relocation

The Journey to Mars: Bridging the Technology Gap

ENERGY TECH
NASA, Israel ink space cooperation agreement

Magnetic sail tech alternative to rocket-based space travel

NASA Appoints Mark Kirasich To Serve As Orion Program Manager

Back to the Future: Truth is stranger than sci-fi

ENERGY TECH
Latest Mars film bespeaks potential of China-U.S. space cooperation

Exhibition on "father of Chinese rocketry" opens in U.S.

The First Meeting of the U.S.-China Space Dialogue

China's new carrier rocket succeeds in 1st trip

ENERGY TECH
Clearing the Space Fog on ISS

International Space Agencies Meet to Advance Space Exploration

Meet the International Docking Adapter

NASA extends Boeing contract for International Space Station

ENERGY TECH
Both passengers for next Ariane 5 mission arrive in French Guiana

Arianespace signs ARSAT to launch a new satellite for Argentina

Ariane 5 orbits Sky Muster and ARSAT-2

A satellite launcher for the Middle East

ENERGY TECH
Airbus DS ready to start testing exoplanet tracker CHEOPS

Hubble Telescope Spots Mysterious Space Objects

Exoplanet Anniversary: From Zero to Thousands in 20 Years

Mysterious ripples found racing through planet-forming disc

ENERGY TECH
Methodology could lead to more sustainable manufacturing systems

New deposition technique enhances optoelectronic properties of lasers

Mathematicians find 'magic key' to drive Ramanujan's taxi-cab number

Using optical fiber to generate a two-micron laser




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News






The content herein, unless otherwise known to be public domain, are Copyright 1995-2017 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement