From The University of New South Wales (AU) Via Science Blog: “Room-temperature platinum catalysis could be boon for environment”

U NSW bloc

From The University of New South Wales (AU)

Via

Science Blog

June 6, 2022
University of New South Wales

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Researchers in Australia have been able to use trace amounts of liquid platinum to create cheap and highly efficient chemical reactions at low temperatures, opening a pathway to dramatic emissions reductions in crucial industries.

When combined with liquid gallium, the amounts of platinum required are small enough to significantly extend the earth’s reserves of this valuable metal, while potentially offering more sustainable solutions for CO2 reduction, ammonia synthesis in fertiliser production, and green fuel cell creation, together with many other possible applications in chemical industries.

These findings, which focus on platinum, are just a drop in the liquid metal ocean when it comes to the potential of these catalysis systems. By expanding on this method, there could be more than 1,000 possible combinations of elements for over 1,000 different reactions.

The results are published in the journal Nature Chemistry.

Platinum is very effective as a catalyst (the trigger for chemical reactions) but is not widely used at industrial scale because it’s expensive. Most catalysis systems involving platinum also have high ongoing energy costs to operate.

Normally, the melting point for platinum is 1,700°C. And when it’s used in a solid state for industrial purposes, there needs to be around 10% platinum in a carbon-based catalytic system.

It’s not an affordable ratio when trying to manufacture components and products for commercial sale.

That could be set to change in the future, though, after scientists at UNSW Sydney and RMIT University found a way to use tiny amounts of platinum to create powerful reactions, and without expensive energy costs.

The team, including members of the ARC Centre of Excellence in Exciton Science and the ARC Centre of Excellence in Future Low Energy Technologies, combined the platinum with liquid gallium, which has a melting point of just 29.8°C – that’s room temperature on a hot day. When combined with gallium, the platinum becomes soluble. In other words, it melts, and without firing up a hugely powerful industrial furnace.

For this mechanism, processing at an elevated temperature is only required at the initial stage, when platinum is dissolved in gallium to create the catalysis system. And even then, it’s only around 300°C for an hour or two, nowhere near the continuous high temperatures often required in industrial-scale chemical engineering.

Contributing author Dr Jianbo Tang of UNSW likened it to a blacksmith using a hot forge to make equipment that will last for years.

“If you’re working with iron and steel, you have to heat it up to make a tool, but you have the tool and you never have to heat it up again,” he said.

“Other people have tried this approach but they have to run their catalysis systems at very high temperatures all the time.”

To create an effective catalyst, the researchers needed to use a ratio of less than 0.0001 platinum to gallium. And most remarkably of all, the resulting system proved to be over 1,000 times more efficient than its solid-state rival (the one that needed to be around 10% expensive platinum to work)

The advantages don’t stop there – because it’s a liquid-based system, it’s also more reliable. Solid-state catalytic systems eventually clog up and stop working. That’s not a problem here. Like a water feature with a built-in fountain, the liquid mechanism constantly refreshes itself, self-regulating its effectiveness over a long period of time and avoiding the catalytic equivalent of pond scum building up on the surface.

Dr Md. Arifur Rahim, the lead author from UNSW Sydney, said: “From 2011, scientists were able to miniaturize catalyst systems down to the atomic level of the active metals. To keep the single atoms separated from each other, the conventional systems require solid matrices (such as graphene or metal oxide) to stabilize them. I thought, why not using a liquid matrix instead and see what happens.

“The catalytic atoms anchored onto a solid matrix are immobile. We have added mobility to the catalytic atoms at low temperature by using a liquid gallium matrix”.

The mechanism is also versatile enough to perform both oxidation and reduction reactions, in which oxygen is provided to or taken away from a substance respectively.

The UNSW experimentalists had to solve some mysteries to understand these impressive results. Using advanced computational chemistry and modelling, their colleagues at RMIT, led by Professor Salvy Russo, were able to identify that the platinum never becomes solid, right down to the level of individual atoms.

Exciton Science Research Fellow Dr Nastaran Meftahi revealed the significance of her RMIT team’s modelling work.

“What we found is the two platinum atoms never came into contact with each other,” she said.

“They were always separated by gallium atoms. There is no solid platinum forming in this system. It’s always atomically dispersed within the gallium. That’s really cool and it’s what we found with the modelling, which is very difficult to observe directly through experiments.”

Surprisingly, it’s actually the gallium that does the work of driving the desired chemical reaction, acting under the influence of platinum atoms in close proximity.

Exciton Science Associate Investigator Dr Andrew Christofferson of RMIT explained how novel these results are: “The platinum is actually a little bit below the surface and it’s activating the gallium atoms around it. So the magic is happening on the gallium under the influence of platinum.

“But without the platinum there, it doesn’t happen. This is completely different from any other catalysis anyone has shown, that I’m aware of. And this is something that can only have been shown through the modelling.”

See the full article here.

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In late August 2018, a note appeared on the home page which said that ScienceBlogs was now part of the Science 2.0 family and that plans were in place to make the site active once again.

U NSW Campus

The The University of New South Wales is an Australian public university with its largest campus in the Sydney suburb of Kensington.

Established in 1949, UNSW is a research university, ranked 44th in the world in the 2021 QS World University Rankings and 67th in the world in the 2021 Times Higher Education World University Rankings. UNSW is one of the founding members of the Group of Eight, a coalition of Australian research-intensive universities, and of Universitas 21, a global network of research universities. It has international exchange and research partnerships with over 200 universities around the world.

According to the 2021 QS World University Rankings by Subject, UNSW is ranked top 20 in the world for Law, Accounting and Finance, and 1st in Australia for Mathematics, Engineering and Technology. UNSW also leads Australia in Medicine, where the median ATAR (Australian university entrance examination results) of its Medical School students is higher than any other Australian medical school. UNSW enrolls the highest number of Australia’s top 500 high school students academically, and produces more millionaire graduates than any other Australian university.

The university comprises seven faculties, through which it offers bachelor’s, master’s and doctoral degrees. The main campus is in the Sydney suburb of Kensington, 7 kilometres (4.3 mi) from the Sydney CBD. The creative arts faculty, UNSW Art & Design, is located in Paddington, and subcampuses are located in the Sydney CBD as well as several other suburbs, including Randwick and Coogee. Research stations are located throughout the state of New South Wales.

The university’s second largest campus, known as UNSW Canberra at ADFA (formerly known as UNSW at ADFA), is situated in Canberra, in the Australian Capital Territory (ACT). ADFA is the military academy of the Australian Defense Force, and UNSW Canberra is the only national academic institution with a defense focus.

Research centres

The university has a number of purpose-built research facilities, including:

UNSW Lowy Cancer Research Centre is Australia’s first facility bringing together researchers in childhood and adult cancers, as well as one of the country’s largest cancer-research facilities, housing up to 400 researchers.

The Mark Wainwright Analytical Centre is a centre for the faculties of science, medicine, and engineering. It is used to study the structure and composition of biological, chemical, and physical materials.

UNSW Canberra Cyber is a cyber-security research and teaching centre.

The Sino-Australian Research Centre for Coastal Management (SARCCM) has a multidisciplinary focus, and works collaboratively with the Ocean University of China [中國海洋大學](CN) in coastal management research.

University rankings

In the 2022 QS World University Rankings, UNSW is ranked 43rd globally (4th in Australia and 2nd in New South Wales). In addition, UNSW is ranked 13th in the World for Civil and Structural Engineering (1st in Australia), 20th in the World for Accounting and Finance (1st in Australia), 14th in the World for Law (2nd in Australia), and 23rd in the World for Engineering and Technology (1st in Australia), According to the 2022 QS World University Rankings by Subject.

In the 2022 SCImago Institutions Rankings UNSW is ranked 56th in the world overall and 47th in the world for research. Subject-wise, it is ranked 11th in the world for Business, Management and Accounting, 11th in the World for Law and 33rd in the world for Economics, Econometrics and Finance etc.

In The 2022 U.S. News & World Report Best Global University Ranking UNSW is ranked 41st best university in the world and 45th globally in Economics and Business.

The Times Higher Education World University Rankings 2022 placed UNSW 70th in the world, and 46th in the world (1st in Australia) for Engineering, 55th in the world for Business and Economics (4th in Australia), and 24th in the world (2nd in Australia) for Law according to the 2022 Times Higher Education World University Rankings by subject.

In the 2021 Academic Ranking of World Universities, UNSW is ranked 65th globally, 3rd in Australia and 1st in New South Wales. Also in 2021, UNSW had more subjects ranked in the Academic Ranking of World Universities than any other Australian university, with 19 subjects in the top 50 and 2 subjects in the top 10 in the world. UNSW had 12 subjects ranked first in Australia, including Water Resources (8th in the world), Civil Engineering (12th in the world), Library and Information Science (11th in the world), Remote Sensing (12th in the world), and Finance (21st in the world).

In the 2021 University Ranking by Academic Performance Field Rankings, UNSW is ranked 12th in the world for Commerce, Management, Tourism and Services and 21st Globally for Business. In the 2021 Performance Ranking of Scientific Papers for World Universities, UNSW is ranked 51st Globally and is also ranked 39th in the world in the Economics/Business category. According to the 2021 U-Multirank World University Rankings, UNSW is ranked 28th in the world for Research and also ranked 2nd in Australia across Teaching, Research, Knowledge Transfer, International Orientation and Regional Engagement.

In the 2021 Korea University Business School Worldwide Business Research Rankings UNSW is ranked 1st worldwide for Finance, 11th in the world for Accounting and 27th globally for management. According to the 2021 Washington University Olin Business School’s CFAR Rankings, UNSW is ranked 16th in the world for Finance and 9th in the world for Business, by total outcome indicator of research excellence.

Study abroad

The university has overseas exchange programs with over 250 overseas partner institutions. These include Princeton University, McGill University [Université McGill] (CA), University of Pennsylvania (inc. Wharton), Duke University, Johns Hopkins University, Brown University, Columbia University (summer law students only), The University of California-Berkeley, The University of California-Santa Cruz (inc. Baskin), The University of California-Los Angeles, The University of Michigan (inc. Ross), New York University (inc. Stern), The University of Virginia, The Mississippi State University, Cornell University, The University of Connecticut, The University of Texas-Austin (inc. McCombs), Maastricht University [Universiteit Maastricht](NL), The University of Padua [Università degli Studi di Padova](IT), The University College London (law students only), The University of Nottingham (UK), Imperial College London (UK), The London School of Economics (UK) and The Swiss Federal Institute of Technology ETH Zürich [Eidgenössische Technische Hochschule Zürich)](CH).

In 2017, UNSW enrolled the highest number of Australia’s top 500 high school students academically.

UNSW has produced more millionaires than any other Australian university, according to the Spear’s Wealth Management Survey in 2016.

The Australian Good Universities Guide 2014 scored UNSW 5-star ratings across 10 categories, more than any other Australian university. Monash University ranked second with seven five stars, followed by The Australian National University (AU), Melbourne University (AU) and The University of Western Australia (AU) with six each.

Engineers Australia ranked UNSW as having the highest number of graduates in Australia’s Top 100 Influential Engineers 2013″ list at 23%, followed by Monash University at 8%, the University of Western Australia, The University of Sydney (AU) and The University of Queensland (AU) at 7%.