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We hope you will find your time with us exciting, challenging and rewarding.

This may not be how you expected to begin your journey with us at KAUST but you will always remember it.

Some key pieces of information regarding your academic program can be found on these web pages, so please look through our PSE Division website for the information available.

If you have any queries about KAUST and your future studies, please contact your Graduate Program Student Advisor who will be happy to assist you.

The video recording of the Physical Science and Engineering Orientation Presentation by Dean Ravi Samtaney is available below and we will upload the individual Academic Program Orientation recordings as they become available.

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​A unique nanocluster of copper atoms created by KAUST researchers could serve as a roadmap to guide the design of new catalysts and imaging agents.

A nanocluster is a type of nanoparticle in which researchers have pinpointed the precise arrangement of every atom, along with their bond lengths and bond angles. This detailed information enables researchers to predict the properties of related clusters, based on their composition and structures. “It provides a practical model for understanding the intrinsic correlations between structure and physical-chemical properties through a combination of experiments and theoretical calculations,” says Ren-Wu Huang of the KAUST Catalysis Center, part of the team behind the new discovery.

Nanoclusters are typically 1–3 nanometers wide and organized into a core and a shell. The atomic structure of the core can determine the nanocluster’s structure, size and optical properties, while the shell affects its stability, solubility and catalytic activity.

Nanoclusters containing copper, silver and gold have potential uses as catalysts, or as nontoxic luminescent imaging agents in living cells. Although silver and gold nanoclusters are well studied, copper nanoclusters have been rather neglected, partly because the metal tends to react with oxygen in air.

The side (left) and top (right) views of the nanocluster reveal that it is a flat core of 17 copper atoms (green). The cluster has 64 more copper atoms in its shell (brown), along with molecules containing sulfur (yellow), nitrogen (blue) and carbon (grey). Hydrogen atoms are omitted for clarity.

Reproduced with permission from reference one © 2020 Journal of the American Chemical Society.

The KAUST team has now created the largest copper-based nanocluster to date, and they are studying it with a range of techniques, including X-ray crystallography and electrospray ionization mass spectrometry. Each 2.8-nanometer-wide cluster contains 81 copper atoms, 46 benzenethiol molecules, 10 tert-butylamine molecules and 32 hydride ions.

Nanoclusters generally have polyhedral cores surrounded by symmetrical shells. But the new copper nanocluster has a flat core of 17 copper atoms, arranged into a repeating pattern of triangles. “This kind of planar core has never been observed in previously reported metal nanoclusters,” says Osman M. Bakr, who led the team.

The nanocluster also has a highly unusual hemispherical shell that is 1.5-nanometers high and covered by benzenethiol molecules. Differences between the curved and flat surfaces of the hemisphere suggest that the flat face has a higher reactivity. In addition, computational calculations provided evidence that the arrangement of these molecules could help to ease the transfer of electrical charge between different clusters within a crystal, which could prove crucial in future applications.

“The development of copper nanoclusters is still in its infancy,” says Huang. “Therefore, the next stage of our research will be the synthesis of copper nanoclusters with a bigger size and novel structure, and exploring their potential applications in the field of catalysis.” 

-KAUST Discovery

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​Innovative materials called metal organic frameworks (MOFs) could become much more versatile following research that shows that they can be manipulated as liquids.

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​The shift to a future marked by carbon-free renewable energy sources is being explored by KAUST researcher Min Suk Cha as societies seek to end our reliance on fire. Cha and his team, including postdoc Ramses Snoeckx are researching electrically generated plasmas as the future of chemical synthesis and manufacturing to replace combustion-driven processes.

"The importance of fire—its acquisition, control or theft—is a recurring theme in the mythologies of cultures across the globe," says Cha, from the Clean Combustion research center. Fire provided our ancestors with the means to cook, heat, hunt, create and protect. Over time, our reliance on fire has only grown. "Since the industrial revolution, combustion has become the foundation of power generation, transportation, smelting and material processing," says Cha. "This was followed rapidly with advances in petrochemistry, producing fertilizers; materials, such as plastics; medicine; and much more."

The downside of fire has become all too clear as the climate-altering side effects of the CO₂ emissions it generates. "But renewable electricity offers a pathway forward," Cha says. Wherever fire has led, electricity has followed, he notes. "Even though we cannot abandon fossil fuels entirely just yet because of energy demands, a controlled transition from the era of fire to an electrified future appears imperative," Cha says.

Electric potential

As energy production shifts from fossil fuel combustion to renewable alternatives, the chemical industry could also transition from combustion-driven to renewables-driven processes. Rather than simply using renewable electricity as an alternative heat source, Cha is investigating a potentially more efficient alternative: directly applying a voltage to the chemical starting materials to trigger new chemical production by generating a plasma. "Plasma technology provides us with the opportunity to utilize the full potential of electrical energy," Cha says.

Plasma-driven reactions often emit light as components in the mixture shed energy following electron impacts© 2020 Ramses Snoeckx

Plasma is often described as the fourth state of matter, in line with solid, liquid and gas. A plasma is a gas in which some or all of the consistent molecules have had electrons ripped free, forming a complex cocktail of electrons, ions, atoms and molecules. Plasmas are common in the natural world, from the center of stars to lightning strikes. They can also be generated and maintained artificially by applying a strong electric field for example. The field accelerates the free electrons, which then canon into other molecules in the mixture, knocking free further electrons to sustain the plasma.

A direct strike by a speeding electron on a molecule can knock another electron free—or it can crack the molecule apart. A water molecule, for example, can split into a hydrogen radical and a hydroxyl radical. "We want to use this type of dissociation as a source of chemical reaction," Cha explains. Although water molecules or CO₂ molecules could be split by heating, it would require a huge amount of energy to heat up the whole gas sample. Using an electric field to accelerate electrons is a far more energy-efficient approach. "We can selectively transfer the electrical energy into the motion of charged particles."

One application of plasma chemistry the team is exploring is to crack apart CO₂ molecules, as the first step in turning captured CO₂ emissions into valuable chemicals.¹ By feeding a mixture of methane and CO₂ into a plasma reactor, researchers can trigger a reaction called dry reforming, which turns the two starting gases into hydrogen and carbon monoxide. This mixture, known as syngas, is a major chemical feedstock used in synthetic liquid fuel production, for example.

Plasma-driven molecular dissociation can also be used for hydrocarbon reforming, taking basic chains of carbon and hydrogen atoms and turning them into something more valuable.² "For example, I could turn CO₂, water and an alkane (a basic hydrocarbon) into an alcohol, an alternative fuel," Cha says.

Control reaction

"The great challenge with plasma-driven chemistry," says Cha, "is maximizing the yield of the desired product from the cocktail of reactive species generated under plasma conditions. My research is focused on how to control the plasma chemistry to make certain target chemicals," he says.

Bubbling reactant gases through an oil or liquid hydrocarbon, such as octane, under plasma reforming conditions can convert the basic hydrocarbon into value-added products.© 2020 Xuming Zhang and Min Suk Cha.

One advantage of plasma-driven over conventional chemistry is that researchers have two independently adjustable ways to supply the reaction with energy. They can separately alter the starting temperature of the reactant gases and the electrical energy applied to accelerate the free electrons in the mixture. "We have shown that electron impact reactions can initiate a chemical reaction regardless of initial conditions, and it is the thermochemistry, governed by the gas temperature, that has a dominant effect on product selectivity," Cha says. "Combining plasma with a catalyst can also improve reaction selectivity," he adds.

"Once control over product formation and selectivity for plasma processes is fully understood, this could pave the way for using plasmas for the on-demand production of tailored chemicals and fuels using renewable electricity," Cha says. Plasmas are already used industrially to manufacture computer chips, he adds. "The transition toward an electrified future is already kindling and we must prepare ourselves for the challenges and opportunities that electrification presents."

Humanity's transition from combustion to electricity may seem a very modern story, but our recognition of electricity's superiority over fire has a long history. "The Greek God Zeus, who punished Prometheus for giving fire to humankind, symbolized his might through lightning—which, of course, is electricity," Cha says. Not just electricity, but an electrically generated plasma.

-KAUST Discovery