Development of copper-nickel catalysts pioneers environmentally friendly and more efficient oxygen and hydrogen production from water electrolysis 

 

 

Research at Khalifa University has led to the development of catalysts designed to improve the electrocatalytic performance of oxygen evolution reactions (OER) in water splitting. This advancement could potentially reduce the reliance on rare and expensive materials currently used in clean oxygen and hydrogen production technologies.

 

Suleiman Musa, Dr. Bilal Masood Pirzada, Shamraiz Hussain Talib, Dr. Dalaver Anjum, Dr. Mohammad Abu Haija, Dr. Sharmarke Mohamed and Dr. Ahsan Ul Haq Qurashi created copper-nickel dual atom catalysts supported on graphene. Their catalysts have demonstrated promising electrochemical properties crucial for efficiently splitting water molecules into oxygen and hydrogen during OER. The graphene base stabilizes the metallic atoms and enhances their activity by facilitating better electron mobility.

 

The team published their results in Nano Energy, a top 1% journal, with the work conducted at the Khalifa University Advanced Materials Chemistry Center.

 

Using advanced characterization techniques like X-ray diffraction and scanning electron microscopy, the team confirmed the successful dispersion of copper and nickel atoms across the graphene surface. Electrochemical tests revealed that the catalysts supported on reduced graphene oxide exhibited the lowest overpotential ­­— a measure of energy efficiency in catalysis — and the highest current density at lower voltages compared to other samples. This indicates a superior catalytic performance and the synergistic effect of the copper-nickel combination, which lowers the energy barrier for oxygen production.

 

By lowering the cost and increasing the efficiency of oxygen production, these copper-nickel graphene catalysts could revolutionize industries that rely on high-purity oxygen, such as healthcare, aerospace, and environmental engineering. Further insights provided by density functional theory calculations helped in understanding the interaction between the copper and nickel atoms and the graphene support at an atomic level. These computational models validated the experimental results and offered a theoretical explanation for the observed increase in catalytic efficiency: The unique electronic interaction between the dual atoms facilitates a more efficient catalytic process compared to single atom setups.

 

As the world continues to seek ways to reduce reliance on fossil fuels and decrease carbon emissions, the implications for sustainable energy technologies are particularly profound, given the potential for these catalysts to facilitate more environmentally friendly approaches to oxygen and hydrogen production.

 

Jade Sterling
Science Writer
24 June 2024

Analysis of zircon crystals unveils the start of Earth’s hydrological cycle

 

Four billion years ago, Earth was a vastly different place. There were no continents as we know them today, no breathable atmosphere, and life, if it existed at all, was in its most primitive forms. However, one of the fundamental processes that has shaped the evolution of life and the surface of our planet might have already been in operation.

 

Khalifa University’s Dr. Hamed Gamaleldien investigated the ancient history of the hydrological cycle to discover when and how the Earth’s water cycle began, helping to reshape our understanding of the planet’s early environment and its capacity to harbor life.

 

With researchers from Curtin University, Australia, Chinese Academy of Sciences, and China University of Petroleum, Dr. Gamaleldien focused on the oxygen isotopic signatures of zircon crystals, robust minerals that can endure geological processes without altering their primary characteristics. Found in the Jack Hills of Western Australia, these crystals can be considered geological time capsules, preserving records of environmental conditions dating back to the early stages of Earth’s formation. By examining the oxygen isotopic composition, the research team have pinpointed the onset of significant interactions between fresh water and the newly emerged continental crust.

 

The team published their results in Nature Geoscience, a top 1% journal.

 

Their results reveal two significant periods of magmatism around four billion years ago and 3.5 billion years ago, marked by very light oxygen isotopic compositions that typically came from hot, freshwater interaction with dry land. This timing is crucial, as it suggests that the hydrological cycle — crucial for creating the conditions necessary for life — began less than 600 million years after the planet’s formation.

 

“We know that minerals in rocks are chemically altered by interactions with water and this was likely happening as far back as 4.4 billion years ago,” Dr. Gamaleldien says. “We weren’t sure whether this water was saline oceanic water, meteoric (fresh), or some combination thereof, but our results show that it would be impossible for the zircon crystals to contain such light oxygen isotope signatures if the water was only salt water. There had to have been some fresh water to get these oxygen levels.”

 

The research team simulated the interactions between fresh water and the zircon crystals and demonstrated that fresh water was required to yield the very isotopically light compositions found in the Jack Hills. This provides compelling evidence for the existence of shallow magmatic-hydrothermal systems involving meteoric water at least as far back as four billion years ago.

 

“These results constrain the time period possible for the earliest presence of dry land and freshwater reservoirs, and the start of the hydrological cycle on Earth,” Dr. Gamaleldien says. “which represent the main gradients for the evolution of life.”

 

As the continents formed and stabilized, they provided platforms for the accumulation of sediments and organic materials, necessary components for the development of life.

 

The team’s results push back the timeline for the onset of the hydrological cycle and underscore the interconnectedness of geological processes and biological evolution. The presence of fresh water interacting with solid rock not only shaped the physical landscape but also created conditions perfect for the evolution of life from simple single-celled organisms to complex ecosystems. The results also challenge previous notions about the barrenness of early Earth and provide insights into the resilience and adaptability of planetary environments.

 

Understanding the timing and evolution of Earth’s hydrological cycle helps reconstruct the planet’s climatic history and can even offer clues about how life might arise on other planets, providing a broader context for the search for extraterrestrial life. 

 

Jade Sterling
Science Writer
24 June 2024

Research develops a novel control approach to mitigate delays in communication to enhance microgrid resilience

 

Microgrids, localized groups of electricity sources and loads, have become pivotal in decentralized energy systems. Their dependency on communication for distributed control introduces vulnerabilities, particularly in the form of communication delays that can destabilize the system. Prof. Ahmed Al-Durra, Dr. Khaled Ali Al-Jaafari, Prof. Hatem Zeineldin and Prof. Ehab El-Saadany, with researchers from University of Alberta, Canada, explored innovative modifications to microgrid control structures that can enhance their robustness against such delays, ensuring improved system stability without compromising control responsiveness.

 

The team published their results in Applied Energy, a top 1% journal.

 

Microgrids use distributed secondary control strategies to manage energy resources like solar panels, wind turbines and batteries efficiently. This control is crucial for maintaining system stability, frequency, and voltage within desired limits but the inherent delays in communication networks can pose significant challenges.

 

The research team proposed an enhanced control strategy that incorporates additional feedback loops into the distributed generator’s control mechanism. These modifications aim to improve the system’s ability to handle communication delays by enhancing the dynamic response of the control system. This approach differs from traditional methods that often require significant bandwidth and computational resources, focusing instead on local adjustments that reduce the system’s overall sensitivity to delays.

 

In developing their strategy, the team used a combination of mathematical modelling and simulation tests to evaluate effectiveness. By incorporating supplementary local feedback signals within each distributed generator, the modified control structure was able to maintain stability and respond to disturbances more effectively than conventional systems.

 

Simulation results demonstrated a significantly improved resilience to communication delays, with the additional feedback loops allowing a wider range of permissible control parameters and greater flexibility in system tuning. This is particularly key in environments where communication delays are unpredictable and vary widely, such as in remote or heavily networked microgrids.

 

As microgrids become more common and renewable energy sources are further incorporated, robust control mechanisms are increasingly important for more reliable and resilient power systems. The research team’s proposed control structures not only stabilize the microgrid under varying communication conditions but also ensure that the energy distribution remains efficient and stable, even in challenging operational environments.

 

Jade Sterling 
Science Writer 
14 June 2024