Tracking atoms during fuel cell cycles: KAIST team reveals the atomic-scale secret behind fuel cell catalyst durability

The Korea Advanced Institute of Science and Technology (KAIST)

Facebook

XLinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

<Professor Yongsoo Yang, Professor Eun-Ae Cho, Dr. Chaehwa Jeong, Dr. Joohyuk Lee, Dr. Hyesung Cho, Researcher Kwangho Lee from KAIST>

view more 

Credit: KAIST

Hydrogen fuel cell vehicles have long been hailed as the future of clean mobility: cars that emit nothing but water while delivering high efficiency and power density. Yet a stubborn obstacle remains. The heart of the fuel cell, the platinum-based catalyst, is both expensive and prone to degradation. Over time, the catalyst deteriorates during operation, forcing frequent replacements and keeping hydrogen vehicles costly.

Understanding why and how these catalysts degrade at the atomic level is a longstanding challenge in the catalysis research. Without this knowledge, designing truly durable and affordable fuel cells for mass adoption remains out of reach.

Now, a team led by Professor Yongsoo Yang of the Department of Physics at KAIST (Korea Advanced Institute of Science and Technology), in collaboration with Professor Eun-Ae Cho of KAIST’s Department of Materials Science and Engineering, researchers at Stanford University and the Lawrence Berkeley National Laboratory, has successfully tracked the three-dimensional change of individual atoms inside fuel cell catalysts during thousands of operating cycles. The results provide unprecedented insight into the atomic-scale degradation mechanisms of platinum-nickel (PtNi) catalysts, and demonstrate how gallium (Ga) doping dramatically improves both their performance and durability.

 

A New Atomic “CT Scan” for Catalysts

To achieve this breakthrough, the team utilized a neural network-assisted atomic electron tomography (AET) technique. Much like a CT scan in a hospital reconstructs the inside of the human body from X-ray images, AET determines the positions of thousands of atoms inside nanomaterials from high-resolution electron microscopy images taken at many different angles. By combining these reconstructions with advanced AI-based data correction, the researchers were able to map the exact 3D coordinates and chemical identity of every atom in the nanoparticle catalysts.

This allowed them to directly observe—at single-atom resolution—how the catalysts changed in structure, chemical composition, and internal strain as they were cycled thousands of times under fuel cell operating conditions.

 

Key Findings: Why Gallium Makes a Difference

The researchers compared conventional PtNi catalysts with Ga-doped PtNi catalysts. The results revealed:

a) Shape stability: While undoped PtNi particles gradually lost their advantageous octahedral shape and became more spherical (i.e., the fraction of highly active {111} facets has been reduced), Ga-doped particles retained their octahedral shape even after 12,000 cycles.

b) Chemical stability: In PtNi catalysts, nickel atoms leached from both the surface and subsurface regions, driving structural instability. In Ga-doped catalysts, surface nickel was largely preserved, preventing collapse of the structure.

c) Strain preservation: The compressive strain in PtNi particles, crucial for optimizing oxygen reduction activity, relaxed substantially over time. In contrast, Ga-doped particles maintained near-optimal strain.

 

d) Catalytic performance: By integrating these factors, the researchers showed that while undoped PtNi catalysts lost ~17% of their oxygen reduction activity after 12,000 cycles, Ga-doped PtNi catalysts lost only ~4% and maintained superior activity throughout.

Dr. Yang, who led the research, explained the significance of the results: “These results represent the first time the true 3D atomic-scale degradation dynamics of fuel cell catalysts have been directly visualized. Our findings not only reveal why gallium doping works, but also establish a powerful framework for rationally designing durable, high-efficiency catalysts.”

 

Implications for a Hydrogen-Powered Future

The study demonstrates that neural network-assisted AET can reveal how nanomaterials evolve during real operating conditions, overcoming the limitations of traditional 2D imaging and ensemble-averaged methods. Beyond PtNi catalysts, the technique can be applied to a wide range of nanomaterials and catalytic systems, helping to design the next generation of energy materials with atomic precision.

For the hydrogen economy, this means that more durable catalysts could extend the lifetime of fuel cells, lower replacement costs, and accelerate the widespread adoption of hydrogen-powered vehicles and clean energy technologies.

 

[Figure 1] Three-dimensional atomic structures and catalytic activity of Ga-doped PtNi nanoparticles during potential cycling. The top row shows the 3D atomic structures at different stages (Pristine to 12,000 cycles; blue: platinum, pink: nickel). The bottom row visualizes oxygen reduction reaction (ORR) catalytic activity, where red indicates higher activity. Gallium doping stabilizes the octahedral geometry and preserves highly active {111} facets, enabling sustained catalytic performance even after extensive cycling.

  

Three-dimensional atomic structures and catalytic activity of Ga-doped PtNi nanoparticles during potential cycling. The top row shows the 3D atomic structures at different stages (Pristine to 12,000 cycles; blue: platinum, pink: nickel). The bottom row visualizes oxygen reduction reaction (ORR) catalytic activity, where red indicates higher activity. Gallium doping stabilizes the octahedral geometry and preserves highly active {111} facets, enabling sustained catalytic performance even after extensive cycling

Credit

KAIST

 

This research, with Chaehwa Jeong, Juhyeok Lee, Hyesung Jo, KwangHo Lee from the KAIST as co-first authors, was published online in Nature Communications on August 28th (Title: Atomic-scale 3D structural dynamics and functional degradation of Pt alloy nanocatalysts during the oxygen reduction reaction).

The study was mainly supported by the National Research Foundation of Korea (NRF) Grants funded by the Korean Government (MSIT).

---

Journal

Nature Communications

DOI

10.1038/s41467-025-63448-5 

Method of Research

Meta-analysis

Subject of Research

Not applicable

Article Title

Atomic-scale 3D structural dynamics and functional degradation of Pt alloy nanocatalysts during the oxygen reduction reaction

 

From crosses to crescents: Islamic-Christian art that brought the medieval Mediterranean together

University of Sharjah

Facebook

WeChatBlueskyMessageWhatsAppEmail

 

image: 

Yakutiye Madrasa, Erzurum. Central muqarnas, Islamic ornamental three-dimensional architectural decoration, embellishing a church ceiling, 1310.

view more 

Credit: Richard Piran McClary

Ceramic vessels originating in the Islamic world once adorned the facades of churches and other Christian monuments, while Christian symbols such as the cross embellished columns, slabs, and other architectural elements in numerous mosques and Islamic monuments.

This was the reality of the Medieval Mediterranean, a vast and vibrant region now explored in a new volume that presents compelling evidence of a historic rendezvous where Islam and Christianity engaged, intermingled, and coexisted through art.

The coexistence across this massive and influential region, spanning the coastal littorals of Europe, Asia, and Africa, was not the result of political or diplomatic rapprochement. Rather, it emerged from the power of art objects, both Muslim and Christian, which fostered cross-cultural dialogue and peaceful exchange.

In Muslim and Arabic jargon, the Mediterranean is referred to as al-Baḥr al-Abyadh al-Mutawassiṭ or the White Middle Sea. Historically, Arabs referred to the sea as Bahr al-rum or Sea of the Romans.

“We wanted to depict the Mediterranean not simply as a land of clash, but as a crossroads where Christianity and Islam met, borrowed ideas, and reshaped each other,” said Dr. Sami L. De Giosa, the volume’s lead editor and an Islamic art and architectural historian at the University of Sharjah in the United Arab Emirates.

“It is clear from the evidence that this region was alive with goods of all sorts being carried across seas—textiles, metalwork, ceramics. These objects weren’t merely practical; they were signifiers of power, taste, and belonging, and they told stories of dialogue across faiths.”

The 300-page volume, comprising ten chapters, focuses exclusively on Muslim and Christian artifacts that crossed cultural boundaries even when religious doctrines did not. In their introduction, the editors coin the term “aesthetic space” to describe the multicultural role that art objects played in the medieval Mediterranean.

“In a time when the use of the terms Islamic and Christian for art outside the mosque and the church is becoming increasingly difficult, such a space can also be useful in renegotiating how religious and secular are associated,” the editors write.

The volume’s geographical scope includes nearly two dozen countries with Mediterranean coastlines. Its contributors concentrate on finely crafted metalwork, marble, stone, and dazzling textiles – objects admired regardless of their Christian or Muslim origins.

“The medieval Mediterranean wasn’t a neatly divided world of faith. It was a messy, fascinating, interconnected world where communities often recognized more in each other than we might expect,” explained Dr. De Giosa.

“We learned this by paying attention to what people built, touched, wore, and prayed with. These findings remind us that much of our perception about religious difference is, in fact, contemporary and not rooted in history, as traditionalist views often profess.”

One striking example is the presence of a prominent Christian insignia – the cross – on the columns of the mosque of Sultan al-Nasir Muhammad in Cairo’s Citadel. Although the columns are historically seen as part of medieval spolia, the volume reconstructs the historical narratives behind these architectural objects to illustrate its central thesis of “aesthetic space.”

Many such architectural objects in the Medieval Mediterranean, one of the volume’s chapters shows, represented a “remarkable transportation” from a Christian to a Muslim cultural and architectural context. The chapter delves into the historical occurrence of Islamic slabs in some of Islam’s most fascinating mosques, presenting them as yet another classic example of Medieval spolia.

For instance, the chapter refers to the Byzantine slabs that were inserted in an imperial mosque in Istanbul. The slabs were originally part of the Hagia Sophia, then moved to the Mausoleum of Ottoman Sultan Sulaiman the Magnificent before their transportation to the mosque. 

The volume uncovers both known and lesser-known cases of Christian and Muslim spolia in religious architecture. Though such incorporations may be viewed as sacrilegious by some – Muslims, for instance, traditionally reject the cross – the Christian artifact within a mosque is nonetheless revered within the aesthetic space.

Coptic textiles embroidered with Christian inscriptions, known as tiraz, are presented as examples of the “spoliation of ideas” in the material culture of the medieval Mediterranean. Christians who reprised the style of Islamic tiraz textiles, a luxury medieval Islamic cloth, occasionally transformed them into Christian objects sometimes with Coptic inscriptions.

Most of the volume’s case studies aim to reconstruct the original contexts of such practices through rigorous textual analysis, comparison with material remnants, and impartial interpretation of visual evidence where documentation is lacking.

The volume models the aesthetic space between Christianity and Islam primarily through the transfer of objects across cultural and religious boundaries. This exchange was not one-directional: Muslims incorporated Christian artifacts into their worship and daily lives, just as Christians consumed Islamic goods despite their evident Islamic legacy.

The volume also examines the presence of Islamic ceramic bowls and dishes known as bacini, which were embedded in the facades of Christian monuments in Italy, France, and Germany. Despite their Islamic inscriptions and symbols, these objects were admired and preserved. “The range, variety, and vast geographical extent of the vessels’ point of origin creates its own bacini Mediterranean microhistory,” the volume notes.

Rather than a chasm between faiths, the volume attests to a rich intermingling of Islam and Christianity in the Medieval Mediterranean. Its contributors uncover one piece of evidence after another showing how objects facilitated this cultural dialogue.

The book also explores “hybrid objects” – minute cultural and artistic works that passed through “three hands.” One chapter presents the fascinating story of an Orthodox liturgical object composed of Islamic and Latin elements.

Co-editor Nikolaos Vryzidis of the School of Applied Arts and Culture at the University of West Attica emphasizes that the Mediterranean and its hinterlands were zones of intense contact between diverse religions and languages during the Middle Ages. “They offer a rich array of intercultural contexts, which is an ideal setting for the kind of interdisciplinary inquiry we sought to pursue.”

The intermingling of Christianity and Islam is clearly illustrated in a chapter of the volume where the authors examine the presence of Muslim muqarnas, also known as honeycomb vaulting, in churches located in Anatolia and Mosul, in present-day Iraq. Although neither region borders the Mediterranean coast, the volume considers them as part of its cultural hinterlands.

Muqarnas, three-dimensional Islamic architectural ornaments, appear in Christian contexts and are described by the editors as “a contemporary and boundary-crossing decoration of the time, like so many architectural devices of the past, freely borrowed and imbued with specific meanings in different contexts.”

The contributors to this book show how porous the boundaries of faith and culture were in the medieval Mediterranean, particularly in relation to art and objects. Craftsmen, as the volume shows, followed a kind of “first-come, first-served” logic regardless of the religious connotation of objects.

“They (craftsmen) worked for whoever paid, not for one religion alone. A patron might be Christian, Muslim, or anything else. What mattered was skill, style, and beauty,” said De Giosa. “In the medieval Mediterranean world, art and architecture weren’t guarded as exclusive symbols; they were shared, admired, and repurposed across communities. Another important aspect is our focus on lesser-known, neglected case studies.”

The volume presents a captivating array of micro-historical case studies in which two of the world’s largest religions, Islam and Christianity, meet, engage, and intermingle during a historical epoch from which both faiths, still the world’s majority religions, can now draw meaningful lessons.

“In relation to our volume, the appeal of its case studies is almost self-evident,” the editors write, noting that the political turbulences following the 9/11 attacks, including the subsequent wars, events, and upheavals, have sparked significant academic interest in historical studies that explore the confrontation or coexistence of Islam and Christianity.

---

Method of Research

Case study

Coptic capital with Christian cross and other symbols at the Mosque of al-Nasir Muhammad in the Citadel in Cairo.

Credit

Sami Luigi De Giosa.

Silk samite with Islamic calligraphy lines the casket of Saints Pelagius and John the Baptist, possibly Iberia, eleventh to early twelfth century.

Credit

Museo de San Isidoro, record no. 3-089-002-00.

Detail, Andrea Mantegna, San Zeno Altarpiece, Verona, 1456–59, with St. John and St. Zeno both holding books with covers in the “Islamic style.” 

Credit

San Zeno Church, Verona.

Upper cover, Psalterium Davidis (Book of Psalms by David), 1480–90. The cover and binding exhibit Islamic traits.

Credit

Herzog August Bibliothek, Wolfenbüttel, Cod. Guelf 39, Aug. 4,19.5 × 13 cm.

 

Island haven for threatened koalas is a genetic ‘trap’ without intervention

Flinders University

FacebookXLinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

Kangaroo Island koalas have many more, and longer, stretches of identical DNA inherited from both parents. Scientists call these stretches runs of homozygosity, and they are a hallmark of inbreeding.

view more 

Credit: Flinders University

Kangaroo Island in South Australia is home to a large, mostly disease-free koala population which, at first glance, looks like a conservation success story.

However, new research from Flinders University shows that because the population started small, it carries a genetic legacy that may make it harder to survive future threats.

Using whole-genome sequencing, researchers compared Kangaroo Island koalas with mainland populations in Victoria and Queensland.

Despite their relatively high abundance on Kangaroo Island, these koalas have much lower genetic diversity and are much more inbred than koalas on the mainland.

The problem stems from their history. In the 1920s, fewer than two dozen koalas were moved from Victoria to Kangaroo Island to save the species after hunting and habitat loss nearly wiped them out. Those original koalas came from a population that was already small and genetically limited.

Today, koalas along Australia’s east coast are officially listed as endangered, with populations becoming smaller and more isolated due to forest clearing, bushfires, diseases, and road development.

In contrast, the koalas on Kangaroo Island have become a symbol of hope for the species, in spite of major bushfires which razed more than half of the island in 2019-20.

Lead author Dr Katie Gates says: “Kangaroo Island koalas are a successful conservation story in terms of population size. But their genetic health tells a different story. Their limited diversity and high inbreeding means they might struggle to adapt to future threats like disease or climate change.”

The Flinders University researchers found that Kangaroo Island koalas have many more, and longer, stretches of identical DNA inherited from both parents. Scientists call these stretches runs of homozygosity, and they are a hallmark of inbreeding.

The team also found that potentially harmful genetic variants were more often present in a double dose on Kangaroo Island koalas, increasing the chance that those variants are expressed in new offspring.

This pattern increases the risk of fertility and other developmental problems, consistent with several abnormalities found in captured koalas.

While the population has so far mostly resisted infectious diseases like chlamydia and koala retrovirus, its reduced genetic toolkit could leave it vulnerable to future outbreaks.

The researchers recommend proactive conservation management, including ‘genetic rescue’ – or the careful introduction of new koalas from genetically diverse mainland populations.

Senior author Professor Luciano Beheregaray says: “Kangaroo Island has the potential to remain an important conservation refuge for koalas. But without genetic management, this ‘ark’ could become a trap. Our work highlights the importance of ongoing genomic monitoring for species managed in isolation.”

The findings also carry a broader message for wildlife conservation: while islands and fenced reserves can provide immediate protection, they must be paired with strategies to bolster genetic diversity if they are to remain true havens for threatened species.

The article,  Conservation arks: genomic erosion and inbreeding in an abundant island population of koalas (2025)   by K Gates, J Sandoval-Castillo, JE Beaman, K Burke da Silva, R Saltré, K Belov, CJ Hogg, CJA Bradshaw and LB Beheregaray, has been published in Molecular Ecology DOI: 10.1111/mec.70097.

Acknowledgement: This work was supported by Australian Research Council, LP210100450.

 

The study found that potentially harmful genetic variants were more often present in a double dose on Kangaroo Island koalas, increasing the chance that those variants are expressed in new offspring.

Credit

Flinders University

---

Journal

Molecular Ecology

DOI

10.1111/mec.70097 

Article Title

Conservation arks: genomic erosion and inbreeding in an abundant island population of koalas

Article Publication Date

14-Sep-2025

 

Traditional herb boosts fish health and immunity, study reveals

KeAi Communications Co., Ltd.

Facebook

XLinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

Figure: The hypothetical mechanism of dietary inclusion of PFL to improve the immunity in the gut–liver axis. IEL, intestinal epithelial layer; LP, lamina propria layer; Th, T helper; GC, goblet cell; HSC, hepatic stellate cell. The underlined terms represent our findings, and the bold words represent the inferred biological meaning.

view more 

Credit: Xiaoqin Xia, et al

A groundbreaking study from the Chinese Academy of Sciences reveals how the traditional herb Picria fel-terrae (PFL) can significantly improve fish health. When added to fish feed at just 0.1% concentration for six weeks, the herb maintained healthy gut structure while reducing inflammation, a common problem in farmed fish.

"Our findings show this ancient herb can simultaneously protect intestinal health, balance immune responses, and improve metabolism," said Prof. Xiao-Qin Xia, lead researcher. "This could revolutionize how we maintain fish health in aquaculture without relying on antibiotics."

The research team made several key discoveries. PFL-treated fish maintained healthy gut villi structure while untreated fish developed atrophy. The herb increased protective mucus-producing cells by 30% and reduced harmful inflammation while boosting beneficial immune cells. When challenged with pathogens, fish receiving PFL showed better survival rates.

Surprisingly, the herb worked through multiple pathways, regulating genes involved in immunity, metabolism, and cell repair. It also restored healthy gut bacteria that are typically disrupted by plant-based feeds.

"This is one of the first comprehensive studies showing how a single natural compound can address multiple health challenges in aquaculture," Prof. Xia noted. The team used advanced techniques, including gene analysis, 3D imaging, and microbiome sequencing, to uncover these effects.

The findings, published in Water Biology and Security, come at a crucial time as the aquaculture industry seeks sustainable alternatives to antibiotics and ways to improve fish nutrition.

###

Contact the author: Prof. Xiaoqin Xia, Institute of Hydrobiology, Chinese Academy of Sciences. Email: xqxia@ihb.ac.cn

The publisher KeAi was established by Elsevier and China Science Publishing & Media Ltd to unfold quality research globally. In 2013, our focus shifted to open access publishing. We now proudly publish more than 200 world-class, open access, English language journals, spanning all scientific disciplines. Many of these are titles we publish in partnership with prestigious societies and academic institutions, such as the National Natural Science Foundation of China (NSFC).

 

---

Journal

Water Biology and Security

DOI

10.1016/j.watbs.2025.100452 

Method of Research

Experimental study

Subject of Research

Animals

Article Title

The effects of Picria fel-terrae Lour. on ameliorating hepatic metaflammation while modulating mucosal immunity in fish