Article
Chemistry, Multidisciplinary
Wei Ran, Andreas Walz, Karolina Stoiber, Peter Knecht, Hongxiang Xu, Anthoula C. Papageorgiou, Annette Huettig, Diego Cortizo-Lacalle, Juan P. Mora-Fuentes, Aurelio Mateo-Alonso, Hartmut Schlichting, Joachim Reichert, Johannes Barth
Summary: The atomically precise engineering of N-doped molecular graphene nanoribbons (GNRs) is achieved by combining multistep solution synthesis and mass-selected ion beam deposition on surfaces. This method allows for the controllable production of single GNRs, which can be further processed using on-surface synthesis protocols.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Engineering, Environmental
Christos Chatzilias, Eftychia Martino, Sotirios Tsatsos, Georgios Kyriakou, Alexandros Katsaounis, Constantinos G. Vayenas
Summary: In this study, the kinetic mechanism of CO2 hydrogenation was investigated using a scaled up electropromoted reactor loaded with nine Ru/YSZ/Au electrochemical cells. The results show that the partial pressures of H2 and CO2 have a significant impact on the product distribution and reaction rate. Additionally, the experiment validates the charge transfer behavior during the electrochemical promotion process.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Energy & Fuels
Juin Yau Lim, Adrian Chun Minh Loy, Hatem Alhazmi, Bridgid Chin Lai Fui, Kin Wai Cheah, Martin J. Taylor, Georgios Kyriakou, Chang Kyoo Yoo
Summary: The catalytic dry reforming process was studied using a novel framework for determining optimal reaction configurations and pathways. Machine learning was used to analyze the impact of various parameters on the process, leading to the identification of best conditions for different hydrocarbons on Pt(111) and Ni(111) surfaces. Additionally, the energy profile of selective reaction pathways and activation energy for bond dissociation were analyzed, revealing lower Ea on Pt(111) compared to other surfaces.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2022)
Article
Electrochemistry
B. Hasa, E. Martino, S. Tsatsos, J. Vakros, G. Kyriakou, A. Katsaounis
Summary: Pt-based electrocatalysts, both monometallic and bimetallic, synthesized using graphene as the support, showed improved performance for the electrocatalytic oxidation of methanol. The interaction between metal particles and carbon support, as well as the surface structure and electronic interaction, played crucial roles in the electrocatalytic activity.
JOURNAL OF APPLIED ELECTROCHEMISTRY
(2022)
Article
Biotechnology & Applied Microbiology
Berta Diez, W. Joseph A. Homer, Laura J. Leslie, Georgios Kyriakou, Roberto Rosal, Paul D. Topham, Eirini Theodosiou
Summary: Tailor-made biocompatible electrospun mats showing antimicrobial behaviour were successfully created through altering the concentration of chemical cross-linkers. This flexible approach offers the potential of matching the dressing to the wound type and offering a more targeted solution to wound management.
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
(2022)
Article
Chemistry, Physical
Dimitrios Zagoraios, Nikoletta Kokkinou, Georgios Kyriakou, Alexandros Katsaounis
Summary: The present study demonstrates the in situ formation and stabilization of nickel oxide on an oxygen ion conductor/solid electrolyte using electrochemistry. It also shows that electrochemical promotion of catalysis (EPOC) and electrochemical oxidation can enhance the activity of the reverse water gas shift (RWGS) reaction. The results provide a new approach for in situ catalyst activation and regeneration in the modern heterogeneous catalysis industry.
CATALYSIS SCIENCE & TECHNOLOGY
(2022)
Article
Chemistry, Physical
Sotirios Tsatsos, John Vakros, Spyridon Ladas, Xenophon E. Verykios, Georgios Kyriakou
Summary: A series of WO3/TiO2 catalysts were synthesized and characterized for the NO selective catalytic reduction (SCR) with NH3. The interfacial electron transfer between WO3 and TiO2 was studied, and its relationship with the acid-base properties of the catalytic surface and electronic structure modification was defined. The results showed that altering the dispersion and size of the WO3 nanostructures led to changes in titania's surface electron distribution, which affected the catalytic activity. It was found that higher WO3 loading on TiO2 resulted in stronger electronic interaction and higher catalytic activity due to increased surface electron density and enhanced surface basicity.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Chemistry, Multidisciplinary
Peter Knecht, Dennis Meier, Joachim Reichert, David A. Duncan, Martin Schwarz, Johannes T. Kuechle, Tien-Lin Lee, Peter S. Deimel, Peter Feulner, Francesco Allegretti, Willi Auwaerter, Guillaume Medard, Ari Paavo Seitsonen, Johannes Barth, Anthoula C. Papageorgiou
Summary: Ru-porphyrins serve as pedestals for the assembly of N-heterocyclic carbenes (NHCs) on solid surfaces. A phenomenon of transferring Ru-porphyrin molecules from the surface to the next layer can be observed upon deposition of a simple NHC ligand on a close-packed Ru-porphyrin monolayer. The uptake of NHC induces a rearrangement of the molecular layer, which can be reversed by thermal desorption of the NHC ligand. Understanding such mass transport processes is crucial for surface functionalization with carbenes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Christos Chatzilias, Eftychia Martino, Constantinos G. Vayenas, Georgios Kyriakou, Alexandros Katsaounis
Summary: This study demonstrates a method to effectively promote catalytic reactions using limited power generated by low-temperature fuel cells, reducing energy consumption and environmental impact. By designing a novel low-temperature fuel cell reactor and utilizing internal power, electrochemical promotion of CO2 hydrogenation has been achieved.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
Article
Chemistry, Analytical
Georgios Bampos, Sotirios Tsatsos, Georgios Kyriakou, Symeon Bebelis
Summary: A series of bimetallic and monometallic electrocatalysts were prepared and tested for their hydrogen oxidation reaction activity. Among the Pd-based electrocatalysts, 7.5 wt% Pd-2.5 wt% Ag/C showed the highest activity, attributed to the electronic interaction between Ag and Pd. The findings have implications for improving the efficiency of hydrogen oxidation reactions.
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Physical
Sotirios Tsatsos, Georgios Kyriakou
Summary: The deposition of Cu on a stepped Ni(119) surface was studied using experimental and computational methods. Cu was found to grow in a layer-by-layer mode at ambient temperature and primarily occupy 4-fold hollow sites below the step edge. The adsorption of CO was quantitatively altered by the presence of Cu, which was attributed to the geometric and electronic effects of the Cu-Ni interaction.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Review
Thermodynamics
Adrian Chun Minh Loy, Sin Yong Teng, Bing Shen How, Xixia Zhang, Kin Wai Cheah, Valeria Butera, Wei Dong Leong, Bridgid Lai Fui Chin, Chung Loong Yiin, Martin J. Taylor, Georgios Kyriakou
Summary: The emergence of single atom sites as a frontier research area in catalysis has attracted extensive interest, especially for energy, environmental, and chemicals production. Single atom catalysts (SACs) have shown remarkable performance in various catalytic reactions, demonstrating high selectivity, long lifespan, stability, and high atomic metal utilization efficiency. This review provides insights on the development and achievements of SACs, including chronological progress, recent advances in synthesis, characterization techniques, applications, environmental and economic aspects, and current challenges and future prospects.
PROGRESS IN ENERGY AND COMBUSTION SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Mohammed J. Islam, Marta Granollers Mesa, Amin Osatiashtiani, Martin J. Taylor, Mark A. Isaacs, Georgios Kyriakou
Summary: By diluting the Pd content in the alloy, the reaction activity of Cu nanoparticles can be accelerated, leading to increased time for the cascade conversion and higher selectivity towards butanol. Compared to bulk Cu/Al2O3 and Pd/Al2O3 catalysts, the single atom alloy catalysts showed a significant increase in conversion rate. These findings suggest that fine-tuning the dilution of PdCu single atom alloy catalysts can provide cost-effective and sustainable alternatives to traditional monometallic catalysts.
Article
Engineering, Environmental
A. Rontogianni, N. Chalmpes, E. Nikolaraki, G. Botzolaki, A. Androulakis, A. Stratakis, P. Zygouri, D. Moschovas, A. Avgeropoulos, M. A. Karakassides, D. P. Gournis, S. Tsatsos, G. Kyriakou, N. K. Boukos, P. Panagiotopoulou, I. V. Yentekakis
Summary: CO2 methanation is a crucial area of research due to the urgent need to control and recycle CO2 emissions for environmental and energy purposes. This study investigates the reaction over mono- and bi-metallic RuNi catalysts supported on mesoporous MCM-41 materials. The results show that mono-metallic Ru catalysts outperform their Ni counterparts, and bi-metallic RuNi catalysts are inferior to mono-metallic Ru but better than mono-metallic Ni. The efficiency of mono-metallic Ni catalysts in CO2 methanation is highly dependent on the catalyst preparation method, with one-pot synthesis being ineffective and impregnation yielding efficient catalysts. By forming core(Ru)-shell(Ni) nano-configurations, small amounts of Ru can induce redispersion of stabilized large Ni crystallites, which is important for practical applications. Detailed characterizations and studies on kinetics and in-situ DRIFTS provide a convincing explanation for these novel findings.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Dennis Meier, Benedikt Schoof, Jinhua Wang, Xuesong Li, Andreas Walz, Annette Huettig, Hartmut Schlichting, Frederic Rosu, Valerie Gabelica, Victor Maurizot, Joachim Reichert, Anthoula C. Papageorgiou, Ivan Huc, Johannes Barth
Summary: Aromatic foldamers show promise for molecular recognition and molecular machinery applications, requiring defect-free, 2D-crystalline monolayers. To achieve this, submonolayers were prepared on Ag(111) surface using electrospray controlled ion beam deposition (ES-CIBD) in ultra-high vacuum (UHV). Real-space single-molecule imaging with scanning tunnelling microscopy (STM) unambiguously identified the unfolded state on the surface, which assembled into regular structures.
CHEMICAL COMMUNICATIONS
(2022)