Article
Chemistry, Multidisciplinary
Fang Li, Lu Yang, Ling Zou, Yonghui Wu, Chengbo Hu, Jian He, Xiaochao Yang
Summary: Ceria nanoparticles can mimic the activities of natural enzymes and their crystallinity is closely related to their SOD-like activity. Lower crystallinity can result in higher SOD-like activity in ceria nanoparticles.
Article
Chemistry, Multidisciplinary
Ayano Taniguchi, Yoshitaka Kumabe, Kai Kan, Masataka Ohtani, Kazuya Kobiro
Summary: Porous ceria was successfully synthesized through a unique solvothermal reaction, resulting in homogeneous and monodisperse spheres with a large surface area. The catalytic performance of the porous ceria exhibited superior and distinct reaction activity compared to commercial CeO2, attributed to the high concentration of Ce3+ and significant oxygen adsorption capacity.
Article
Chemistry, Physical
Aila O. Santos, Lara D. Martins, Jose Henrique S. Mezavila, Jilder D. P. Serna, Noemi R. Checca, Andre V. H. Soares, Caio Machado Fernandes, Eduardo A. Ponzio, Julio Cesar M. Silva, Odivaldo C. Alves
Summary: In this study, the temperature dependence of the magnetic properties of ceria nanoparticles with cubic morphology was systematically investigated. Magnetization measurements and electron paramagnetic resonance (EPR) spectroscopy revealed both ferromagnetic and paramagnetic behavior in CeO2 nanoparticles. The temperature dependence of the broad line in EPR spectra indicated a magnetic transition at approximately 50 K, which was attributed to the condensation of surface oxygen and the extinction of oxygen vacancies. This result further confirmed the relationship between oxygen vacancies and ferromagnetic behavior in CeO2 nanoparticles.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Nanoscience & Nanotechnology
Mingjie Huang, Yi Han, Wei Xiang, Chen Wang, Juan Mao, Tao Zhou, Xiaohui Wu, Han-Qing Yu
Summary: This study develops an ultrafast dehalogenation system that is dominated by O2 center dot- through molecular O2 activation by oxygen vacancy-rich CuO nanoparticles. The system shows high efficiency in degrading halogenated organic compounds, and the selectivity of O2 center dot- generation is enhanced through oxygen vacancy enrichment and the presence of carbonate species. This work provides a new opportunity for selective O2 center dot- generation for dehalogenation and other environmental applications through interfacial defect engineering.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Multidisciplinary
Anton L. Popov, Nadia M. Zholobak, Alexander B. Shcherbakov, Taisiya O. Kozlova, Danil D. Kolmanovich, Artem M. Ermakov, Nelli R. Popova, Nikita N. Chukavin, Ernest A. Bazikyan, Vladimir K. Ivanov
Summary: The toxic effects of cerium and fluoride species on human dental pulp stem cells and epithelial cells were studied. Cerium fluoride nanoparticles showed no cytotoxicity or genotoxicity to dental pulp stem cells and even increased cell proliferation and differentiation at certain concentrations. Furthermore, the formation of cerium fluoride provided protection against oral diseases.
Article
Chemistry, Physical
Lais Reis Borges, Anderson Gabriel Marques da Silva, Adriano Henrique Braga, Liane Marcia Rossi, Marco Aurelio Suller Garcia, Pedro Vidinha
Summary: Different surface energies of CeO2 nanowires and nanocubes affect the Pt distribution and interaction, leading to varying catalytic performance. The H-2-reduction treatment improves the catalysis of Pt/CeO2 nanowires, but does not surpass the nanocubes-based catalyst, highlighting the complex combination of material characteristics in determining catalyst performance.
Article
Nanoscience & Nanotechnology
Sizhe Li, Jie Yin, Hao Zhang, Kai A. I. Zhang
Summary: The oxidative formation of high value compounds using heterogeneous polymeric photocatalysts has become a valuable tool in catalysis. However, controlling the interaction between the active sites and oxygen molecules is challenging due to the large polymer backbone structure. In this study, a triazine-containing conjugated microporous polymer (CMP) with dual active sites was designed for molecular oxygen activation. Introducing fluorine atoms on the CMP backbone enhanced the adsorption and electron transfer of oxygen, efficiently generating superoxide radicals and singlet oxygen as active oxygen species. The photocatalytic activity, selectivity, and reusability of the CMP were demonstrated by the formation of benzothiazoles.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Biotechnology & Applied Microbiology
Wenlong Du, Pengfei Zhai, Shuai Liu, Yuanwei Zhang, Ling Lu
Summary: This study revealed that CcsA functions as a chaperone for SodA in A. fumigatus, and the conserved CXC motif within CcsA is crucial for its interaction with SodA and the oxidative stress response mediated by the CcsA-SodA complex. The findings provide new insights into how fungal pathogens adapt to oxidative stress via the CcsA-SodA complex.
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
(2021)
Article
Chemistry, Multidisciplinary
Jorn de Jong, Maxime A. Siegler, Sander J. Wezenberg
Summary: This study presents a type of macrocycle with stiff-stilbene-containing structure that can undergo photoinduced isomerization between (Z)- and (E)-isomers. The macrocycles can effectively form pseudorotaxane complexes with pyridinium halide axles, which can be tuned by varying the templating counteranion. However, the threading capability of axles is significantly reduced upon light-induced isomerization. Additionally, the axle component can dynamically relocate between the macrocycle and a secondary isophthalamide host, triggered by light irradiation.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Pablo G. Lustemberg, Zhongtian Mao, Agustin Salcedo, Beatriz Irigoyen, M. Veronica Ganduglia-Pirovano, Charles T. Campbell
Summary: Research has shown that cationic Ni atoms in clusters at step edges on the CeO2(111) surface are the most active sites for methane conversion reactions, with their small size and high Ni chemical potential contributing to their activity. Density functional theory calculations have clarified the reasons behind this observation, highlighting the importance of the size and morphology of supported Ni nanoparticles, strong Ni-support bonding, and charge transfer at step edges for high catalytic activity, particularly in the activation barrier for C-H bond cleavage during CH4 dissociative adsorption. This knowledge is expected to inspire the development of more efficient catalysts for these reactions.
Article
Multidisciplinary Sciences
Hao-Xin Liu, Jin-Ying Li, Xuetao Qin, Chao Ma, Wei-Wei Wang, Kai Xu, Han Yan, Dequan Xiao, Chun-Jiang Jia, Qiang Fu, Ding Ma
Summary: Constructing effective catalytic interfaces is crucial for improving catalytic performance. In this study, the authors utilized the stress of MoO3/gamma-Mo2N structure and the interaction between Pt and support to construct an effective catalytic interface for the low-temperature reverse water-gas shift reaction. By depositing isolated Pt atoms onto a thin layer of MoO3 surface, followed by reduction into MoOx and formation of Pt clusters, high-density Pt-n-O-v active sites were created, leading to enhanced catalytic activity.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Zhicheng Shi, Kai Li, Jieping Li, Yi Ding, Xuebin Zheng
Summary: Controlling the morphology of ceria nanoparticles allows for the regulation of their enzyme-like activities. The different morphologies of CeNPs exhibit distinct crystal facets, and the defects and energy band structures of these facets directly influence their catalytic activities. Adjusting the energy band structure to the midpoint of the catalytic half-reaction potentials can enhance catalytic efficiency.
JOURNAL OF NANOPARTICLE RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Tao Liu, Yuxin Chen, Yaming Hao, Jianxiang Wu, Ran Wang, Limin Gu, Xuejing Yang, Qiang Yang, Cheng Lian, Honglai Liu, Ming Gong
Summary: The strong synergy between borate and fluoride anions for water oxidation in neutral conditions was discovered in this study. The hierarchical arrangement of the anions at the electrode-electrolyte interface played a crucial role in this synergy, allowing for a significant enhancement of the water oxidation current. The use of the synergized electrolyte resulted in a low-cost and facilely synthesized Co(OH)(2) electrode with outstanding performance and durability.
Article
Chemistry, Physical
Zhenzhen Wang, Xiaomei Shen, Xingfa Gao
Summary: Using density functional theory calculations, the study reveals the crucial role of oxygen vacancies in nanoceria catalysis and the dependence of nanoceria activity on the presence of oxygen vacancies. The results help explain the enzyme-like catalytic activities of nanoceria and may guide the future design of nanoceria-based enzyme mimics.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Multidisciplinary
Tao Wang, Yiru Li, Erik Jan Cornel, Chang Li, Jianzhong Du
Summary: A combined antioxidant-antibiotic therapy was proposed using polymer vesicles loaded with ciprofloxacin and decorated with ceria nanoparticles, which showed high superoxide dismutase mimetic activity and enhanced antibacterial activity. In vivo treatment on a diabetic mice model demonstrated that the CIP-Ceria-PVs effectively healed infected diabetic wounds within 14 days.
Article
Multidisciplinary Sciences
Ilaria Barlocco, Luis A. Cipriano, Giovanni Di Liberto, Gianfranco Pacchioni
Summary: This study investigates the impact of different exchange-correlation functionals on the catalytic activity of single atom catalysts in hydrogen and oxygen evolution reactions. The results show that the choice of functional can lead to significant deviations in the predicted activity for different transition metals.
ADVANCED THEORY AND SIMULATIONS
(2023)
Article
Nanoscience & Nanotechnology
J. Alejandro De Sousa, Raphael Pfattner, Diego Gutierrez, Kilian Jutglar, T. Bromley Stefan, Jaume Veciana, Concepcio Rovira, Marta Mas-Torrent, Bruno Fabre, Nuria Crivillers
Summary: The preparation of monolayers based on an organic radical and its diamagnetic counterpart has been investigated on hydrogen-terminated silicon surfaces. The monolayers exhibit a characteristic diode behavior in solid-state metal/monolayer/semiconductor junctions, which is influenced by the electronic characteristics of the organic molecule. The presence of the radical significantly enhances the rectification ratio and photosensitivity of the junction.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Miguel Recio-Poo, Angel Morales-Garcia, Francesc Illas, Stefan T. T. Bromley
Summary: In this study, the interrelation between crystallinity, surface hydroxylation, and electronic structure in titania nanoparticles (NPs) was investigated using density functional theory-based calculations. The results showed that the local coordination environments of the atoms in annealed non-crystalline NPs became similar to those in faceted crystalline anatase NPs with increasing hydroxylation. Highly hydroxylated annealed NPs also exhibited similar electronic energy gaps and band edge orbital characters to crystalline anatase NPs. These findings suggest that the anatase crystal structure may not be essential for TiO2 NP applications, and crystal-like NPs could exist in other nanomaterials.
Article
Nanoscience & Nanotechnology
Farahnaz Maleki, Giovanni Di Liberto, Gianfranco Pacchioni
Summary: In this work, the pH- and facet-dependent surface chemistry of TiO2/water interfaces was studied using ab initio molecular dynamics simulations. Acid-base equilibrium constants were determined at the interface, allowing for estimation of the pH at the point of zero charge, an important experimental observable. The amount of H+, OH-, and adsorbed H2O species on the surfaces was predicted based on simulated equilibrium constants, providing insights into water splitting semi-reactions. The complex morphology of TiO2 particles was approximated by considering different surfaces.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
Marti Lopez, Kai S. Exner, Francesc Vines, Francesc Illas
Summary: Both experimental and theoretical studies have shown that the MXene family has promising capabilities for the hydrogen evolution reaction (HER). However, the theoretical approach has relied on thermodynamic descriptors, while experimental studies have focused on kinetic information. This study aims to bridge the gap between theory and experiments by exploring HER pathways on V2C (0001) MXene and constructing free-energy diagrams to simulate Tafel plots. The results suggest that the V2C-H surface is kinetically favorable for the HER.
JOURNAL OF CATALYSIS
(2023)
Article
Chemistry, Physical
Carlos Jimenez-Orozco, Elizabeth Florez, Francesc Vines, Jose A. Rodriguez, Francesc Illas
Summary: The ethylene hydrogenation catalyzed by MoCy nanoparticles was studied using density functional theory methods and several models. The effect of hydrogen coverage was examined in detail, and it was found that ethylene hydrogenation is feasible on specific MoCy nanostructures under different hydrogen coverages. The results also showed that C2H4 adsorption is feasible in a certain temperature and pressure range. The findings provide insights into the catalytic behavior of MoCy catalysts and offer a basis for future experimental studies.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Eleonora Romeo, Francesc Illas, Federico Calle-Vallejo
Summary: Incorporating solvent-adsorbate interactions is crucial in models of aqueous (electro)-catalytic reactions. Existing techniques are either computationally demanding or inaccurate. Microsolvation provides a trade-off between accuracy and computational expenses. This study presents a method to rapidly outline the first solvation shell of adsorbed species on transition-metal surfaces and evaluate their solvation energy. Dispersion corrections are generally not required, but caution is needed when water-water and water-adsorbate interactions are similar in magnitude.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Nestor Garcia-Romeral, Angel Morales-Garcia, Francesc Vines, Iberio de P. R. Moreira, Francesc Illas
Summary: The electronic ground state of Ti2C MXene was determined using density functional theory calculations, showing a magnetic ground state with antiferromagnetically coupled ferromagnetic layers. A spin model consistent with the nature of the chemical bond was presented, and the relevant magnetic coupling constants were extracted from energy differences using a mapping approach. The estimated Neel temperature is approximately 220 +/- 30 K, suggesting potential applications in spintronics and related fields.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Isaac Alcon, Jordi Ribas-Arino, Iberio de P. R. Moreira, Stefan T. Bromley
Summary: Two-dimensional conjugated polymers (2DCPs) are organic 2D materials composed of arrays of carbon sp(2) centers connected by pi-conjugated linkers, and they are gaining attention for their potential applications in device technologies. In this study, we use first-principles calculations to predict the electronic and magnetic properties of a new class of hexagonally connected neutral mixed-valence 2DCPs. We find that these materials exhibit emergent superexchange-mediated antiferromagnetic interactions, making them a highly promising platform for the realization of all-organic quantum materials.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Multidisciplinary Sciences
Miquel Lopez-Suarez, Genis Lleopart, Raul Morales-Salvador, Iberio de P. R. Moreira, Stefan T. Bromley
Summary: In this study, the mechanical and electronic response of sp(2)-based two-dimensional materials under in-plane compression was investigated using first principles density functional theory-based calculations. It was found that two carbon-based graphynes, alpha-graphyne and gamma-graphyne, exhibit out-of-plane buckling under modest in-plane biaxial compression. This buckling is energetically more stable than in-plane scaling/distortion and significantly reduces the in-plane stiffness of the materials. Moreover, the buckling also leads to in-plane auxetic behavior and modulates the electronic band gap.
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
(2023)
Article
Chemistry, Physical
Pablo Lozano-Reis, Hector Prats, Ramon Sayos, Francesc Illas
Summary: The reverse water-gas shift (RWGS) reaction on a bifunctional catalyst is studied using a combination of density functional theory (DFT) calculations, statistical thermodynamics, and kinetic Monte Carlo (kMC) simulations. The limitations of DFT predictions in including the effect of coverage of surface species are evident, as they do not match the outcome of kMC simulations. However, the kMC simulations show remarkable agreement with experimental data, demonstrating their ability to accurately describe the complex chemistry of the RWGS reaction on a bifunctional catalyst.
JOURNAL OF CATALYSIS
(2023)
Article
Chemistry, Physical
Elena Remesal, Angel Morales-Garcia, Francesc Illas
Summary: Through density functional theory-based calculations, we found that interstitial N doping promotes the formation of oxygen vacancies and leads to a more significant reduction in the energy gap compared to N substitution of oxygen atoms.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Josei A. Rodriguez, Carlos Jimenez-Orozco, Elizabeth Florez, Francesc Vines, Francesc Illas
Summary: The studies in this Perspective demonstrate the utility of transition metal carbide (TMC) nanoparticles in activating and trapping molecules such as H-2, CH4, and CO2, which are essential in C-1 chemistry and greenhouse gas conversion. By combining experimental and theoretical approaches, the physical and chemical properties of these TMC systems have been elucidated, revealing their unique behavior and structures at the nanoscale. Theoretical and experimental investigations of supported and unsupported TMC nanoparticles are presented, along with an analysis of current challenges and potential applications.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Sascha T. Zeegers, Joan Marinoso Guiu, Francisca Kemper, Jonathan P. Marshall, Stefan T. Bromley
Summary: Quantum chemical calculations are used to obtain the mid-infrared optical properties of silicate nanoparticles, and a model is developed to predict the spectral appearance of mixtures of bulk and nanoparticle silicates. The predictions suggest that the James Webb Space Telescope (JWST) can detect 3-10% nanosilicate content with its mid-IR instrument (MIRI).
FARADAY DISCUSSIONS
(2023)
Article
Chemistry, Physical
Ilaria Barlocco, Giovanni Di Liberto, Gianfranco Pacchioni
Summary: Single Atom Catalysts (SACs) bridge the gap between homogenous and heterogenous catalysis and show promise in various chemical reactions, including water splitting. This study focuses on SACs embedded in Covalent Organic Frameworks (COFs) and investigates their reactivity in Hydrogen and Oxygen Evolution Reactions (HER and OER, respectively) using density functional theory (DFT). The results reveal the formation of unique intermediates and shed light on the reaction mechanism, providing valuable insights for the design of novel catalytic materials.