Artículos (Química Inorgánica)

URI permanente para esta colecciónhttps://hdl.handle.net/11441/10919

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From Single Atoms to Nanoparticles: Pathways Toward Efficient and Durable Pt/TiO2 Photocatalysts
(Wiley, 2026-06-02) Delgado, Juan José; Bu, Enqi; Han, Yaning; López Cartes, Carlos; Calatayud, Mónica; Pan, Huiyan; Chen, Xiaowei; Química Inorgánica; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Agencia Estatal de Investigación. España; European Union (UE)
We develop a simple and scalable strategy to control the size of Pt species on anatase TiO2 nanosheets (TNS), ranging fromatomically dispersed single atoms (SAs) to nanoparticles (NPs). The method relies on photodeposition, where the temperatureregulates the adsorption of the Pt precursor and determines whether Pt is stabilized as isolated atoms or agglomerated particles.Ethanol photoreforming under simulated sunlight is used to evaluate catalytic performance and stability. At low light intensity, SA-rich samples exhibit the highest apparent activity and stable performance. However, post-reaction characterization reveals thatPt atoms migrate and agglomerate into clusters, indicating that activity alone cannot be taken as evidence of atomic stability.At higher light intensities, SA-rich samples deactivate rapidly due to accelerated Pt coalescence, while larger particles showcomparatively greater stability. The results indicate distinct sintering pathways: dissolution–redeposition dominates in liquid-phase reactions, whereas surface migration is prevalent in gas-phase conditions. Thermochemical treatments further modulatePt speciation: oxidation preserves SAs, whereas reduction induces agglomeration and preferential migration to the {101} facets,where Pt efficiently traps electrons and sustains hydrogen evolution. This study highlights how precursor adsorption, reactionenvironment, and post-treatments govern the structural evolution of Pt, providing design guidelines for durable single-atomphotocatalysts
One-step electrosynthesis of nanostructured Mn-V oxides with tunable redox characteristics
(Elsevier, 2026-07-01) Cabello-Illanes, Carmen; Torres-Barrera, Joaquín; Centeno, Miguel Ángel; Ivanova, Svetlana; Domínguez Leal, María Isabel; Martínez Tejada, Marcela; García-Dalí, Sergio; Química Inorgánica; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Agencia Estatal de Investigación. España
The rational design of nanostructured mixed-metal oxides through scalable and controllable fabrication methods remains a central challenge in nanomaterials science. In this work, we present a one-step, substrate-free electrosynthesis strategy that enables the direct formation of nanostructured Mn-V mixed oxides with tunable physicochemical characteristics. By systematically adjusting the applied current and precursor ratios, the method provides precise control over phase composition, crystallite size within the nanoscale regime, degree of amorphous vs. crystalline order, and textural parameters, allowing access to material architectures that are not attainable through conventional wet-chemical or high-temperature routes. A series of MnO oxides, as well as V 2 O 5 2 and Mn-V mixed for comparative purposes, were prepared under galvanostatic conditions without any further thermal treatment. Pure MnO 2 samples exhibited a mixture of ε- and γ-phases, with lamellar morphologies and outstanding surface areas. However, the incorporation of vanadium induced significant structural and morphological changes, including amorphization and the formation of V-based crystalline domains at higher loadings. Furthermore, catalytic tests showed that all materials achieved complete glucose conversion, while the Mn-V oxides significantly improved selectivity towards formic acid. Specifically, the MnV_5:1 sample exhibited the best performance, along with a notable suppression of CO 2 formation. The enhanced performance could be attributed to a synergistic Mn-V redox interaction that promotes controlled oxidation pathways and stabilizes intermediates. These findings demonstrate the potential of electrosynthesis as a tunable method, additionally offering sustainability, time-efficiency, cost-effectiveness, and reproducibility, for developing advanced and promising sustainable materials.
El modelo Push-Pull como estrategia de activación y estabilización molecular
(Real Sociedad Española de Química, 2025) Corona De Leaniz, Helena; Hidalgo Reinoso, Nereida; Pérez Jiménez, Marina; Cruz Martínez, Felipe de la; Campos Manzano, Jesús; Química Inorgánica
En este trabajo revisamos el concepto de Push-Pull (donador-aceptor) como estrategia para activación de moléculas inertes o para la estabilización de fragmentos altamente reactivos. Este modelo se basa en la combinación de un centro rico y un centro pobre en electrones que, de manera concertada, son capaces de donar (push) y retirar (pull) densidad electrónica de otro fragmento molecular. En esta perspectiva se describen diversos ejemplos que demuestran el interés y aplicabilidad de esta estrategia, incluyendo tanto sistemas que permiten activar moléculas poco reactivas como CO2 o N2, como otros que permiten la estabilización de fragmentos muy reactivos como LiH o LiMe.
Multidisciplinary science funding is more than ever a planetary priority: Reflections from the Make Our Planet Great Again (MOPGA) program
(Public Library of Science, 2026-03-11) Richards, Christina L.; Ervens, Barbara; Parmesan, Camille; Amato, Pierre; Andrade, Christhel; Asatryan, Gayane; Balaji, Venkatramani; Ballantyne, Ashley; Rivada Wheelaghan, Orestes; Zuerch, Michael; Química Inorgánica
Global change poses “wicked problems” that have become ever more complex, pervasive, and damaging. Developing innovative solutions increasingly require diverse research approaches. The Franco-German Make Our Planet Great Again (MOPGA) program was designed to create a unique international network of top-level research, from fundamental to solution-oriented projects. MOPGA stands out from other large research initiatives by focusing not on a singular central research challenge but on facilitating multidisciplinary interactions between traditionally separated fields. MOPGA recognized that social, natural and engineering sciences share a unifying aim to address global change. In addition to addressing timely and innovative research questions within disciplines, MOPGA worked to improve communicationacross disciplines via annual meetings for all laureates and their research groups, scientific board exchanges, and public online seminars. Drawing on our MOPGA experiences, we discuss how such exchanges should be extended to meet the needs identified by the scientific community, international policy-makers, and regional stakeholders. In the current political landscape of scientific suppression and heightened mistrust in scientific expertise, the need for such bold, independent and collaborative scientific initiatives is greater than ever.
RhIII and IrIII complexes bearing NNO-heteroscorpionates and their application in catalytic transfer hydrogenation
(RSC, 2022-09-23) Cerón-Castelán, J. E.; Salazar-Pereda, V.; González-Montiel, S.; Mendoza-Espinosa, D.; Castro-Osma, J. A.; López Santos, Laura; Gómez-Bonilla, M. A.; Sandoval-Chávez, C. I.; Química Inorgánica
The equimolar treatment of the bis(pyrazol-1-yl)-phenylethanol ligand with [M(Cl)3(H2O)3] precursors has been employed to obtain novel NNO-heteroscorpionate rhodiumIII (1) and iridiumIII (2) complexes. The structural fetures of 1 and 2 were determined by spectroscopic methods in solution and X-ray crystallography in solid state. Complexes 1 and 2 are efficient catalysts for the transfer hydrogenation of ketones and aldehydes under low catalyst loadings.
Tuning the Photoelectrochemical Properties of Ti/W-Modified PCN-222 Using Charge-Selective Interfaces
(Amer Chemical SOC, 2026) Expósito-Gálvez, Juan Carlos; Vattier Lagarrigue, María Florencia; Pedrosa, José María; Carrillo Carrión, Carolina; Oskam, Gerko; Química Inorgánica; Junta de Andalucía; Ministerio de Ciencia e Innovación (MICIN). España; Agencia Estatal de Investigación. España; European Union (UE); Universidad Pablo de Olavide
Metal−organic frameworks (MOFs) have attracted growing interest for photoelectrochemical (PEC) applications, including visible-light photocatalysis, CO2 reduction, and hydrogen evolution, owing to their structural tunability and hybrid inorganic−organic nature. The Zr-based porphyrinic framework PCN-222 combines strong visible light absorption from its porphyrin linkers with robust Zr6 clusters that act as structural and electronic backbones. Here, we report a modular strategy to tailor and optimize the PEC behavior of PCN-222 through postsynthetic metal-node substitution with Ti, pore encapsulation of phosphotungstic acid (PTA), and integration with charge-selective interfaces. The resulting PCN-222 materials exhibit photoelectrochemical activity across the entire visible range. Whereas pristine PCN-222(Zr) exhibits photocathodic behavior (photoelectron transfer to the solution and photohole collection at the FTO substrate), partial substitution of Zr with Ti inverts the current to photoanodic. Encapsulation of PTA further enhances the anodic photocurrent due to its electrocatalytic properties. Furthermore, charge-selective TiO2 and NiOx interlayers deposited between the FTO substrate and the MOF films enable selective extraction of photoelectrons or holes, respectively. This strategy results in a significant photocurrent enhancement, which can be attributed to effective competition of charge extraction and recombination. For PCN-222(Zr), the cathodic photocurrent increases by a factor of 7 using a NiOx interlayer, while the current switches to photoanodic upon TiO2 integration, illustrating the importance of efficient charge extraction. Similarly, the current direction is reversed to photocathodic for PCN-222(Zr/Ti) and PCN-222(Zr/Ti/W) when using NiOx. We discuss the interfacial charge extraction, charge transfer and trapping mechanis
Synergistic valorization of sewage sludge and lignin-rich lignocellulose via activated carbon-mediated Co-HTC: Enhancing hydrochar quality and its pyrolysis performance
(Elsevier, 2026) Rizwan, Muhammad; Leghari, Asma; Mansoor, Adil; Sadiq, Hammad; Ali, Muhammad Frayad; Wang, Mingzhi; Song, Yueqin; Nawaz, Muhammad Asif; Zhou, Xiaolong; Química Inorgánica; Ministerio de Ciencia e Innovación (MICIN). España
This study provides mechanistic insights into the role of rice-husk-derived activated carbon (AC:Y, 5–25 wt%) during co-hydrothermal carbonization (co-HTC) of sewage sludge (SS) and lignin-rich lignocellulose (LC:X, 5–25 wt%) at 200 ◦C for 60 min, followed by pyrolysis of the resulting hydrochars (HCs) between 500 ◦C-900 ◦C. Comprehensive characterization (FTIR, Raman, XPS, BET, SEM, TGA) of HC revealed that Y significantly enhanced its fuel quality and structural re-ordering. The optimized sample (SS-5X-5Y) showed higher carbon content (47.51 ± 0.092 %) and higher heating value (HHV:18.67 ± 0.038 MJ⋅kg⁻¹), and SS-25X-25Y demonstrated reduced ash content (24.60 ± 0.067 %) compared to SS-X alone. FTIR confirmed the presence of C=O (~1700 cm⁻¹), aromatic C=C (~1590 cm⁻¹), C–O (1200–1050 cm⁻¹), and S=O (~1100–1050 cm⁻¹) functionalities. Raman (ID/IG ↓ from 0.60 to 0.47) and XPS (C–C up to 78 %) indicated enhanced aromatic condensation and deoxygenation induced by Y. Pyrolytic products indicated that Y-mediated HCs promoted syngas-rich products, achieving 33–35 vol% H₂ and 45–49 vol% CO at 900 ◦C. This study establishes a robust framework for future investigation, particularly long-term combustion/gasification evaluations and detailed leaching behavior analysis, which will further validate the environmental stability, operational reliability, and broader techno-economic potential of Y-mediated HCs.
Spectroscopy-guided optimization of copperbased catalysts for low-temperature CO2 recycling to CO
(Royal Society of Chemistry, 2026-01-30) Blay Roger, José Rubén; Blay, Vincent; Torres Sempere, Guillermo; García Moncada, Nuria; Ramírez Reina, Tomás; Lacroix, Bertrand; Bobadilla Baladrón, Luis Francisco; Odriozola Gordón, José Antonio; Química Inorgánica; Física Aplicada I; Ministerio de Ciencia e Innovación (MICIN). España; Junta de Andalucía
The reverse water–gas shift (RWGS) reaction provides a sustainable route for CO2 valorization by producing CO, a key intermediate for various industrial applications. Its endothermic nature and the competition with Sabatier reaction impose a practical challenge on the design of low and medium temperature RWGS catalysts thus hampering its integration with downstream units. In this study, we investigate the design and optimization of Cu-based materials for low-temperature RWGS. A series of Cu/TiO2 catalysts were synthesized and characterized using operando UV-vis, DRIFTS, and NAP-XPS spectroscopies. These studies allow us to prioritize the most promising catalyst and to derive key insights into surface intermediates, such as the formation of acrolein as a major coke precursor. These insights enable us to optimize the catalyst and mitigate deactivation through coking. Pt doping is shown to be particularly effective in reducing coke deposition, thus enhancing the long-term stability and overall catalyst's performance. Our multicomponent PtCuK@ catalyst demonstrated superior activity, selectivity, and regenerability under extended operation, opening new horizons for advanced RWGS catalysts targeting industrial CO2 utilization. This work also provides a comprehensive framework for enhancing catalyst durability and anti-coking strategies in sustainable CO2 valorization processes.
Analysis of conductivity in 8YSZ ceramics during AC-flash processes: A two-barrier ionic transport model approach
(Elsevier, 2026) Molina Molina, Sandra; Manchón Gordón, Alejandro F.; Perejón Pazo, Antonio; Sánchez Jiménez, Pedro Enrique; Pérez Maqueda, Luis Allan; Física de la Materia Condensada; Química Inorgánica; Junta de Andalucía
This work offers a systematic study of the electrical conductivity in dense 8 mol% yttria-stabilized zirconia (8YSZ) during non-isothermal and isothermal AC-flash conditions under a fixed applied voltage. Conductivity data were interpreted using a two-barrier ionic transport model which is able to capture the non-Arrhenius behavior commonly found for 8YSZ. The analysis of the conductivity evolution indicates that AC-flash in 8YSZ may be understood as a time-dependent breakdown process where the field exposure duration plays a critical role, driven by similar charge transport mechanisms regardless of the employed methodology. A characteristic sequence of electrical resistance degradation, previously described for 8YSZ subjected to DC fields, is also observed under AC fields, suggesting the involvement of partial discharge mechanisms and charge accumulation effects in the formation of conductive paths eventually leading to the flash event. These findings highlight the limitations of time-independent conductivity models to fully describe AC-flash processes in 8YSZ ceramic
An Unusually Short Unsupported Pt─Pt Bond in a 24-Electron Diplatinum(0) Complex With Fluorinated Bis(phosphonite) Ligands
(Wiley, 2026) Alcaide, María M.; Álvarez, Eleuterio; López Serrano, Joaquín; Peloso, Riccardo; Química Inorgánica; Ministerio de Economia, Industria y Competitividad (MINECO). España; Junta de Andalucía; Agencia Estatal de Investigación. España; European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER)
We report the synthesis and characterization of a 24-electron diplatinum(0) complex stabilized by two fluorinated terphenylphos-phonite ligands. This complex features an exceptionally short, unsupported Pt0─Pt 0 bond (2.6348 Å), the shortest structurallyauthenticated to date. Single crystal X-ray diffraction reveals a centrosymmetric structure with highly distorted linear coordina-tion and pronounced electronic and coordinative unsaturation. Energy Decomposition (EDA) and Natural Orbital for ChemicalValence (NOCV) Analyses indicate that, while the main attractive component of the Pt─Pt interaction is electrostatic, the orbitalcontribution is also instrumental in the formation of the complex, which is facilitated by the bending of the P–Pt–Pt–P core.Noncovalent Interaction (NCI) and Atoms in Molecules (AIM) analyses support the presence of a Pt─Pt bond and reveal a rolefor the terphenyl substituents of the ligands in the stability of the 24-electrons dimer. Reaction of this species with 1,5-cyclo-octadiene affords a new dinuclear species featuring distorted trigonal planar coordination at each platinum atom. These findingsprovide new insights into metallophilic interactions in closed-shell d10 systems and underscore the ability of bulky phosphoniteligands to stabilize low-coordinate platinum(0) species with unconventional bonding motifs.
Evaluation of Pt/TiO2-Nb2O5 systems in the photocatalytic reforming of glucose for the generation of H2 from industrial effluents
(Elsevier, 2024) Lara Sandoval, Adriana Elizabeth; Serafin, Jarosław; Murcia Mesa, Julie Joseane; Rojas Sarmiento, Hugo Alfonso; Hernández Niño, Jhon Sebastian; Llorca, Jordi; Navío Santos, José Antonio; Hidalgo Lõpez, María Carmen; Química Inorgánica; Fondo Nacional de Financiamiento para la Ciencia, la Tecnología y la Innovación (FCTel)
Different Pt-TiO2-Nb2O5 systems were synthesized and studied in the photocatalytic reforming of glucose for the generation of H2. The physicochemical properties of the synthesized photocatalysts were analyzed using different characterization techniques from which it was found that fluoridation and sulphation have different effects on the oxides under study such as a protective effect on the crystalline phase in anatase, and greater response in the visible region of the electromagnetic spectrum. The addition of fluorine or sulfates favors the reduction of platinum species on the surface of the semiconductor oxides and a better homogeneity of size and distribution of the particles of this metal. Studies were carried out in the gas phase that allowed the monitoring and quantification of the hydrogen produced from aqueous glucose solutions and it was determined that Pt-F-Nb2O5 and Pt-FTiO2 are the most efficient materials for the production of hydrogen from this substrate. Similarly, liquid phase studies were carried out with a real sample from a confectionery industry where it was determined that with the material Pt-F-Nb2O5 the highest transformation of glucose is obtained, without the formation of any other sugar or intermediate compound, indicating the preferential production of hydrogen during the photocatalytic reaction. The foregoing demonstrates the potential of the evaluated process in obtaining this gas from the recovery of polluting residues derived from the samples under study.
Nickel-Catalyzed Deuteration of Primary, Secondary, and Tertiary Silanes: Scope and Mechanistic Insights
(American Chemical Society (ACS), 2025) Laglera-Gándara, Carlos J.; Jiménez-Rioboó, Rafael; Álvarez-Rodríguez, Lucía; Peloso, Riccardo; Ríos Moreno, Pablo; Rodríguez, Amor; Química Inorgánica; Ministerio de Ciencia e Innovación (MICIN). España; Agencia Estatal de Investigación. España; European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER); Junta de Andalucía
Deuterated silanes are crucial reagents for deuteration, with a diverse range of applications in materials science, pharmaceuticals, and isotopic labeling. While most methods for synthesizing deuterated silanes rely on stoichiometric environmentally harmful processes or noble metal catalysts, research into more sustainable alternatives has received relatively less attention. In this study, we introduce a catalyst based on a nickel PBP-pincer system (PBP = bis(phosphino)boryl), which effectively facilitates catalytic hydrogen/deuterium exchange for primary, secondary, and tertiary silanes, as well as tertiary siloxanes and certain boranes, utilizing a catalyst loading of 2 mol % at 25 °C. DFT calculations identify two reaction pathways that require overcoming similar energy barriers for the H/D exchange step: silane activation assisted by the PBP ligand (ΔG⧧ = 24.1 kcal mol−1) and H/D exchange promoted by nucleophilic Ni-hydride (ΔG⧧ = 22.4 kcal mol−1). These results suggest that both pathways are feasible, with a slight energetic preference for the latter. We also present detailed mechanistic studies, including control experiments, an analysis of catalyst deactivation pathways, and kinetic studies that are in excellent agreement with the outcome of the theoretical calculations.
Direct observation of interface-dependent activity in NiO/CeO2 for effective low-temperature CO oxidation
(Elsevier, 2025-01-01) Liu, Kun; Liao, Luliang; Li, Lin; Nawaz, Muhammad Asif; Liao, Guangfu; Xu, Xianglan; Química Inorgánica; National Natural Science Foundation of China; Jiangxi Provincial Natural Science Foundation; Key Laboratory Foundation of Jiangxi Province for Environment and Energy Catalysis
In contemporary catalytic interface exploration, experimental studies often take a backseat to theoretical simulations, hindering the development of pristine catalytic interfaces. This research leverages monolayer dispersion theory to design an efficient CO oxidation catalyst through precise manipulation of non-precious metal NiOsingle bondCeO2 interfaces. Employing the pioneering XRD extrapolation method, we fabricated monolayer dispersed Ni-O-Ce and Ce-O-Ni interfaces, unlocking insights into their impact on the CO oxidation mechanism. The method accurately quantified monolayer dispersion capacities: 0.526 mmol NiO/(100 m2 CeO2) for NiO/CeO2 and 0.0638 mmol CeO2/(100 m2 NiO) for CeO2/NiO, revealing intricate interactions between active components and supports. Utilizing numerical values derived from monolayer dispersion theory, we constructed CeO2-supported NiO (Ni-O-Ce) and NiO-supported CeO2 (Ce-O-Ni) catalysts in a monolayer dispersed state. The Ni-O-Ce interface, generating abundant oxygen vacancies, significantly enhanced CO adsorption and facilitated surface reactive oxygen species production, leading to a remarkable 14-fold increase in intrinsic CO oxidation activity and a notable 4.2-fold improvement in water resistance. Integrating XRD extrapolation, H2-TPR, O2-TPD, CO-TPD, XPS, Raman, and in situ IR techniques, our study demonstrates the feasibility of crafting efficient catalysts with monolayer dispersed atomic-scale catalytic interfaces to elucidate the mechanisms underlying catalytic interface effects on CO oxidation.
Investigation of Sn Promoter on Ni/CeO2 Catalysts for Enhanced Acetylene Semihydrogenation to Ethylene
(American Chemical Society, 2024-12-11) Sun, Xueming; Wu, Rundong; Nawaz, Muhammad Asif; Meng, Shuai; Guan, Tong; Zhang, Chong; Sun, Chunyan; Lu, Zhang-Hui; Zhang, Rongbin; Feng, Gang; Ye, Runping; Química Inorgánica; Thousand Talents Plan of Jiangxi Province; Natural Science Foundation of Jiangxi Province for Distinguished Young Scholars; National Natural Science Foundation of China; Natural Science Foundation of Jiangxi Province, China
Ethylene, as an important chemical raw material, could be produced through the coal-based acetylene hydrogenation route. Nickel-based catalysts demonstrate significant activity in the semihydrogenation reaction of acetylene, but they encounter challenges related to catalyst deactivation and overhydrogenation. Herein, the effect of Sn promoter on Ni/CeO2 catalysts has been comprehensively explored for acetylene semihydrogenation. The optimized Ni/8%Sn-CeO2 catalytic performance was significantly improved, with 100% acetylene conversion and 82.5% ethylene selectivity at 250 °C, and the catalyst maintained high catalyst performance within a 1000 min stability test. A series of characterization tests show that CeO2 modified by moderate Sn4+ doping is more conducive to modulating the charge structure and geometry of the Ni active center. Additionally, the in situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy and density functional theory results indicated that catalysts doped with Sn4+ facilitated more efficient desorption of ethylene from the catalyst surface compared to Ni/CeO2 catalysts, thus improving ethylene selectivity and yield. This study highlights an effective strategy for improving the catalytic performance of rare-earth-based catalysts through the incorporation of effective metal promoters.
Oxygen vacancy-dependent low-temperature performance of Ni/CeO2 in CO2 methanation
(Royal Society of Chemistry, 2024-09-25) Liao, Luliang; Wang, Kunlei; Liao, Guangfu; Nawaz, Muhammad Asif; Liu, Kun; Química Inorgánica; Jiangxi Provincial Natural Science Foundation
The transformative power of CO2 methanation can efficiently transform greenhouse gases into high-value products, aligning with the carbon neutrality goals. However, achieving this target at low temperature requires cumbersome efforts in designing catalysts that possess high reactivity and selectivity. Focusing on understanding the pivotal role of alkaline (such as Ca) sites in catalyzing these reactions at lower temperature could be a way of strategically creating oxygen vacancies with varying activity gradients. Designing CaCe-SG via a sol–gel method in the current study to integrate Ca into the CeO2 lattice marked the highly active moderate-strength alkaline centers which resulted in the intrinsic activity soaring by an impressive 400% compared to the conventional Ni/CeO2 catalysts. Supported by H2-TPD, Raman, and XPS analyses, a crucial revelation was unveiled where Ca modification induced a surge in the dispersion of active Ni species on Ni/CaCe-SG catalysts, thereby enhancing the abundant surface oxygen vacancies. In situ infrared spectroscopy further confirmed that the modified catalyst diligently followed the reaction pathway of CO3H* → HCOO* → CH4, culminating in the CO2 methanation activity with a low-temperature catalyst via the meticulous optimization of synthesis methods that propelled the process forward to the anticipated oxygen vacancy-induced moderate-strength alkaline centers.
Reversible Bimetallic Inhibition to Modulate Selectivity During Catalysis
(American Chemical Society, 2024-12-23) Serrano Díez, Emmanuel; Pita Milleiro, Alejandra; Rangel García, Jesús; Moreno Díaz, Juan José; Roselló Merino, Marta; Campos, Jesús; Química Inorgánica; Ministerio de Ciencia e Innovación (MICIN). España; Fundación laCaixa; European Commission (EC)
Bimetallic complexes have demonstrated a great ability to enhance the activity of monometallic systems for bond activation and catalysis. In this work, we explore the opposite approach: using a second metal to passivate the activity of another by reversible bimetallic inhibition. To do so we have synthesized a family of nine electrophilic gold complexes of formula Au(PR3)(NTf2) ([NTf2]− = [N(SO2CF3)2]−) that can act as inhibitors in the semihydrogenation of terminal and internal alkynes catalyzed by the iconic iridium Vaska complex IrCl(CO)(PPh3)2. This behavior parallels the well-known passivation effect of lead over palladium in the heterogeneous Lindlard catalyst. Most gold fragments, except for the most hindered, form metal-only Lewis pairs upon combination with iridium, which have been fully characterized and exhibit distinct dative Ir → Au bonds. When applied to alkyne hydrogenation, these bimetallic structures have a clear tendency toward olefin formation, while the monometallic catalyst unselectively leads to overreduction products. Our computational studies not only provide a feasible mechanism for the Ir-only system, but also evince the active role of gold in passivating iridium by reversibly forming heterobimetallic structures that lead to enhanced selectivity.
Pyrazolone-Based Zn(II) Complexes Display Antitumor Effects in Mutant p53-Carrying Cancer Cells
(American Chemical Society, 2024-07-08) Xhafa, Sonila; Di Nicola, Corrado; Tombesi, Alessia; Pettinari, Riccardo; Pettinari, Claudio; Scarpelli, Francesca; Crispini, Alessandra; La Deda, Massimo; Galindo del Pozo, Agustín; Marchetti, Fabio; Química Inorgánica; Ministero dell'Università e della Ricerca (MUR). Italia
The synthesis and characterization of nine Schiff bases of pyrazolone ligands HLn (n = 1–9) and the corresponding zinc(II) complexes 1–9 of composition [Zn(Ln)2] (n = 1–9) are reported. The molecular structures of complexes 2, 3, 4, 8, and 9 were determined by single-crystal X-ray diffraction analysis, highlighting in all cases a distorted tetrahedral geometry around the Zn(II) ion. Density functional theory studies are performed on both the HLn ligands and the derived complexes. A mechanism of dissociation and hydrolyzation of the coordinated Schiff base ligands is suggested, confirmed experimentally by powder X-ray diffraction study and photophysical studies. Complexes 1–9 were investigated in vitro as anticancer agents, along with mutant p53 (mutp53) protein levels in human cancer cell lines carrying R175H and R273H mutp53 proteins. Only those complexes with the highest Zn(II) ion release via dissociation have shown a significant cytotoxic activity with reduction of mutp53 protein levels.
Tailoring electronic and interfacial synergy in Cu-FeGa/Al2O3 for direct CO2 hydrogenation to ethanol
(Elsevier, 2026-03-01) Huang, Shiquan; Fang, Ling; Luo, Siling; Deng, Hao; Ramírez Reina, Tomás; Zou, Guangting; Liu, Qing; Zhang, Rongbin; Fan, Maohong; Ye, Runping; Química Inorgánica; Jiangxi Provincial Natural Science Foundation. China; Thousand Talents Plan of Jiangxi Province. China; National Natural Science Foundation of China; Nanchang University. China; Key Laboratory Foundation of Jiangxi Province. China
Chemical CO2 recycling via direct CO2 hydrogenation to ethanol represents a forward-looking route to curb greenhouse gases emissions while simultaneously alleviating the pressure from fossil fuel extraction and consumption. However, this is a complex chemical process whose successful implementation requires a careful trade- off among its key reaction steps: CO2 activation, selective C-C coupling, and hydrogenation termination. Achieving optimal ethanol synthesis requires a balance of surface intermediates and promoting C-C coupling, as indicated by thermodynamic and kinetic constraints. Herein, we have developed an efficient FeGa-doped Cu/Al2O3 catalyst prepared by the sol-gel method, achieving a space-time yield of 1.48 mmol·gcat-41 1·h-1 for ethanol. The Al2O3 support could disperse Cu active sites and generate oxygen vacancies for CO2 activation. Furthermore, Fe doping and Ga modification synergistically enhance both C-C coupling capability and the non-dissociative CO activation ability of the Cu/Al2O3 catalyst, ultimately boosting CO2 conversion to ethanol. In-situ DRIFTS spectra reveal a potential catalytic mechanism for ethanol formation: CHx* species couple with non-dissociated CO* at the Cu-FeGaOx interface, followed by hydrogenation to ethanol. Overall, this work proposes a dual-promoter strategy that incorporates both Fe and Ga in a multi-competent Cu-based formulation, offering a novel approach to designing tunable catalysts for low-carbon ethanol synthesis.
Upcycling textile derived microplastics waste collected from washer and dryers to carbonaceous products using hydrothermal carbonization
(Elsevier, 2025-06-01) Parrilla Lahoz, Silvia; Jiménez Páez, Elena; Masteghin, Mateus G.; Pawlak, Joel J.; Venditti, Richard A.; Bird, Robert; Servin, Paul; Odriozola Gordón, José Antonio; Ramírez Reina, Tomás; Duyar, Melis S.; Química Inorgánica; Ministerio de Ciencia e Innovación (MICIN). España; Agencia Estatal de Investigación. España; European Union (UE); Engineering and Physical Sciences Research Council (UK)
Microplastics are an emerging pollutant of concern. Many microplastics in the waters arise from washing synthetic textiles in residential and commercial washing machines. The present research evaluated the upcycling of this waste to carbon nanomaterials by hydrothermal carbonization. Real microfiber waste was collected using commercially available washer and dryer filters, and then carbonized to yield graphene and graphite. Via temperature and residence time screening (200ºC, 250ºC, 300ºC and 1h, 4h, 8h) two temperatures of interest were detected (250ºC and 300ºC) with a residence time of 4h. For 250ºC-4h the total solid carbon yield to amorphous carbon was detected as 100% while for 300ºC-4h the total solid carbon yield to filamentous carbon (graphene/graphite) was detected as 88%. To this end, Raman spectroscopy results indicated the production of carbon nanomaterials. The results obtained in this research demonstrated that by varying the reaction conditions, carbon production can be tailored, producing amorphous carbon or graphene/graphite. This process is an intriguing method of incorporating textile residue (microfibers) into the circular economy.
A review on high-pressure heterogeneous catalytic processes for gas-phase CO2 valorization
(Elsevier, 2024-01-01) Villora Picó, Juan J.; González Arias, Judith; Pastor Pérez, Laura; Odriozola Gordón, José Antonio; Ramírez Reina, Tomás; Química Inorgánica; Ingeniería Química y Ambiental; Ministerio de Ciencia e Innovación (MICIN). España; Agencia Estatal de Investigación. España; Junta de Andalucía
This review discusses the importance of mitigating CO2 emissions by valorizing CO2 through high-pressure catalytic processes. It focuses on various key processes, including CO2 methanation, reverse water-gas shift, methane dry reforming, methanol, and dimethyl ether synthesis, emphasizing pros and cons of high-pressure operation. CO2 methanation, methanol synthesis, and dimethyl ether synthesis reactions are thermodynamically favored under high- pressure conditions. However, in the case of methane dry reforming and reverse water-gas shift, applying high pressure, results in decreased selectivity toward desired products and an increase in coke production, which can be detrimental to both the catalyst and the reaction system. Nevertheless, high-pressure utilization proves industrially advantageous for cost reduction when these processes are integrated with Fischer-Tropsch or methanol synthesis units. This review also compiles recent advances in heterogeneous catalysts design for high-pressure applications. By examining the impact of pressure on CO2 valorization and the state of the art, this work contributes to improving scientific understanding and optimizing these processes for sustainable CO2 management, as well as addressing challenges in high-pressure CO2 valorization that are crucial for industrial scaling-up. This includes the development of cost-effective and robust reactor materials and the development of low-cost catalysts that yield improved selectivity and long-term stability under realistic working environments.

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