Javier García-Martínez

Electrochemical CO₂ reduction offers a promising route for converting CO₂ into value-added chemicals and fuels; however, switching selectivity between C₂₊ and CH₄ pathways by controlling interfacial reconstruction remains challenging. Herein, we report a simple and effective interface engineering strategy to address this issue. By tuning the thickness of the silica shell on Cu₂O catalysts, the reaction pathway can be steered toward either C₂₊ products or CH₄. Two distinct core-shell catalysts, Cu₂O@tn-SiO₂ (with a thin silica shell) and Cu₂O@tk-SiO₂ (with a thick silica shell), were synthesized using a wet-chemical method with controlled ammonia addition. For Cu₂O@tn-SiO₂, the thin SiO₂ shell facilitates the formation of a Cu/Cu₂O/SiO₂ three-phase interface upon pre-reduction, favoring asymmetric coupling of *CO and *CHO intermediates and enabling C₂₊ production, with a maximum C₂₊ current density of -675.1 mA cm^-2 and a faradaic efficiency (FE) of 80.9%. In contrast, the thick SiO₂ shell in Cu₂O@tk-SiO₂ stabilizes the Cu₂O/SiO₂ interface, suppresses extensive reconstruction, and modulates the local availability and transfer of hydrogen species through Si-O-H containing interfacial sites, thereby favoring selective hydrogenation of *CHO toward CH₄ with a peak partial current density of -464.4 mA cm^-2 and an FE of 61.9%. Mechanistic studies support that the silica shell enhances structural stability, regulates intermediate adsorption, and tunes the interfacial hydrogen/water environment, collectively contributing to the observed switch in reaction pathway. This work provides a straightforward and effective strategy for designing copper-based catalysts with tunable product selectivity for practical CO₂ electroreduction.

La pertenencia de España a la Unión Internacional de Química Pura y Aplicada (IUPAC) es clave para reforzar la visibilidad y la capacidad de influencia de la química española. Hoy, la IUPAC va más allá de la estandarización del lenguaje químico y actúa como un actor central en la gobernanza científica global, impulsando estándares y proyectos internacionales en sostenibilidad, educación y transformación digital. Este artículo analiza el impacto científico, educativo y de influencia que supone para España formar parte de la IUPAC y destaca el traslado de su sede internacional a Europa, con una sede compartida entre Málaga y Roma, como un hito que consolida el papel de España y abre nuevas oportunidades de liderazgo y cooperación internacional.

We report the design, fabrication, and testing of 3D‐printed Al–stainless steel reactor‐catalyst monoliths for potassium borohydride hydrolysis. Three scaffold geometries—Gyroid, Schwarz P, and Schwarz P4534—were produced via selective laser melting. The monoliths were subjected to tailored acid and base leaching, increasing internal porosity and exposing and activating the catalytic sites. Structural and compositional analyses, including SEM‐EDX, XPS, and x‐ray diffraction (XRD), confirmed the homogeneous distribution of Al, Fe, Ni, and Cr, as well as the formation of an FeAl crystalline phase. Hydrogen release experiments at industrially relevant conditions showed that the Schwarz P and P4534 geometries gave the fastest hydrogen evolution, whereas the Gyroid structure was the slowest. This study highlights how 3D‐printed macrostructure design and surface activation can be combined to optimize metallic catalysts for a variety of applications.

We explore the integration of climate action and Sustainable Development Goals (SDGs) in the first two submissions of nationally determined contributions (NDCs) using an AI-based, human-validated framework. Our goal is to provide ex-ante evidence relevant to assessing policy adequacy. We find disparities in topics of interest with high-income countries emphasizing systemic challenges (health, SDG3) and low-income nations prioritizing the water-energy-food nexus (SDGs 6-7-12) and natural resource management (SDG15). We discuss what these diverging development trajectories imply for the Paris Agreement and the 2030 Agenda for sustainable development in terms of global inequality, sustainable finance flows and multilateral governance.

As scientific instruments and the literature generate ever larger volumes of data, machine learning (ML) has become essential for organizing, analyzing and interpreting complex information. This Perspective examines how ML accelerates discovery across disciplines, with examples such as brain mapping and exoplanet detection. It also considers situations with different levels of prior knowledge about the underlying phenomenon, outlining strategies to address limitations and exploit ML effectively. Although growing reliance on ML raises challenges for research practice and validation, it is reshaping scientific methods and expanding what can be studied. We also highlight foundation models as a promising route to faster, broader scientific discovery.

IUPAC has developed a set of guiding principles for the responsible practice of Chemistry worldwide that embrace scientific excellence and nurture a shared commitment to ethical and responsible conduct that is aligned with world needs.

We present a novel one‐pot synthesis of a luminescent hybrid aerogel that employs an alkoxysilane‐functionalized cyclometallated platinum(II) complex as both cross‐linking agent and photoactive unit. This ionic material consists entirely of cyclometallated platinum(II) cations and their corresponding PF ₆ ⁻ counterions. This method eliminates the need for external silica precursors, enabling the scalable fabrication of robust 3D silica networks with homogeneously integrated functional moieties. The aerogel features a bimodal meso‐/macroporous framework with a surface area (∼300 m ² /g) two orders of magnitude higher than its xerogel counterpart. The material exhibits NIR phosphorescence originating from ³ MMLCT transitions. Due to the synergy between its high porosity and photoluminescence, the aerogel exhibits excellent sensing capabilities toward [AuCl ₄ ] ⁻ , as evidenced by emission quenching. Experimental and theoretical studies point to an unprecedented Pt(II)···Au(III) metallophilic interaction, shedding light on the gold adsorption mechanism. Remarkably, the material fully restores its luminescent properties upon removal of gold species, enabling multiple sensing and recovery cycles, thus enhancing practical applicability. This study introduces a multifunctional hybrid platform that integrates optical functionality, structural robustness, and metal selectivity, expanding the application of smart aerogels in sustainable sensing and resource recovery.

Functionalizing bismuth with a protic ionic liquid creates a unique interface that enriches and activates CO ₂ while suppressing hydrogen evolution, thereby enabling the efficient production of formic acid solution under a dilute CO ₂ atmosphere.

Zeolite catalysts often face a fundamental trade-off between the molecular accessibility and shape-selective confinement. Here, we show that this trade-off can be mitigated by accessing kinetically stabilized crystalline FAU–CHA intermediates...