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Platinum is a much used catalyst that, in petrochemical processes, is often alloyed with other metals to improve catalytic activity, selectivity and longevity 1 – 5 . Such catalysts are usually prepared in the form of metallic nanoparticles supported on porous solids, and their production involves reducing metal precursor compounds under a H 2 flow at high temperatures 6 . The method works well when using easily reducible late transition metals, but Pt alloy formation with rare-earth elements through the H 2 reduction route is almost impossible owing to the low chemical potential of rare-earth element oxides 6 . Here we use as support a mesoporous zeolite that has pore walls with surface framework defects (called ‘silanol nests’) and show that the zeolite enables alloy formation between Pt and rare-earth elements. We find that the silanol nests enable the rare-earth elements to exist as single atomic species with a substantially higher chemical potential compared with that of the bulk oxide, making it possible for them to diffuse onto Pt. High-resolution transmission electron microscopy and hydrogen chemisorption measurements indicate that the resultant bimetallic nanoparticles supported on the mesoporous zeolite are intermetallic compounds, which we find to be stable, highly active and selective catalysts for the propane dehydrogenation reaction. When used with late transition metals, the same preparation strategy produces Pt alloy catalysts that incorporate an unusually large amount of the second metal and, in the case of the PtCo alloy, show high catalytic activity and selectivity in the preferential oxidation of carbon monoxide in H 2 . Alloy nanoparticles of platinum and rare-earth elements are formed using zeolites with pore-wall defects, producing stable, highly active and selective catalysts for the propane dehydrogenation reaction.

Approximately one-third of US adults have tattoos, yet the dosimetric impact of intradermal tattoo pigments during radiation therapy remains uncharacterized. Commercial tattoo inks contain unregulated metallic impurities including chromium, lead, and nickel, raising concerns about dose perturbations in tattooed skin. This work quantifies radiation dose perturbations induced by high-atomic-number (Z) tattoo pigments under clinically relevant radiotherapy conditions. Monte Carlo simulations (TOPAS) modeled layered skin phantoms with a 0.3-mm intradermal tattoo layer embedded at 1.25–1.55 mm depth. Three commercial inks were evaluated: carbon-based (black) and metal-containing (Fe-rich brown, Al-containing orange) at pigment loadings of 5–100 vol% within the tattoo layer, to establish upper-bound effects. Electron (6, 18 MeV) and photon (6, 18 MV) beams were simulated with standard clinical geometry (1 × 1 cm² field, SSD = 100 cm). Photon irradiation produced pronounced, depth-localized dose enhancement, with peak dose enhancement factor (DEF) reaching 2.5 for brown ink at 18 MV, a 62% mean increase relative to non-tattooed skin driven by high-Z–mediated secondary electron production. Electron beams exhibited energy-dependent behavior: 6 MeV produced modest enhancement (peak DEF ~ 1.07), while 18 MeV unexpectedly generated dose deficits (DEF < 1.0) due to enhanced lateral scattering. Critically, all perturbations remained depth-confined without lateral propagation, preserving spatial dose uniformity across tattooed and non-tattooed regions. Tattoo pigments containing toxic metals create substantial localized dose enhancements under photon irradiation but minimal perturbations under electron therapy. These modality-dependent effects represent a previously unrecognized source of dose uncertainty in radiotherapy and warrant consideration in treatment planning for the growing population of tattooed patients.

Silicon carbide (SiC) wafers have attracted attention as a material for advanced power semiconductor device applications due to their high bandgap and stability at high temperatures and voltages. However, the inherent chemical and mechanical stability of SiC poses significant challenges in the chemical mechanical planarization (CMP) process, an essential step in reducing defects and improving surface flatness. SiC exhibits different mechanical and chemical properties depending on SiC terminal faces, affecting SiC oxidation behavior during the CMP process. Here, we investigate the process of oxide layer formation during the CMP process and how it relates to the SiC terminal faces. The results show that under the same conditions, the C-terminated face (C-face) exhibits higher oxidation reaction kinetics than the Si-terminated face (Si-face), forming an oxide layer of finer particles. Due to the different oxidation kinetic tendencies, the oxide layer formed on the C-face has a higher friction coefficient and more defects than the oxide layer formed on the Si-face. This results in a higher removal rate during CMP for the C-face than the Si-face. Furthermore, by controlling the physicochemical properties of the oxide film, high removal rates can be achieved by friction with the pad alone, without the need for nanoparticle abrasives.

Zinc (Zn)‐based aqueous battery‐supercapacitor hybrid (BSH) devices are considered promising energy storage devices benefiting from their high energy and power densities, low‐cost, safety, and environmental benignity. However, challenges remain in the development of efficient BSH electrodes due to poor reversibility in battery electrodes and lack of efficient supercapacitor electrodes to solve the problems of low power and energy densities. Herein, the loading of iodine (I2) in the nanopores of 3D graphene‐like carbon (3DGC) for the fabrication of BSH electrodes and their device application with Zn are reported. The uniform micropores of 3DGC serve as nanocages to stabilize I2, the high surface area of 3DGC maximizes the dispersion, and the high conductivity of 3DGC provides a path for fast electron transfer. The resultant I2‐loaded 3DGC (I2/3DGC) is applied to evaluate Zn‐based battery and BSH performance. The I2/3DGC‐based electrode exhibits excellent performance with ultrahigh energy and power densities resulting from the high reversibility of I2 and supercapacitance of 3DGC. The device exhibits high cyclic stability in both battery and supercapacitor modes due to the confinement of I2 in the micropores. It is demonstrated that this combination of 3DGC with I2 provides an easy way to fabricate durable and economical BSH electrodes. A high‐performance battery–supercapacitor hybrid (BSH) electrode composed of iodine as the battery material and microporous 3D graphene‐like carbon as the supercapacitor material is developed for a Zn‐based BSH device. The BSH device indeed exhibits high energy and power densities in battery and supercapacitor modes, respectively.

Battery‐Supercapacitor Hybrids In article number 2100076, Hongjun Park, Raj Kumar Bera, and Ryong Ryoo fabricate a high‐performance battery‐supercapacitor hybrid electrode by embedding iodine in microporous 3D graphene‐like carbon. The electrically conductive framework of 3D graphene‐like carbon serves as a path for fast charge transfer. The device exhibits high energy and power densities, which is highly desirable in high‐power electronics and electric vehicles.

Amorphous carbon is widely used in energy storage and semiconductor technologies, where surface chemistry critically affects wettability, ion transport, and charge transfer. However, controlling surface oxidation remains challenging, as conventional oxidants indiscriminately modify carbon, degrading the framework and compromising performance. Here, we demonstrate a molecular‐level approach to selectively oxidize sp 2 ‐rich domains of amorphous carbon using Keggin‐type aluminum polyoxometalate (Al‐POM)‐coated silica nanoparticles. The positively charged Al 13 (OH) 32 7+ clusters electrostatically interact with sp 2 domains and release protons during structural transitions, facilitating proton‐coupled oxidation with lower activation energy. This process introduces oxygen‐containing groups, enhances interfacial charge transfer, and preserves the carbon framework. Our findings establish Al‐POM‐coated silica as a molecularly designed strategy for tailoring amorphous carbon interfaces, offering improved performance in both energy and semiconductor applications.

Silicon carbide (SiC) wafers have attracted attention as a material for advanced power semiconductor device applications due to their high bandgap and stability at high temperatures and voltages. However, the inherent chemical and mechanical stability of SiC poses significant challenges in the chemical mechanical planarization (CMP) process, an essential step in reducing defects and improving surface flatness. SiC exhibits different mechanical and chemical properties depending on SiC terminal faces, affecting SiC oxidation behavior during the CMP process. Here, we investigate the process of oxide layer formation during the CMP process and how it relates to the SiC terminal faces. The results show that under the same conditions, the C-terminated face (C-face) exhibits higher oxidation reaction kinetics than the Si-terminated face (Si-face), forming an oxide layer of finer particles. Due to the different oxidation kinetic tendencies, the oxide layer formed on the C-face has a higher friction coefficient and more defects than the oxide layer formed on the Si-face. This results in a higher removal rate during CMP for the C-face than the Si-face. Furthermore, by controlling the physicochemical properties of the oxide film, high removal rates can be achieved by friction with the pad alone, without the need for nanoparticle abrasives.

Developing effective drugs for Alzheimer’s disease (AD), the most common cause of dementia, has been difficult because of complicated pathogenesis. Here, we report an efficient, network-based drug-screening platform developed by integrating mathematical modeling and the pathological features of AD with human iPSC-derived cerebral organoids (iCOs), including CRISPR-Cas9-edited isogenic lines. We use 1300 organoids from 11 participants to build a high-content screening (HCS) system and test blood–brain barrier-permeable FDA-approved drugs. Our study provides a strategy for precision medicine through the convergence of mathematical modeling and a miniature pathological brain model using iCOs. Developing effective drugs for Alzheimer’s disease (AD), the most common cause of dementia, has been difficult because of complicated pathogenesis. Here, the authors report an efficient network-based drug-screening platform developed by integrating mathematical modeling and the pathological features of human cerebral organoids.

Electroadhesive forces are crucial in various applications, including grasping devices, electro-sticky boards, electrostatic levitation, and climbing robots. However, the design of electroadhesive devices relies on speculative or empirical error approaches. Therefore, we present a theoretical model comprising predictive coplanar electrodes and protective layers for analyzing the electrostatic fields between an object and electroadhesive device. The model considers the role of protective layer and the air gap between the electrode surface and the object. To exert a higher electroadhesive force, the higher permeability of the protective layer is required. However, a high permeability of the protective layer is hard to withstand high applied voltage. To overcome this, two materials with different permeabilities were employed as protective layers—a low-permeability inner layer and a high-permeability outer layer—to maintain a high voltage and generate a large electroadhesive force. Because a low-permeability inner layer material was selected, a more permeable outer layer material was considered. A theoretical analysis revealed complex relationships between various design parameters. The impact of key design parameters and working environments on the electroadhesion behavior was further investigated. This study reveals the fundamental principles of electroadhesion and proposes prospective methods to enhance the design of electroadhesive devices for various engineering applications.