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Recently, the development of high-performance non-platinum electrocatalysts for fuel cell applications has been gaining attention. Palladium-based nanoalloys are considered as promising candidates to substitute platinum catalysts for cathodic and anodic reactions in fuel cells. Here, we develop a facile route to synthesize dendritic palladium–copper–cobalt trimetallic nanoalloys as robust multifunctional electrocatalysts for oxygen reduction and formic acid oxidation. To the best of our knowledge, the mass activities of the dendritic Pd 59 Cu 30 Co 11 nanoalloy toward oxygen reduction and formic acid oxidation are higher than those previously reported for non-platinum metal nanocatalysts. The Pd 59 Cu 30 Co 11 nanoalloys also exhibit superior durability for oxygen reduction and formic acid oxidation as well as good antimethanol/ethanol interference ability compared to a commercial platinum/carbon catalyst. The high performance of the dendritic Pd 59 Cu 30 Co 11 nanoalloys is attributed to a combination of effects, including defects, a synergistic effect, change of d -band center of palladium, and surface strain. Fuel cells are promising for sustainable energy generation, but are limited by the performance of electrocatalysts. Here the authors synthesize dendritic palladium–copper–cobalt nanoalloys with electrocatalytic activity for oxygen reduction and formic acid oxidation as well as alcohol tolerance.

Tetrahexahedral particles (∼10 to ∼500 nanometers) composed of platinum (Pt), palladium, rhodium, nickel, and cobalt, as well as a library of bimetallic compositions, were synthesized on silicon wafers and on catalytic supports by a ligand-free, solid-state reaction that used trace elements [antimony (Sb), bismuth (Bi), lead, or tellurium] to stabilize high-index facets. Both simulation and experiment confirmed that this method stabilized the {210} planes. A study of the PtSb system showed that the tetrahexahedron shape resulted from the evaporative removal of Sb from the initial alloy—a shape-regulating process fundamentally different from solution-phase, ligand-dependent processes. The current density at a fixed potential for the electro-oxidation of formic acid with a commercial Pt/carbon catalyst increased by a factor of 20 after transformation with Bi into tetrahexahedral particles.

Designing highly active and robust platinum-free catalysts for hydrogen evolution reaction is of vital importance for clean energy applications yet challenging. Here we report highly active and stable cobalt-substituted ruthenium nanosheets for hydrogen evolution, in which cobalt atoms are isolated in ruthenium lattice as revealed by aberration-corrected high-resolution transmission electron microscopy and X-ray absorption fine structure measurement. Impressively, the cobalt-substituted ruthenium nanosheets only need an extremely low overpotential of 13 mV to achieve a current density of 10 mA cm −2 in 1 M KOH media and an ultralow Tafel slope of 29 mV dec −1 , which exhibit top-level catalytic activity among all reported platinum-free electrocatalysts. The theoretical calculations reveal that the energy barrier of water dissociation can greatly reduce after single cobalt atom substitution, leading to its superior hydrogen evolution performance. This study provides a new insight into the development of highly efficient platinum-free hydrogen evolution catalysts. Water splitting provides an appealing route to generating carbon-neutral fuel, however the scarcity and cost of platinum, often used as a catalyst, necessitates a search for alternatives. Here, authors show cobalt atoms in ruthenium nanosheets to afford excellent hydrogen production activities.

First-row, earth-abundant metals offer an inexpensive and sustainable alternative to precious-metal catalysts. As such, iron and cobalt catalysts have garnered interest as replacements for alkene and alkyne hydrofunctionalization reactions. However, these have required the use of air- and moisture-sensitive catalysts and reagents, limiting both adoption by the non-expert as well as applicability, particularly in industrial settings. Here, we report a simple method for the use of earth-abundant metal catalysts by general activation with sodium tert -butoxide. Using only robust air- and moisture-stable reagents and pre-catalysts, both known and, significantly, novel catalytic activities have been successfully achieved, covering hydrosilylation, hydroboration, hydrovinylation, hydrogenation and [2 π +2 π ] alkene cycloaddition. This activation method allows for the easy use of earth-abundant metals, including iron, cobalt, nickel and manganese, and represents a generic platform for the discovery and application of non-precious metal catalysis. NaO t Bu — an alkoxide salt — enables simple access to low-oxidation-state catalysis using sustainable first-row transition metals (Fe, Co, Mn, Ni). The approach works across a wide range of reductive alkene and alkyne functionlization reactions including hydroboration, hydrosilylation, hydrogenation, hydrovinylation and [2 π +2 π ] cyclization reactions.

Newer-generation drug-eluting stents that combine ultrathin strut metallic platforms with biodegradable polymers might facilitate vascular healing and improve clinical outcomes in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention (PCI) compared with contemporary thin strut second-generation drug-eluting stents. We did a randomised clinical trial to investigate the safety and efficacy of ultrathin strut biodegradable polymer sirolimus-eluting stents versus thin strut durable polymer everolimus-eluting stents in patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing primary PCI. The BIOSTEMI trial was an investigator-initiated, multicentre, prospective, single-blind, randomised superiority trial at ten hospitals in Switzerland. Patients aged 18 years or older with acute STEMI who were referred for primary PCI were eligible to participate. Patients were randomly allocated (1:1) to either biodegradable polymer sirolimus-eluting stents or durable polymer everolimus-eluting stents. Central randomisation was done based on a computer-generated allocation sequence with variable block sizes of 2, 4, and 6, which was stratified by centre, diabetes status, and presence or absence of multivessel coronary artery disease, and concealed using a secure web-based system. Patients and treating physicians were aware of group allocations, whereas outcome assessors were masked to the allocated stent. The experimental stent (Orsiro; Biotronik; Bülach, Switzerland) consisted of an ultrathin strut cobalt–chromium metallic stent platform releasing sirolimus from a biodegradable polymer. The control stent (Xience Xpedition/Alpine; Abbott Vascular, Abbott Park, IL, USA) consisted of a thin strut cobalt–chromium stent platform that releases everolimus from a durable polymer. The primary endpoint was target lesion failure, a composite of cardiac death, target vessel myocardial reinfarction (Q-wave and non-Q-wave), and clinically-indicated target lesion revascularisation, within 12 months of the index procedure. All analyses were done with the individual participant as the unit of analysis and according to the intention-to-treat principle. The trial was registered with ClinicalTrials.gov, number NCT02579031. Between April 26, 2016, and March 9, 2018, we randomly assigned 1300 patients (1623 lesions) with acute myocardial infarction to treatment with biodegradable polymer sirolimus-eluting stents (649 patients and 816 lesions) or durable polymer everolimus-eluting stents (651 patients and 806 lesions). At 12 months, follow-up data were available for 614 (95%) patients treated with biodegradable polymer sirolimus-eluting stents and 626 (96%) patients treated with durable polymer everolimus-eluting stents. The primary composite endpoint of target lesion failure occurred in 25 (4%) of 649 patients treated with biodegradable polymer sirolimus-eluting stents and 36 (6%) of 651 patients treated with durable polymer everolimus-eluting stents (difference −1·6 percentage points; rate ratio 0·59, 95% Bayesian credibility interval 0·37–0·94; posterior probability of superiority 0·986). Cardiac death, target vessel myocardial reinfarction, clinically-indicated target lesion revascularisation, and definite stent thrombosis were similar between the two treatment groups in the 12 months of follow-up. In patients with acute STEMI undergoing primary PCI, biodegradable polymer sirolimus-eluting stents were superior to durable polymer everolimus-eluting stents with respect to target lesion failure at 1 year. This difference was driven by reduced ischaemia-driven target lesion revascularisation in patients treated with biodegradable polymer sirolimus-eluting stents compared with durable polymer everolimus-eluting stents. Biotronik.

During the past decade, many patients had zotarolimus-eluting stents implanted, which had circular shape cobalt–chromium struts with limited radiographic visibility. The Resolute Onyx stent was developed to improve visibility while reducing strut thickness, which was achieved by using a novel composite wire with a dense platinum–iridium core and an outer cobalt–chromium layer. We did the first randomised clinical trial to assess the safety and efficacy of this often-used stent compared with the Orsiro stent, which consists of ultrathin cobalt–chromium struts. We did an investigator-initiated, assessor-blinded and patient-blinded, randomised non-inferiority trial in an allcomers population at seven independently monitored centres in Belgium, Israel, and the Netherlands. Eligible participants were aged 18 years or older and required percutaneous coronary intervention with drug-eluting stents. After guide wire passage with or without predilation, members of the catheterisation laboratory team used web-based computer-generated allocation sequences to randomly assign patients (1:1) to either the Resolute Onyx or the Orsiro stent. Randomisation was stratified by sex and diabetes status. Patients and assessors were masked to allocated stents, but treating clinicians were not. The primary endpoint was target vessel failure at 1 year, a composite of cardiac death, target-vessel-related myocardial infarction, and target vessel revascularisation, and was assessed by intention to treat (non-inferiority margin 2·5%) on the basis of outcomes adjudicated by an independent event committee. This trial is registered with ClinicalTrials.gov, number NCT02508714. Between Oct 7, 2015, and Dec 23, 2016, 2516 patients were enrolled, 2488 of whom were included in the intention-to-treat analysis (28 withdrawals or screening failures). 1243 participants were assigned to the Resolute Onyx group, and 1245 to the Orsiro group. Overall, 1765 (70·9%) participants presented with acute coronary syndromes and 1275 (51·2%) had myocardial infarctions. 1-year follow-up was available for 2478 (99·6%) patients. The primary endpoint was met by 55 (4·5%) patients in the Resolute Onyx group and 58 (4·7%) in the Orsiro group. Non-inferiority of Resolute Onyx to Orsiro was thus established (absolute risk difference −0·2% [95% CI −1·9 to 1·4]; upper limit of the one-sided 95% CI 1·1%; pnon-inferiority=0·0005). Definite or probable stent thrombosis occurred in one (0·1%) participant in the Resolute Onyx group and nine (0·7%) in the Orsiro group (hazard ratio 0·11 [95% CI 0·01–0·87]; p=0·0112). The Resolute Onyx stent was non-inferior to Orsiro for a combined safety and efficacy endpoint at 1-year follow-up in allcomers. The low event rate in both groups suggests that both stents are safe, and the very low rate of stent thrombosis in the Resolute Onyx group warrants further clinical investigation. Biotronik and Medtronic.

Drug-eluting stents combining an ultrathin cobalt-chromium stent platform with a biodegradable polymer eluting sirolimus have been shown to be non-inferior or superior to thin-strut, durable-polymer, everolimus-eluting stents in terms of 1 year safety and efficacy outcomes. In the randomised, single-blind, multicentre, non-inferiority BIOSCIENCE trial, we compared biodegradable-polymer sirolimus-eluting stents with durable-polymer everolimus-eluting stents in patients with chronic stable coronary artery disease or acute coronary syndromes. Here, we assess the final 5-year clinical outcomes of BIOSCIENCE with regards to the primary clinical outcome of target lesion failure, which was a composite of cardiac death, target vessel myocardial infarction, and clinically indicated target lesion revascularisation. The primary analysis was done by intention to treat. The BIOSCIENCE trial is registered with ClinicalTrials.gov, number NCT01443104. 2008 (95%) of 2119 patients recruited between March 1, 2012, and May 31, 2013, completed 5 years of follow-up. Target lesion failure occurred in 198 patients (cumulative incidence 20·2%) treated with biodegradable-polymer sirolimus-eluting stents and in 189 patients (18·8%) treated with durable-polymer everolimus-eluting stents (rate ratio [RR] 1·07, 95% CI 0·88–1·31; p=0·487). All-cause mortality was significantly higher in patients treated with biodegradable-polymer sirolimus-eluting stents than in those treated with durable-polymer everolimus-eluting stents (14·1% vs 10·3%; RR 1·36, 95% CI 1·06–1·75; p=0·017), driven by a difference in non-cardiovascular deaths. We observed no difference between groups in cumulative incidence of definite stent thrombosis at 5 years (1·6% in both groups; 1·02, 0·51–2·05; p=0·950). 5-year risk of target lesion failure among all-comer patients undergoing percutaneous coronary intervention is similar after implantation of ultrathin-strut, biodegradable-polymer, sirolimus-eluting stents or thin-strut, durable-polymer, everolimus-eluting stents. Higher incidences of all-cause and non-cardiovascular mortality in patients treated with biodegradable-polymer stents eluting sirolimus than in those treated with durable-polymer stents eluting everolimus warrant careful observation in ongoing clinical trials. Clinical Trials Unit of the University of Bern and Biotronik.

The generation of high-purity hydrogen via chemical reaction from hydrogen-rich materials is one of the ways in the alternative energy industry. In this approach, the utilization of catalytic materials that possess the capacity to initiate the decomposition of the starting material and the subsequent release of hydrogen is of paramount importance. In this study, nickel/cobalt-plated copper catalysts (NiCo/Cu) are presented, comprising from 4 to 90 wt.% of cobalt as catalytic materials for hydrogen generation via sodium borohydride (NaBH4) hydrolysis reaction. The NiCo/Cu catalysts were synthesized via electroless deposition from glycine-based baths, utilizing Ni2+ and Co2+ ions as metal sources and morpholine borane (MB) as the reducing compound. The catalytic performance in alkaline NaBH4 hydrolysis was found to correlate with the cobalt loading in the coating. The maximum rate of hydrogen production, which was determined to be 14.22 L min−1 gcat−1, was achieved at 343 K for a catalyst composed of 90 wt.% Co. The reaction proceeded with the activation energy of 52.5 kJ mol−1, while the catalyst exhibited high durability, preserving nearly 88% of its initial activity after five successive reaction cycles. The combination of nickel and cobalt, along with their synergistic effect and high efficiency in the borohydride hydrolysis reaction, makes them promising catalysts.

This study investigates the electroplating characteristics of Co-Zn alloy coatings with varying Zn contents (0.55 wt.%~8.8 wt.%) and their influence on intermetallic compound (IMC) formation during reactions with Sn solder. Co-Zn alloy coatings were successfully fabricated by electroplating using cobalt plating solutions with different concentrations of zinc sulfate. The results reveal anomalous co-deposition behavior, where the less noble Zn preferentially deposits over Co. Surface morphologies and microstructures evolve significantly with increasing Zn content, transitioning from columnar to dendritic structures. Zn incorporation into the Co lattice disrupts its crystallinity, leading to decreased crystallinity and partial amorphization. Liquid-state and solid-state interfacial reactions with Sn solder demonstrate that Zn content considerably influences IMC formation. In liquid-state reactions at 250 °C, lower Zn contents (0.55–4.8 wt.%) slightly enhance CoSn3 growth. It exhibits a dense layered-structure without IMC spallation. In contrast, a higher Zn content (8.8 wt.%) significantly reduces IMC formation by approximately 50% and produces a duplex structure with two distinct layers. In solid-state reactions at 160 °C, the suppression effect becomes even more pronounced. The Co-0.55Zn deposit exhibits significant inhibition of CoSn3 growth, while the Co-8.8Zn sample forms only a thin IMC layer, achieving a suppression rate exceeding 85%. These findings demonstrate that Zn doping effectively limits CoSn3 formation during solid-state reactions and improves interfacial stability.

Shorter electron mean free path, lower thermal expansion coefficient, and higher melting point compared to copper have made cobalt a promising alternative to copper in the post-Moore era. It has been extensively explored as a magnetic alloy material for downsized magnetic electronic components, storage devices, and specialized devices. Nevertheless, a lack of research on additives for cobalt plating solutions and unclear mechanism of the electroplating process, pose challenges in achieving cobalt plating layers with desired specifications. Electrodeposition with organic additives was employed to successfully producing cobalt plating layers. Electrochemical tests were performed to investigate the polarization effects of butanedione oxime (DMG), sodium 3-mercapto-2-propanesulfonate (SPS), and histidine (HIS) during cobalt electrodeposition to find out the inhibitory capacities of these additives. The adsorption behavior of the additives and interactions of the functional groups were analyzed by electron density and energy distribution of the additives based on quantum chemical calculations. The findings suggested that during the electrodeposition of cobalt, adsorption sites for molecules varied from the imine group of DMG to sulfonic acid group of SPS, and to imidazole group of HIS. HIS-assisted electrodeposition generated cobalt layer with pronounced soft magnetic properties of the lowest coercivity of 27.3 Oe and highest saturation magnetization intensity of 0.958 emu/g.