Scalable Spray Drying Production of Amorphous V2O5–EGO 2D Heterostructured Xerogels for High-Rate and High-Capacity Aqueous Zinc Ion Batteries

Rechargeable aqueous zinc-ion batteries (ZIBs) are promising in stationary grid energy storage due to their advantages in safety and cost-effectiveness, and the search for competent cathode materials is one core task in the development of ZIBs. Herein, the authors design a 2D heterostructure combining amorphous vanadium pentoxide and electrochemically produced graphene oxide (EGO) using a fast and scalable spray drying technique. The unique 2D heterostructured xerogel is achieved by controlling the concentration of EGO in the precursor solution. Driven by the improved electrochemical kinetics, the resultant xerogel can deliver an excellent rate capability (334 mAh g−1 at 5 A g−1) as well as a high specific capacity (462 mAh g−1 at 0.2 A g−1) as the cathode material in ZIB. It is also shown that the coin cell constructed based on spray-dried xerogel can output steady, high energy densities over a broad power density window. This work provides a scalable and cost-effective approach for making high performance electrode materials from cheap sources through existing industrialized materials processing.</p

Ruthenium single-atom modulated Ti3C2Tx MXene for efficient alkaline electrocatalytic hydrogen production

Single-atoms (SAs) supported on various substrates have emerged as a new form of electrocatalysts for hydrogen evolution reaction (HER). The exfoliated MXenes possess rich defects/vacancies and surface oxygen groups, can be favorably utilized to anchor SAs. Here, we take advantage of the exfoliated Ti3C2Tx to anchor Ru-SAs on Ti3C2Tx through a wet-chemistry impregnation process. The obtained RuSA@Ti3C2Tx possesses excellent HER activity, especially under high current densities. Remarkably, RuSA@Ti3C2Tx can readily attain high current densities of 1 and 1.5 A cm−2 at low over potentials of 425.7 and 464.6 mV, respectively, demonstrating its potential for practical applications. The A1g vibration frequency shift of the Raman spectrum is innovatively used to probe the surface -OH coverage on Ti3C2Tx, providing critical information for mechanistic studies. The experimental and theoretical studies reveal that the superior HER electrocatalytic activity of RuSA@Ti3C2Tx results from the Ru-SAs enhanced H2O adsorption and dissociation, and promoted H2 formation.</p

Outcomes in Newly Diagnosed Atrial Fibrillation and History of Acute Coronary Syndromes: Insights from GARFIELD-AF

BACKGROUND: Many patients with atrial fibrillation have concomitant coronary artery disease with or without acute coronary syndromes and are in need of additional antithrombotic therapy. There are few data on the long-term clinical outcome of atrial fibrillation patients with a history of acute coronary syndrome. This is a 2-year study of atrial fibrillation patients with or without a history of acute coronary syndromes