Breaking Trade‐Off between Selectivity and Activity of Nickel‐Based Hydrogenation Catalysts by Tuning Both Steric Effect and d‐Band Center

Abstract For selective hydrogenation of chemicals the high selectivity is always at the expense of activity and improving both selectivity and activity is challenging. Here, by chelating with p‐fluorothiophenol (SPhF)‐arrays, both steric and electronic effects are created to boost the performance of cheap nickel‐based catalysts. Compared with dinickel phosphide, the SPhF‐chelated one exhibits nearly 12 times higher activity and especially its selectivity is increased from 38.1% and 21.3% to nearly 100% in hydrogenations of 3‐nitrostyrene and cinnamaldehyde. Commercial catalysts like Raney Ni chelating with SPhF‐array also exhibits an enhanced selectivity from 20.5% and 23.4% to ≈100% along with doubled activity. Both experimental and density functional theory (DFT) calculation prove that the superior performance is attributed to the confined flat adsorption by ordered SPhF‐arrays and downshifted d‐band center of catalysts, leading to prohibited hydrogenation of the vinyl group and accelerative H2 activation. Such a surface modification can provide an easily‐realized and low‐cost way to design catalysts for the selective hydrogenation

Correlation between Electrolyte Chemistry and Solid Electrolyte Interphase for Reversible Ca Metal Anodes

International audienc

Microvasculature-on-a-Post Chip That Recapitulates Prothrombotic Vascular Geometries and 3D Flow Disturbance

Stenosis, characterized by partial vessel narrowing, alters blood hemodynamics and can lead to unpredictable thrombosis. Existing models struggle to accurately represent the complex vascular geometries and hemodynamics involved in such conditions. To address this challenge, a microvasculature-on-a-post chip is developed to mimic partially stenotic vascular geometries and thrombogenicity, featuring isolated 3D micropost structures with variable sizes that recreate disturbed flow profiles. To emulate the diseased vessel wall, the post microfluidics are vascularized with a confluent layer of endothelial cells. Subsequently, human blood is perfused through the endothelialized post microfluidics, observing the temporal and spatial thrombotic response governed by Virchow's triad, including vessel wall injury, hemodynamic disturbance, and hypercoagulability. The innovative model offers valuable insights into stenosis-induced thrombosis and endothelial behavior, paving the way for improved assessment of thrombotic risks associated with stenotic vessels. This advanced microfluidic platform also offers new approaches for evaluation of prothrombotic phenotypes and cardiovascular risk assessment in the future.</p