Polymer-graphene hybrid stabilized ruthenium nanocatalysts for the dimethylamine-borane dehydrogenation at ambient conditions

"On-Off" Control for On-Demand H2 Release upon Dimethylamineborane Hydrolysis over Ru0.8Ni0.2/MoS2 Nanohybrids

In spite of the fact that remarkable developments are achieved in the design and development of novel nanocatalysts for H₂ release upon dimethylamineborane hydrolysis, the development of an "on-off" switch for demand-based H₂ evolution upon dimethylamineborane hydrolysis is still a matter of supreme importance, however. Herein, we synthesized a string of MoS₂ nanosheet-supported RuNi bimetallic nanohybrids (Ru_xNi_1-x/MoS₂), by fixation of RuNi nanoparticles at the MoS₂ surface, for the H₂ evolution upon the hydrolysis of dimethylamineborane at 30 °C. For safely and effectively generating, transporting, and storing H₂ gas, the selective "on-off" switch for on-demand H₂ evolution upon dimethylamineborane hydrolysis over the Ru_0.8Ni_0.2/MoS₂ nanohybrid has been successfully realized by the Zn²⁺/EDTA-2Na system. In particular, the H₂ evolution is totally switched off by adding Zn(NO₃)₂. It seems that Zn²⁺ ions are attached and anchored at the Ru_0.8Ni_0.2/MoS₂ surface, inhibiting their surface-active sites, leading to the termination of H₂ evolution. Then, the H₂ generation is subsequently reactivated by adding the EDTA-2Na solution because of its excellent coordination ability with Zn²⁺ ions. This study not only offers a new and efficient RuNi nanocatalyst for dimethylamineborane hydrolysis but also proposes a new method for the demand-based H₂ production.

The Hydrogen-Storage Challenge: Nanoparticles for Metal-Catalyzed Ammonia Borane Dehydrogenation

Dihydrogen is one of the sustainable energy vectors envisioned for the future. However, the rapidly reversible and secure storage of large quantities of hydrogen is still a technological and scientific challenge. In this context, this review proposes a recent state-of-the-art on H₂ production capacities from the dehydrogenation reaction of ammonia borane (and selected related amine-boranes) as a safer solid source of H₂ by hydrolysis (or solvolysis), catalyzed by nanoparticle-based systems. The review groups the results according to the transition metals constituting the catalyst with a mention to their current cost and availability. This includes the noble metals Rh, Pd, Pt, Ru, Ag, as well as cheaper Co, Ni, Cu, and Fe. For each element, the monometallic and polymetallic structures are presented and the performances are described in terms of turnover frequency and recyclability. The structure-property links are highlighted whenever possible. It appears from all these works that the mastery of the preparation of catalysts remains a crucial point both in terms of process, and control and understanding of the electronic structures of the elaborated nanomaterials. A particular effort of the scientific community remains to be made in this multidisciplinary field with major societal stakes.

Recent developments of nanocatalyzed liquid-phase hydrogen generation

Hydrogen is the most effective and sustainable carrier of clean energy, and liquid-phase hydrogen storage materials with high hydrogen content, reversibility and good dehydrogenation kinetics are promising in view of "hydrogen economy". Efficient, low-cost, safe and selective hydrogen generation from chemical storage materials remains challenging, however. In this Review article, an overview of the recent achievements is provided, addressing the topic of nanocatalysis of hydrogen production from liquid-phase hydrogen storage materials including metal-boron hydrides, borane-nitrogen compounds, and liquid organic hydrides. The state-of-the-art catalysts range from high-performance nanocatalysts based on noble and non-noble metal nanoparticles (NPs) to emerging single-atom catalysts. Key aspects that are discussed include insights into the dehydrogenation mechanisms, regenerations from the spent liquid chemical hydrides, and tandem reactions using the in situ generated hydrogen. Finally, challenges, perspectives, and research directions for this area are envisaged.

Carbon-based ruthenium nanomaterial-based electroanalytical sensors for the detection of anticancer drug Idarubicin

In this work, a novel nanosensing platform was suggested based on ruthenium for the sensitive determination of Idarubicin anticancer drugs. Ruthenium/Vulcan carbon-based nanoparticles were synthesized ultrasonication method and then characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). The mean particle size of the nanoparticles calculated by the TEM analysis was found to be 1.98 nm ± 0.29 nm, and the Ru nanoparticles were mostly dispersed on the support material. Glassy carbon electrode (GCE) surface was modified with Ruthenium/Vulcan carbon-based nanomaterials (Ru@VC), and characterization of the nanosensor was performed using electrochemical impedance spectroscopy and cyclic voltammetry. The limit of detection (LOD) and limit of quantification (LOQ) values were found as 9.25 × 10^–9 M and 2.8 × 10^–8 M in buffer samples. To demonstrate the applicability and validity of developed nanosensor, it was used for the determination of Idarubicin in Idamen^® IV (10 mg/10 mL vial) and human serum sample. The results of recovery studies showed that the Ru@VC/GCE nanosensor was free from excipient interferences in the dosage forms of injection, and it can be successfully applied to biological samples.

A review study on blood in human coronary artery: Numerical approach

Computational fluid dynamics (CFD) study of blood flow in human coronary artery is one of the emerging fields of Biomed- ical engineering. In present review paper, Finite Volume Method with governing equations and boundary conditions are briefly discussed for different coronary models. Many researchers have come up with astonishing results related to the various factors (blood viscosity, rate of blood flow, shear stress on the arterial wall, Reynolds number, etc.) affecting the hemodynamic of blood in the right/left coronary artery. The aim of this paper is to present an overview of all those work done by the researchers to justify their work related to factors which hampers proper functioning of heart and lead to Coronary Artery Disease (CAD). Governing equations like Navier-stokes equations, continuity equations etc. are widely used and are solved using CFD solver to get a clearer view of coronary artery blockage. Different boundary conditions and blood properties published in the last ten years are summarized in the tabulated form. This table will help new researchers to work on this area.