Empowering Tri-Functional Palladium's Catalytic Activity and Durability in Electrocatalytic Formic Acid Oxidation Reaction via Innovative Self-Caging and Alloying Strategies.

Direct formic acid fuel cells (DFAFCs) stand out for portable electronic devices owing to their ease of handling, abundant fuel availability, and high theoretical open circuit potential. However, the practical application of DFAFCs is hindered by the unsatisfactory performance of electrocatalysts for the sluggish anodic formic acid oxidation reaction (FAOR). Palladium (Pd) based nanomaterials have shown promise for FAOR due to their highly selective reaction mechanism, but maintaining high electrocatalytic durability remains challenging.

Reticular synthesis of two-dimensional ionic covalent organic networks as metal-free bifunctional electrocatalysts for oxygen reduction and evolution reactions.

Bifunctional electrocatalysts for the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) are the heart of metal-air batteries, fuel cells, and other energy storage systems. Here, we report a series of a novel class of redox-active viologen-based ionic covalent organic networks (vCONs) which are directly used as metal-free bifunctional electrocatalysts towards ORR and OER applications. These vCONs (named vGC, vGAC, vMEL and vBPDP) were synthesized by the well-known Zincke reaction.

Shape and Phase-Controlled One-Pot Synthesis of Air Stable Cationic AgCdS Nanocrystals, Optoelectronic and Electrochemical Hydrogen Evolution Studies.

CdS-based materials are extensively studied for photocatalytic water splitting. By incorporating Ag into CdS nanomaterials, the catalyst's charge carrier dynamic can be tuned for photo-electrochemical devices. However, photo-corrosion and air-stability of the heterostructures limit the photocatalytic device's performance.

Amorphous-Crystalline Interfaces on Hollow Nanocubes Derived from Ir-Doped Ni-Fe-Zn Prussian Blue Analog Enables High Capability of Alkaline/Acidic/Saline Water Oxidations.

Development of highly efficient and robust electrocatalysts for oxygen evolution reaction (OER) under specific electrolyte is a key to actualize commercial low-temperature water electrolyzers. Herein, a rational catalyst design strategy is first reported based on amorphous-crystalline (a-c) interfacial engineering to achieve high catalytic activity and durability under diverse electrolytes that can be used for all types of low-temperature water electrolysis. Abundant a-c interface (ACI) is implemented into a hollow nanocubic (pre)-electrocatalyst which is derived from Ir-doped Ni-Fe-Zn Prussian blue analogues (PBA).

Investigation of electrical transport properties in solution-processed BiSe-AgMnOOH nanocomposite.

In this paper, we report the fundamental electrical transport properties measured in BiSe-AgMnOOH nanocomposite disc, which is prepared for the first time by convenient low temperature solution-phase chemistry in conjunction with redox-mediated methodology. The comparative structural and morphological analyses for the nanocomposite with pristine BiSe are comprehensively investigated by different material characterization techniques. The results demonstrate the successful composite fabrication between the BiSe, Ag and γ-MnOOH components.

Colossal Dielectric Perovskites of Calcium Copper Titanate (CaCu Ti O ) with Low-Iridium Dopants Enables Ultrahigh Mass Activity for the Acidic Oxygen Evolution Reaction.

Oxygen evolution reaction (OER) under acidic conditions becomes of significant importance for the practical use of a proton exchange membrane (PEM) water electrolyzer. In particular, maximizing the mass activity of iridium (Ir) is one of the maiden issues. Herein, the authors discover that the Ir-doped calcium copper titanate (CaCu₃Ti₄O₁₂, CCTO) perovskite exhibits ultrahigh mass activity up to 1000 A g for the acidic OER, which is 66 times higher than that of the benchmark catalyst, IrO .

Degradation of mixed cationic dye pollutant by metal free melem derivatives and graphitic carbon nitride.

Graphitic carbon nitride (GCN), a polymeric metal free catalyst is widely used to degrade the toxic organic dye from the aqueous pollution. However, its catalytic efficiency and effective simultaneous reduction of mixed dye is still a challenge. Here, we have tuned the physiochemical properties of the GCN and melem derivatives by facilely tuning the degree of polycondensation and examined their catalytic activity towards the removal of cationic dye individually and together in solution.

VS: an efficient catalyst for an electrochemical hydrogen evolution reaction in an acidic medium.

In view of preparing efficient electrocatalysts for energy conversion applications, we have developed an eco-friendly, cost effective, single step method for the scalable synthesis of VS2 and its reduced graphene oxide composite VS4/rGO. Furthermore, the electrocatalytic performances of the catalysts have been studied toward the hydrogen evolution reaction in an acid medium (0.1 M H2SO4).

Bond-Energy-Driven, Low- or High-Angle-Grain-Boundary-Movement-Mediated Synthesis of Porous Se-Te for Use in Water-Splitting Reactions.

Herein, for the first time, we applied the metal-metal-bond-energy factor to the evolution of a porous Se-Te alloy. The porous Se-Te material has been prepared from the constituents' elemental states, through only a heating-cooling process in silicone oil without the use of any reagent, surfactant, or capping agent. Surprisingly, the reaction occurred at a much lower temperature (240 °C) than the mp (450 °C) of Te.

Highly Active Tungsten Oxide Nanoplate Electrocatalysts for the Hydrogen Evolution Reaction in Acidic and Near Neutral Electrolytes.

An efficient, cost-effective, and earth-abundant catalyst that could drive the production of hydrogen from water without or with little external energy is the ultimate goal toward hydrogen economy. Herein, nanoplates of tungsten oxide and its hydrates (WO·HO) as promising electrocatalysts for the hydrogen evolution reaction (HER) are reported. The square-shaped and stacked WO·HO nanoplates are synthesized at room temperature under air in ethanol only, making it as a promising green synthesis strategy.

Enhanced catalytic activity without the use of an external light source using microwave-synthesized CuO nanopetals.

We report enhanced catalytic activity of CuO nanopetals synthesized by microwave-assisted wet chemical synthesis. The catalytic reaction of CuO nanopetals and HO was studied with the application of external light source and also under dark conditions for the degradation of the hazardous dye methylene blue. The CuO nanopetals showed significant catalytic activity for the fast degradation of methylene blue and rhodamine B (RhB) under dark conditions, without the application of an external light source.

Biomolecule-assisted synthesis of In(OH)₃ nanocubes and In₂O₃ nanoparticles: photocatalytic degradation of organic contaminants and CO oxidation.

The synthesis of nanostructured materials without any hazardous organic chemicals and expensive capping reagents is one of the challenges in nanotechnology. Here we report on the L-arginine (a biomolecule)-assisted synthesis of single crystalline cubic In(OH)3 nanocubes of a size in the range of 30-60 nm along the diagonal using hydrothermal methods. Upon calcining at 750 °C for 1 h in air, In(OH)3 nanocubes are transformed into In2O3 nanoparticles (NPs) with voids.

Hierarchical nanostructured WO3-SnO2 for selective sensing of volatile organic compounds.

It remains a challenge to find a suitable gas sensing material that shows a high response and shows selectivity towards various gases simultaneously. Here, we report a mixed metal oxide WO3-SnO2 nanostructured material synthesized in situ by a simple, single-step, one-pot hydrothermal method at 200 °C in 12 h, and demonstrate its superior sensing behavior towards volatile organic compounds (VOCs) such as ammonia, ethanol and acetone. SnO2 nanoparticles with controlled size and density were uniformly grown on WO3 nanoplates by varying the tin precursor.

Egg white varnishes on ancient paintings: a molecular connection to amyloid proteins.

For about 400 years, egg white was used to coat and protect paintings without detailed understanding of its molecular properties. A molecular basis is provided for its advantageous properties and one of its protective properties is demonstrated with oxygen transport behavior. Compared to the native secondary structure of ovalbumin in solution of circa 33% α-helix and β-sheet, attenuated total reflection-FTIR (ATR-FTIR) spectra showed a 73% decrease of α-helix content and a 44% increase of β-sheet content over eight days.

Characterization of subvisible particle formation during the filling pump operation of a monoclonal antibody solution.

Characterization and control of aggregate and subvisible particle formation during fill-finish process steps are important for biopharmaceutical products. The filling step is of key importance as there is no further filtration of the drug product beyond sterile filtration. Filling processes can impact product quality by introducing physical stresses such as shear, friction, and cavitation.

Osmolyte controlled fibrillation kinetics of insulin: New insight into fibrillation using the preferential exclusion principle.

Amyloid proteins are converted from their native-fold to long beta-sheet-rich fibrils in a typical sigmoidal time-dependent protein aggregation curve. This reaction process from monomer or dimer to oligomer to nuclei and then to fibrils is the subject of intense study. The main results of this work are based on the use of a well-studied model amyloid protein, insulin, which has been used in vitro by others.

A universal pathway for amyloid nucleus and precursor formation for insulin.

To help identify the etiological agents for amyloid-related diseases, attention is focused here on the fibrillar precursors, also called oligomers and protofibrils, and on modeling the reaction kinetics of the formation of the amyloid nucleus. Insulin is a favored model for amyloid formation, not only because amyloidosis can be a problem in diabetes, but also because aggregation and fibrillation causes problems during production, storage, and delivery. Small angle neutron scattering (SANS) is used to measure the temporal formation of insulin oligomers in H(2)O- and D(2)O-based solvents and obtain consistent evidence of the composition of the insulin nucleus that comprised three dimers or six monomers similar to that recently proposed in the literature.

Viscoelastic properties of adsorbed and cross-linked polypeptide and protein layers at a solid-liquid interface.

The real-time changes in viscoelasticity of adsorbed poly(L-lysine) (PLL) and adsorbed histone (lysine rich fraction) due to cross-linking by glutaraldehyde and corresponding release of associated water were investigated using a quartz crystal microbalance with dissipation monitoring (QCM-D) and attenuated total reflection Fourier transform infrared spectroscopy (ATR/FTIR). The kinetics of PLL and histone adsorption were measured through changes in mass adsorbed onto a gold-coated quartz surface from changes in frequency and dissipation and using the Voigt viscoelastic model. Prior to cross-linking, the shear viscosity and shear modulus of the adsorbed PLL layer were approximately 3.

Surface-enhanced nucleation of insulin amyloid fibrillation.

Proteins can interact with biological surfaces such as cell membrane, chaperones, cornea, bone, arteries, veins, and heart cavities of the cardiovascular system and also with non-biological surfaces including dialysis membranes and tubing, catheters, invasive surgical instruments, needles, and artificial implants. Fibrillation of amyloid proteins is implicated in many human diseases, including Alzheimer's, Parkinson's, and type II diabetes. Here, we show that heterogeneous surfaces accelerate the human insulin nucleation process that is the rate-determining step during amyloid fibril formation.

A three-stage kinetic model of amyloid fibrillation.

Amyloid fibrillation has been intensively studied because of its association with various neurological disorders. While extensive time-dependent fibrillation experimental data are available and appear similar, few mechanistic models have been developed to unify those results. The aim of this work was to interpret these experimental results via a rigorous mathematical model that incorporates the physical chemistry of nucleation and fibril growth dynamics.

Purification of monoclonal antibodies derived from transgenic goat milk by ultrafiltration.

With the goal of recovering heterologous immunoglobulin (IgG), which comprises 10-15% of the total proteins, from transgenic goat milk at 80% yield and 80% purity, we have developed and tested a two-step membrane isolation and purification process. In the first step, reported earlier by Baruah and Belfort, microfiltration was used to fractionate the milk proteins and recover > 90% of the original IgG at a purity of about 15-20% in the permeate stream. Here, we focus on ultrafiltration (UF) to increase the purity of the target protein to 80%, while maintaining a relatively high IgG yield (80%).