Mechanistic Insights into the Synthesis of Nickel-Graphene Nanostructures for Gas Sensors.

Toxic gases are used in different types of industries and thus, present a potential health hazard. Therefore, highly sensitive gas sensing materials are essential for the safety of those operating in their environments. A process involving electrospinning polymer solutions impregnated with transition metal ions are developed to yield nanofibers that are annealed to form graphitic carbon / nickel nanoparticle-based fibers for gas sensing applications.

Bio-Inspired Functional Materials for Environmental Applications.

With the global population expected to reach 9.7 billion by 2050, there is an urgent need for advanced materials that can address existing and developing environmental issues. Many current synthesis processes are environmentally unfriendly and often lack control over size, shape, and phase of resulting materials.

Intermediate SrCoFeO Tetragonal Structure between Perovskite and Brownmillerite as a Model Catalyst with Layered Oxygen Deficiency for Enhanced Electrochemical Water Oxidation.

The generation of hydrogen in an environmentally benign way is highly essential to meet future energy demands. However, in the process of splitting water electrochemically, sluggish kinetics of the oxygen evolution reaction (OER) curtails its applicability, as it drags energy input. Herein, we synthesized Sr-Co-Fe-O oxides to optimize their OER activity by varying the Co/Fe ratio.

Rational Design of Highly Efficient Perovskite Hydroxide for Electrocatalytic Water Oxidation.

The production of hydrogen from ecofriendly renewable technologies like water electrolysis and fuel cells involves oxygen evolution reaction (OER), which plays a major role, but the slow kinetics of OER is a bottleneck of commercialization of such technologies. Herein, we have reported the formation of an efficient OER catalyst from SnCo(OH) (SCH) by leaching of Sn atoms during electrochemical OER studies. According to density functional theory calculations, adsorption of OH* species on Sn atoms is energetically more favorable than that of Co atoms, and as a result, highly active CoOOH is generated by leaching of Sn atoms from surface layers.

Cobalt tungsten oxide hydroxide hydrate (CTOHH) on DNA scaffold: an excellent bi-functional catalyst for oxygen evolution reaction (OER) and aromatic alcohol oxidation.

A material with interdisciplinary properties is of wide interest for use in environmental applications. Currently, hydrogen generation by electrolysis and formation of carbonyl derivatives from alcohols are two different fields that focus on energy and environmental applications. In this work, a new material, Cobalt Tungsten Oxide Hydroxide Hydrate (CTOHH) on deoxyribonucleic acid (DNA) scaffold having chain-like morphology has been prepared for the first time by a facile microwave heating method.

Advanced CuSn and Selenized CuSn@Cu Foam as Electrocatalysts for Water Oxidation under Alkaline and Near-Neutral Conditions.

Water electrolysis is a field growing rapidly to replace the limited fossil fuels for harvesting energy in future. In searching of non-noble and advanced electrocatalysts for the oxygen evolution reaction (OER), here we highlight a new and advanced catalyst, selenized CuSn@Cu foam, with overwhelming activity for OER under both alkaline (1 M KOH) and near-neutral (1 M NaHCO) conditions. The catalysts were prepared by a double hydrothermal treatment where CuSn is first formed which further underwent for second hydrothermal condition for selenization.

Nanosheets of Nickel Iron Hydroxy Carbonate Hydrate with Pronounced OER Activity under Alkaline and Near-Neutral Conditions.

Evaluation of unique catalysts of the iron group metals with activity in the OER region similar to that of scarce metals is of great importance to achieve sustainable production of H on a large scale. Herein, we report the unique nanosheets of nickel iron hydroxy carbonate hydrate (NiFeHCH) which were prepared through a wet-chemical route within 1 h of reaction time, acting as an efficient electrocatalyst for the oxygen evolution reaction (OER) in both alkaline and near-neutral media. The NiFeHCH was prepared with different concentrations of Fe in different ratios: 1:0.

Shape-selective synthesis of Sn(MoO4)2 nanomaterials for catalysis and supercapacitor applications.

Size and shape-selective Sn(MoO4)2 nanomaterials have been synthesized for the first time using a simple hydrothermal route by the reaction of Sn(ii) chloride salt with sodium molybdate in CTAB micellar media under stirring at 60 °C temperature for about three hours. Needle-like and flake-like Sn(MoO4)2 nanomaterials were synthesized by optimizing the CTAB to metal salt molar ratio and by controlling other reaction parameters. The eventual diameter and length of the nanoneedles are ∼100 ± 10 nm and ∼850 ± 100 nm respectively.

Bio-molecule assisted aggregation of ZnWO4 nanoparticles (NPs) into chain-like assemblies: material for high performance supercapacitor and as catalyst for benzyl alcohol oxidation.

ZnWO4 nanoparticles (NPs) that are assembled and aggregated together as chain-like morphology have been synthesized via the reaction of Zn(II) salt solution with sodium tungstate in the presence of the DNA scaffold under 5 min of microwave heating. The reaction parameters have been tuned to control the size of the individual particles and diameter of the chains. The significance of different reaction parameters and specific growth mechanism for the formation of particles is elaborated.

DNA-encapsulated chain and wire-like β-MnO2 organosol for oxidative polymerization of pyrrole to polypyrrole.

A DNA-encapsulated chain and wire-like β-MnO2 organosols have been synthesized utilizing a two-phase water-toluene extraction procedure at room temperature (RT). The β-MnO2 organosol was prepared by transferring KMnO4 and DNA from aqueous solution separately to an organic solvent (toluene) using a phase transfer catalyst, mixing both organic solutions together, and subsequent reduction with NaBH4. The eventual diameters of the MnO2 particles in chain-like and wire-like morphologies were ∼1-2 nm and ∼1.

Enhanced catalytic and SERS activities of CTAB stabilized interconnected osmium nanoclusters.

A new route for the formation of osmium nanoparticles (NPs) having different morphologies like aggregated clusters, chain-like networks, and small spheres are reported. The synthesis was done by utilizing a simple wet-chemical method at room temperature (RT) by the reaction of OsO4, cetyl trimethyl ammonium bromide (CTAB), 2,7-dihydroxynaphthalene (2,7-DHN) and NaOH under 30 min of reaction. The diameter of the individual particles in all the morphologies was ∼1-3 nm.

Enhanced catalytic and supercapacitor activities of DNA encapsulated β-MnO₂ nanomaterials.

A new approach is developed for the aqueous phase formation of flake-like and wire-like β-MnO2 nanomaterials on a DNA scaffold at room temperature (RT) within a shorter time scale. The β-MnO2 nanomaterials having a band gap energy ∼3.54 eV are synthesized by the reaction of Mn(II) salt with NaOH in the presence of DNA under continuous stirring.

DNA mediated wire-like clusters of self-assembled TiO₂ nanomaterials: supercapacitor and dye sensitized solar cell applications.

A new route for the formation of wire-like clusters of TiO₂ nanomaterials self-assembled in DNA scaffold within an hour of reaction time is reported. TiO₂ nanomaterials are synthesized by the reaction of titanium-isopropoxide with ethanol and water in the presence of DNA under continuous stirring and heating at 60 °C. The individual size of the TiO₂ NPs self-assembled in DNA and the diameter of the wires can be tuned by controlling the DNA to Ti-salt molar ratios and other reaction parameters.