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Most of the current electrocatalysts for the methanol oxidation reaction are precious group metals such as Pt, Pd, and Ru. However, their use is limited due to their high cost, scarcity, and issues with carbon monoxide poisoning. We developed a simple method to prepare a nickel foam (NF)-based monolith electrode with a NiO nanosheet array structure as an efficient electrocatalyst toward the oxidation of methanol to produce formate. By a simple ultrasonic acid treatment and air oxidation at room temperature, an inert NF was converted to NiO/NF as a catalytically active electrode due to the uniform NiO nanosheet array that was rapidly formed on the surface of NiO/NF. In alkaline electrolytes containing methanol, the as-prepared NiO/NF catalysts exhibited a lower methanol oxidation reaction (MOR) potential of +1.53 V vs RHE at 100 mA cm −2 compared to that of inert NF samples. The difference in potentials between the E MOR and the E OER at that current density was found to be 280 mV, indicating that methanol oxidation occurred at lower potentials as compared to the oxygen evolution reaction (OER). We also observed that the NiO/NF could also efficiently catalyze the oxidation of CO without being poisoned by it. NiO/NF retained close to 100% of its initial activity after 20,000 s of methanol oxidation tests at high current densities above 200 mA cm −2 . Because of the simple synthesis method and the enhanced catalytic performance and stability of NiO/NF, this allows methanol to be used as an OER masking agent for the energy-efficient generation of value-added products such as formic acid and hydrogen.

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Polydimethylsiloxane has exceptional fire retardancy characteristics, which make it a popular polymer in flame retardancy applications. Flame retardancy of polydimethylsiloxane with different nano fillers was studied. Polydimethylsiloxane composite fire property varies because of the shape, size, density, and chemical nature of nano fillers. In house made carbon and bismuth oxide nano fillers were used in polydimethylsiloxane composite. Carbon from biochar (carbonised bamboo) and a carbon by-product (carbon soot) were selected. For comparative study of nano fillers, standard commercial multiwall carbon nano tubes (functionalised, graphitised and pristine) as nano fillers were selected. Nano fillers in polydimethylsiloxane positively affects their fire retardant properties such as total smoke release, peak heat release rate, and time to ignition. Charring and surface ceramization are the main reasons for such improvement. Nano fillers in polydimethylsiloxane may affect the thermal mobility of polymer chains, which can directly affect the time to ignition. The study concludes that the addition of pristine multiwall carbon nano tubes and bismuth oxide nano particles as filler in polydimethylsiloxane composite improves the fire retardant property.

Highlights “The Islam-Pollet-Hihn process” is presented. CO 2 reduction aided by ultrasound in ambient conditions and without the use of a catalyst. A hydrocarbon yield of ca. 5% is achieved when 2% CO 2 and 98% H 2 in 1.0 M NaCl solution is sonicated. Increasing hydrogen concentration increases the yield of hydrocarbons. The CO 2 -methanation reaction may occur either by direct methanation or by radical attack induced by cavitation.