Fast response and recovery polyaniline montmorillonite reduce graphene oxide polymer nanocomposite material for detection of hydrogen cyanide gas.

In the present work, we have developed a polymer based gas sensor. The polymer nanocomposites are synthesized by the chemical oxidative polymerization of aniline with ammonium persulfate and sulfuric acid. The fabricated sensor is able to achieve a sensing response of 4.56% for PANI/MMT-rGO at 2 ppm of hydrogen cyanide (HCN) gas. The sensitivity of the sensors PANI/MMT and PANI/MMT-rGO are 0.89 ppm-1 and 1.1174 ppm-1 respectively. The increase in the sensitivity of the sensor may be due to an increase in the surface area provided by MMT and rGO which provided more binding sites for the HCN gas. The sensing response of the sensor increases as the concentration of the gas exposed increases but saturates after 10 ppm. The sensor recovers automatically. The sensor is stable and can work for 8 months.

Thioglycolic acid assisted hydrothermal growth of SnS 2D nanosheets as catalysts for photodegradation of industrial dyes.

We present our work on the rapid hydrothermal synthesis of highly crystalline 2D SnS nanostructures. An innovative idea is used in which thioglycolic acid is the sulfur precursor source. Structural studies indicate the material has grown in a single-phase orthorhombic structure. The single-phase formation of the material is also confirmed from the rietveld refinement of the experimental XRD data and by raman spectroscopic analysis. Morphological studies show the formation of 2D sheets having thickness in the nanoscale (100-150 nm) dimensions. Optical absorbance studies show the material is visible-light active exhibiting an indirect bandgap of 1.1 eV and direct band gap ∼1.7 eV. Density functional theory calculations support the experimental bandgap results. Photocatalytic activity of the nanosheets was investigated against methylene blue (MB), rhodamine B (RhB) and methyl orange (MO) dyes employing a solar simulator as the source of photons (light source). The nanosheets were found to photodegrade 80% of MB, 77% of RhB and 60% of MO in 120 min of light illumination. Reusability and post catalytic properties affirm the durability and stability of the nanosheets, which is very important in the context of waste water treatment considering the toxic nature of the effluents from dye industries.