Madhuca longifolia plant mediated green synthesis of cupric oxide nanoparticles: A promising environmentally sustainable material for waste water treatment and efficient antibacterial agent.

In current years, the development of efficient green methods for synthesis of metal oxide nanomaterials has attracted a great attention to the researchers since the plant-mediated synthesis is a cost-effective and a good alternative to chemical and physical methods. An efficient and eco-friendly route has been developed for the green synthesis of CuO nanoparticles (NPs) by Madhuca longifolia plant extract which acts as a non-toxic reducing agent. X-ray diffraction studies reveal the good crystallinity of the synthesized NPs and FTIR spectra confirm the synthesis of these NPs. UV-visible absorption spectra showed that the NPs have been reached at different nano scale level depending on their synthesis procedures. TEM images indicate that as-synthesized CuO NPs are spherical in shape with their different size ranges and they show different band gap values which is confirmed by Tauc's formula. The NPs exhibit good photoluminescence property depending on their particle size and they also show excellent photocatalytic activity towards the degradation of methylene blue (MB) in presence of visible light irradiation which will be a promising material for waste water treatment. The synthesized CuO NPs show good antibacterial activity against bacterial strains namely E. coli BL21 DE3 Gram-negative, S. aureus Gram-positive and B.subtilis Gram-positive and the results have been compared against Ampicillin and Tetracycline.

A graphite-like zero gap semiconductor with an interlayer separation of 2.8 Å.

The synthesis of a highly crystalline graphite-like new material with an interlayer separation of 2.8 Å is demonstrated by re-stacking GO sheets in the form of a thin film. The optical absorption spectra and electrical data indicate that the new crystal phase is an indirect zero gap semiconductor.

Epitaxial growth of crystalline polyaniline on reduced graphene oxide.

Due to its unique electronic properties, graphene has already been identified as a promising material for future carbon based electronics. To develop graphene technology, the fabrication of a high quality P-N junction is a great challenge. Here, we describe a general technique to grow single crystalline polyaniline (PANI) films on graphene sheets using in situ polymerization via the oxidation-reduction of aniline monomer and graphene oxide, respectively, to fabricate a high quality P-N junction, which shows diode-like behavior with a remarkably low turn-on voltage (60 mV) and high rectification ratio (1880:1) up to a voltage of 0.2 V. The origin of these superior electronic properties is the preferential growth of a highly crystalline PANI film as well as lattice matching between the d-values [∼2.48 Å] of graphene and {120} planes of PANI.