In this work, polypropylene (PP) and graphene nanoplatelet (GNPs) composites are routed through twin screw mixing and injection moulding. Two types of GNPs with a fixed size of 25 µm with surface areas ranging from 50–80 m2/g (H25, average thickness 15 nm) and 120–150 m2/g (M25, average thickness 6–8 nm) were blended with PP at loading rates of 1, 2, 3, 4, and 5 weight%. Mechanical properties such as tensile, flexural, and impact strengths and Young’s modulus (Ε) are determined. The X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), field emission scanning electron microscopy (FESEM), and polarised light microscopy (PLM) techniques are used to understand the crystallisation, thermal, dynamic mechanical, and structural behaviour of the prepared composites. The improvement of mechanical strength is observed with GNP loading for both grades. Decreasing the GNP thickness decreases the impact strength and on the other hand improves the tensile and flexural strengths and Young’s modulus. Maximum tensile (≈33 MPa) and flexural (≈58.81 MPa) strength is found for the composite carrying 5 wt% M25. However, maximum impact strength (0.197 J) is found for PP-5 wt% H25. XRD analysis confirms GNPs have an induction effect on PP’s β phase crystal structure. The PP-GNP composite exhibits better thermal stability based on determining the TD (degradation temperature), T10 (temperature at 10% weight loss), T50 (temperature at 50% weight loss), and TR (temperature at residual weight). Enhancement in melt (Tm) and crystallisation temperatures (Tc) is are observed due to a heterogeneous nucleation effect. The FESEM analysis concludes that the GNP thickness has a significant effect on the degree of dispersion and agglomeration. The smaller the thickness, the better is the dispersion and the lower is the agglomeration. Overall, the use of thinner GNPs is more advantageous in improving the polymer properties.

Graphene has accomplished huge notoriety and interest from the universe of science considering its exceptional mechanical physical and thermal properties. Graphene is an allotrope of carbon having one atom thick size and planar sheets thickly stuffed in a lattice structure resembling a honeycomb structure. Numerous methods to prepare graphene have been created throughout a limited span of time. Due to its fascinating properties, it has found some extensive applications to a wide variety of fields. So, we believe there is a necessity to produce a document of the outstanding methods and some of the novel applications of graphene. This article centres around the strategies to orchestrate graphene and its applications in an attempt to sum up the advancements that has taken place in the research of graphene.

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The present study is an attempt to discover the hydrogen storage capacity of graphene oxide-Palladium (GO-Pd) nanocomposite through Benkeser reaction. A new route has been developed to adsorb hydrogen using GO-Pd as storage medium. Graphite is oxidised using improved Hummer's method (soft chemistry synthetic route) to produce graphene oxide (GO) nanoparticles. GO-Pd composite is synthesized by ultrasonication, chemical treatment with potassium tetrachloropalladate (K 2 PdCl 4) and overnight heat treatment. The prepared GO-Pd nanocomposite is hydrogenated by using lithium, ethylene diamine in argon atmosphere under ambient conditions. The hydrogenated graphene oxide-Palladium (H-GO-Pd) nanocomposites were characterized by scanning electron microscope (SEM), Fourier transform infrared spectra (FTIR) analysis, thermo gravimetric analysis (TGA) and X-ray diffractogram analysis. The FTIR analysis reports that hydrogen is adsorbed at three positions (ortho, meta and para) of graphene. The TGA analysis is used to understand the degradation behaviour of H-GO-Pd nanocomposite. It is to be noted that the degree of hydrogenation (DH) or hydrogen storage of the prepared H-GO-Pd is 17.35 weight %. Although it is not surprising, the DH is quite higher than the previously reported values. Thus graphene oxide supported Palladium nanocomposites is a definite resource for improved hydrogenation than the earlier disclosed materials using graphene.