Photoluminescence in the blue and green regions is observed for the first time in nanocrystals of Nd2Zr2O7 synthesized by gel combustion method. This emission is attributed to the presence of oxygen vacancies.

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Poly(vinyl alcohol), PVA, reinforced with carbon nanofillers has shown drastic variations in thermal as well as mechanical properties. In order to establish structure-property correlations, these variations have been correlated with modifications in the hydrogen bonding structure as well as the crystallinity of the PVA matrix without paying much attention to molecular packing in the amorphous region of this semicrystalline polymer. In order to investigate the molecular packing in PVA-graphene oxide (GO) nanocomposites, free volume characterization of PVA-GO nanocomposites has been carried out using ortho-positronium (o-Ps) probe. The variations in free volume size, density and size distribution have been determined through o-Ps lifetime and the corresponding intensity as well as its lifetime distribution. The variation in hydrogen bonding and its effect on crystallinity has been determined by Fourier Transform Infra Red (FTIR) and X-ray diffraction (XRD) measurements. The variation in the thermal (glass transition temperature) and mechanical (Young's modulus, tensile strength and percentage strain at break) properties of the nanocomposites is explained in view of the free volume structure and crystallinity of the PVA matrix which are severely modified due to the molecular-level dispersion of GO sheets in the PVA matrix.

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Dehydrogenation or oxidative dehydrogenation (ODH) of alkanes to produce alkenes directly from natural gas/shale gas is gaining in importance. Ti3AlC2, a MAX phase, which hitherto had not been used in catalysis, efficiently catalyzes the ODH of n‐butane to butenes and butadiene, which are important intermediates for the synthesis of polymers and other compounds. The catalyst, which combines both metallic and ceramic properties, is stable for at least 30 h on stream, even at low O2:butane ratios, without suffering from coking. This material has neither lattice oxygens nor noble metals, yet a unique combination of numerous defects and a thin surface Ti1−yAlyO2−y/2 layer that is rich in oxygen vacancies makes it an active catalyst. Given the large number of compositions available, MAX phases may find applications in several heterogeneously catalyzed reactions.