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We report here the effect of plasma treatment on multilayer graphene samples as determined by X-ray photoelectron spectroscopy and surface morphology studies with atomic force microscopy, scanning electron microscopy and transmission electron microscopy. The plasma treatment was modified to introduce controlled levels of defects and functionalities to the graphene samples to give tunable properties. The elemental composition and structure were investigated by XPS and micro Raman spectroscopy. The XPS study showed that there was a slight variation in the sp2/sp3 hybridization ratio between the plasma-treated samples and the pristine sample. Kelvin probe measurements were carried out on all the multilayer graphene samples and indicated a slight variation in the work function of the graphene samples after plasma treatment.

This report explores the controlled hierarchical synthesis of CdS nanostructure branches on Bi2S3 nanorod cores via a facile single step hydrothermal route. Morphological and structural studies reveal the formation of CdS–Bi2S3 heteroarchitecture with excellent stoichiometry between the constituent elements. The growth of CdS over Bi2S3 strongly depends on optimization of the reaction conditions, especially low PVP concentration. Furthermore, the as-synthesized CdS–Bi2S3 heteroarchitecture demonstrates multifunctionality in field emission and photoresponse. Interestingly, the CdS–Bi2S3 heteroarchitecture shows enhanced field emission properties such as low turn-on field (∼1.8 V μm−1 for 10 μA cm2), high emission current density and better current stability in comparison to Bi2S3 and other nanostructures. The as-synthesized CdS–Bi2S3 heteroarchitecture exhibits considerable response and recovery times, ∼207 ms and 315 ms, respectively in comparison to bare Bi2S3 nanostructures (∼655 ms and 678 ms). The present results demonstrate CdS–Bi2S3 heteroarchitecture as a potential candidate for future optoelectronic device applications.

The present investigation deals with temperature dependant Raman spectroscopy of electrochemically exfoliated few layer black phosphorus nanosheets. The temperature dependent study illustrates that softening of the A1g, B2g and A2g modes occurs as the temperature increases from 78 K to 573 K. The calculated temperature coefficients for the A1g, B2g and A2g modes were found to be −0.028 cm−1 K−1, −0.028 cm−1 K−1 and −0.018 cm−1 K−1 respectively. The observed phenomenon can be utilized for characterizing other emerging two-dimensional inorganic layered materials with atomic thickness.