In this work, we study the electronic and chemical properties of a graphene sheet doped with S or P, by means of ab initio calculations. We consider one, two and three impurity atoms by substitution on the graphene and obtain doping formation energies of 5.78, 7.43 and 10.53eV for sulphur impurities and 2.73, 0.54 and 1.82 eV for phosphorous impurities. We find that doping induces a large local curvature that tends to increase the system local reactivity. We characterize the electronic structure by the electronic density of states, the electron localization function and the maximally localized Wannier functions. Some potential applications in electronic nanodevices are highlighted.
Copper oxide nanoparticles (CuO NPs) were synthesized in air by reducing copper (II) sulfate pentahydrate salt (CuSO4·5H2O) in the presence of sodium borohydride. The reaction was stabilized with Hexadecyltrimethylammonium bromide (CTAB) in a basic medium and using ultrasound waves. Different molar ratios of CTAB:Cu2+ and NaBH4:Cu2+ were explored, to optimize the synthesis conditions, and to study the stability, size, and Zeta potential of the colloidal suspension. Optimum conditions to generate spherical, stable, and monodispersed nanoparticles with hydrodynamic diameters of 36 ± 1.3 nm were obtained, using 16 mM CTAB and 2 M NaBH4 (molar ratios Cu2+:CTAB:NaBH4 of 1:6:10). X-ray diffraction (XRD) was implemented, and a monoclinic CuO crystal system was formed. This demonstrated a monoclinic crystal system corresponding to CuO. The diffraction peaks were identified and confirmed according to their selected area electron diffraction (SAED) patterns.