Solution/Ammonolysis Syntheses of Unsupported and Silica-Supported Copper(I) Nitride Nanostructures from Oxidic Precursors

Herein we describe an alternative strategy to achieve the preparation of nanoscale Cu3N. Copper(II) oxide/hydroxide nanopowder precursors were successfully fabricated by solution methods. Ammonolysis of the oxidic precursors can be achieved essentially pseudomorphically to produce either unsupported or supported nanoparticles of the nitride. Hence, Cu3N particles with diverse morphologies were synthesized from oxygen-containing precursors in two-step processes combining solvothermal and solid−gas ammonolysis stages. The single-phase hydroxochloride precursor, Cu2(OH)3Cl was prepared by solution-state synthesis from CuCl2·2H2O and urea, crystallising with the atacamite structure. Alternative precursors, CuO and Cu(OH)2, were obtained after subsequent treatment of Cu2(OH)3Cl with NaOH solution. Cu3N, in the form of micro- and nanorods, was the sole product formed from ammonolysis using either CuO or Cu(OH)2. Conversely, the ammonolysis of dicopper trihydroxide chloride resulted in two-phase mixtures of Cu3N and the monoamine, Cu(NH3)Cl under similar experimental conditions. Importantly, this pathway is applicable to afford composite materials by incorporating substrates or matrices that are resistant to ammoniation at relatively low temperatures (ca. 300 °C). We present preliminary evidence that Cu3N/SiO2 nanocomposites (up to ca. 5 wt.% Cu3N supported on SiO2) could be prepared from CuCl2·2H2O and urea starting materials following similar reaction steps. Evidence suggests that in this case Cu3N nanoparticles are confined within the porous SiO2 matrix.

Synthesis of Co2FeGe Heusler alloy nanoparticles and catalysis for selective hydrogenation of propyne

Although intermetallic compounds are attracting attention of catalysis researchers, ternary intermetallic catalysts have scarcely been investigated due the difficulty of synthesizing supported nanoparticles.

Comparative Biocompatibilities of Various Sizes of AgCIT and AgPVP with their Protein Coronas Nanoparticles

Biocompatibilities of nanoparticles are crucial for biomedical applications. Diverse silver nanoparticles (5 nm, 10 nm, 20 nm, 40 nm and 80 nm) caped with citrate and polyvinylpyrrolidone (PVP) were synthesized and primed their protein coronas. Nanoparticles were characterized with UV-visible spectroscope, Dynamic light scattering (DLS) and Transmission Electron Microscope (TEM). Comparative biocompatibilities were verified and recorded using MTS techniques. Human hepatoma carcinoma HepG2) cell line was used for measuring cytotoxic effect by MTS assays. Deleterious and comparative behaviors of citrate and PVP supported nanoparticles with varied dimensions were investigated and concluded; that citrate caped nanoparticles are comparatively less toxic and independent of size than PVP supported nanoparticles, having increased cytotoxicity with increasing size. The cytotoxic effect of citrate caped and its protein coronas nanoparticles was insignificant, while the boosted concentration of PVP supported nanoparticles enhanced the toxic effect, which endorsed enlarged size and amount of PVP supported nanoparticles. As medicinal precursors, the overwhelming use of PVP nanoparticles should be avoided, and a unique protocol must be designed if its use is crucial and unavoidable.