Copper monodispersed

Eng used the galvanostatic deposition of monodisperse polystyrene particles onto a RCE from an acidic copper sulfate to test her theoretical predictions. The particle deposition was found to increase with current density. The increase was greatest at a rotation speed of 615 rpm, and lower at higher and lower rotation speeds. The effect of current density on particle deposition is predicted using her MEIPET boundary conditions but the effect of the rotation speed cannot be explained. 

Nearly monodisperse TOPO-capped copper sulfide nanocrystals of ca. 4.5 nm diameter have been synthesized from [Cu(S2CNMe( Hex))2]. The absorption spectrum of the (CU2S) nanoparticles shows a large blue shift (2.09 eV) in relation to bulk CU2S (1022 nm, 1.21 eV) [225]. 

Peng [4] prepared monodispersed nanoparticles between 1 and 20 nm consisting of gold, silver, copper, and platinum, which were used as high efficiency industrial catalysts. 

Another Important concept introduced by Taylor was that of heterogeneity of surface-active centers.(25-26) This stemmed from observation of R. N. Pease that minute amounts of carbon monoxide, much smaller than the amount necessary to cover the surface, were sufficient to poison the surface of a copper catalyst. Taylor proposed that there were active centers on the surface while others argued that nickel impurities segregated preferentially on the surface and acted as catalyst. The variation of the heats of adsorption with surface coverage as determined by R. Beebe was used as evidence supporting the concept of active centers. In spite of the contradictory interpretation of the same experimental data, the concept of active centers has been a fruitful one. It inspired Imaginative research in the field of metal and oxide catalysis and has its present day expression in sophisticated surface physics studies. Subsequent work by coworkers of Turkevich at Princeton refined the nature of active centers in monodisperse metal particles and crystalline oxide catalysts. 

A convenient, non-injection approach for the synthesis of kesterite CZTS nanociystals by reaction of Cu(ii), Zn(ii) and Sn(ii) chlorides with sulfur powder in ethanol solution of potassium tertiary butoxide (CHsjsCOK has been recently reported. Cu " changed to Cu" and Sn " changed to Sn during the reaction. Monodispersed nanoctystals ranging in size from 5-8 nm were obtained which had an optical band gap of 1.5 eV. EDX showed that the CZTS nanociystals had a copper poor and zinc rich stoichiometry desired for optimum performance of solar devices. 

Routes to Monodispersivity Small Crystallites. Spin-coating methods containing precursor salts can produce very small crystallites on the surface of a silicon wafer (63-W). Compounds of copper nitrate, for example, have been readily... 

Pugazhenthiran N, Anandan S, Kathiravan G, Prakash NKU, Crawford S, Ashokkumar M (2009) Microbial synthesis of silver nanoparticles by Bacillus sp. J Nanopart Res 11 1811-1815 Salvador MR, Ando RA, Oiler do Nascimento CA, Correa B (2014) Intracellular biosynthesis and removal of copper nanoparticles by dead biomass of yeast isolated from the wastewater of a mine in the Brazilian Amazonia. PLoS One 9 e87968 Sathiyadevi G, Loganathan B, Karthikeyan B (2014) Solvent-mediated eco-friendly synthesis and characterization of monodispersed bimetallic Ag/Pd nanocomposites for sensing and Raman scattering applications. J Nanosci 762453... 

Scholes and co-workers demonstrated the synthesis of monodisperse pyramidal CuInS2 (CIS) nanocrystals of ca. 3-8 nm size (Fig. 10 (a)). The reaction was performed by mixing copper and indium salts [Cul, In(02CCH3)3] with DDT, ODE followed by the addition of OA and the resultant mixture was heated to 200 °C. The structure of the as-synthesised NCs matched with tetragonal phase and IR studies indicated that the surface was capped only with DDT ligands. The PL emission of the NCs varied from visible to near-infrared region (700 900 nm) with increase in particle size. This synthetic route was easily scaled up to produce gram-quantities of CIS NCs. 

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