Cu₂O polyhedra for aryl alkyne homocoupling reactions

Abstract

Cu2O cubes, octahedra and rhombic dodecahedra were employed to catalyze homo and heterocoupling reactions of aryl alkynes. X-ray diffraction (XRD) patterns of the Cu2O crystals show slight peak shifts for...

Photocatalytic activity enhancement of Cu2O cubes functionalized with 2-ethynyl-6-methoxynaphthalene through band structure modulation

“…Such XRD peak shifts have been observed before for Cu 2 O crystals. 19 This may be experimental evidence of the existence of the thin surface layer with slight bond length and bond direction deviations. These average particle sizes were used to calculate the amounts of 2E-6MN molecules needed to functionalize 10 mg of each Cu 2 O sample with 1 : 5, 1 : 10, and 1 : 100 molar ratios of surface copper atoms to 2E-6MN (see Fig.…”

“…After surface modification, the acetylenic hydrogen peak disappears for all the samples, confirming successful formation of C–Cu bonds on the Cu 2 O crystals. 19,33,38 Moreover, the C–H bond stretching peaks around 3000 cm −1 also become invisible after the molecular functionalization. The CC stretching vibration peaks and other characteristic peaks of the molecule with frequencies below 1650 cm −1 also become very weak after anchoring to the Cu 2 O crystals.…”

“…15–18 Slight bond length variations may be observable from the XRD patterns of polyhedral Cu 2 O crystals. 19 In addition to the inactivity of Au particle-decorated Cu 2 O cubes, binary semiconductor heterostructures formed between Cu 2 O cubes and ZnO, ZnS, CdS, and Ag 3 PO 4 nanostructures remain photocatalytically inert despite their favorable band energy alignments, and sometimes suppressed activities are observed for the decorated Cu 2 O octahedra and rhombic dodecahedra. 20–23 These results suggest mismatched or unfavorable interfacial band bending situations may be present depending on the contacting planes at the interface.…”

Peptide-Based Electrochemiluminescence Biosensors Using Silver Nanoclusters as Signal Probes and Pd-Cu2O Hybrid Nanoconcaves as Coreactant Promoters for Immunoassays

“…The synthesis of Cu 2 O octahedron was according to the previous method with a minor modification . In brief, 0.1 mL of CuCl 2 (0.1 M) and 0.087 g of sodium dodecyl sulfate (SDS) were successively dispersed in 9.05 mL of ultrapure water and stirred for 10 min.…”

“…The synthesis of Cu 2 O octahedron was according to the previous method with a minor modification. 27 In brief, 0.1 mL of CuCl 2 (0.1 M) and 0.087 g of sodium dodecyl sulfate (SDS) were successively dispersed in 9.05 mL of ultrapure water and stirred for 10 min. After the reaction, 200 μL of NaOH (1 M) and 650 μL of NH 2 OH•HCl (0.2 M) solution were added to the above solution and stirred sequentially for 30 s. Next, the resulting mixture was allowed to stand at room temperature for 3 h. Finally, the Cu 2 O seeds were obtained by centrifuging (8000 rpm) and washing with ethanol three times.…”