Surfactant-free synthesis of Cu2O hollow spheres and their wavelength-dependent visible photocatalytic activities using LED lamps as cold light sources

Abstract

A facile synthesis route of cuprous oxide (Cu2O) hollow spheres under different temperatures without the aid of a surfactant was introduced. Morphology and structure varied as functions of reaction temperature and duration. A bubble template-mediated formation mechanism was proposed, which explained the reason of morphology changing with reaction temperature. The obtained Cu2O hollow spheres were active photocatalyst for the degradation of methyl orange under visible light. A self-designed equipment of light emitting diode (LED) cold light sources with the wavelength of 450, 550, and 700 nm, respectively, was used for the first time in the photocatalysis experiment with no extra heat introduced. The most suitable wavelength for Cu2O to photocatalytic degradation is 550 nm, because the light energy (2.25 eV) is closest to the band gap of Cu2O (2.17 eV). These surfactant-free synthesized Cu2O hollow spheres would be highly attractive for practical applications in water pollutant removal and environmental remediation.

Electronic to protonic conduction switching in Cu2O nanostructured porous films: the effect of humidity exposure

“…[1][2][3][4] P-type semiconducting cuprous oxide (Cu 2 O) with a direct band gap of approximately 2.17 eV has been intensively investigated because of its potential application in various elds, including photovoltaic devices, light-emitting diodes, catalysis, spintronics, photoelectrochemical water splitting, and gas sensing. [5][6][7][8][9][10] The major advantages of Cu 2 O semiconductors are their nontoxicity and low cost. Electrochemical, 11 solvothermal, 12 hydrothermal, and calcination techniques 13,14 have all been reported to synthesize porous-structured Cu 2 O.…”

Precise control of Cu2O nanostructures and LED-assisted photocatalysis

“…The light source is an important factor for the photocatalytic process. While high power and intensity (hundreds of watts) are frequently engaged in photocatalytic experiments 8,13 , very little work has been reported on photocatalytic activity under low-intensity visible light sources 14 .…”

Controllable synthesis porous Ag2CO3 nanorods for efficient photocatalysis

“…The formed Ag + -PVP complex nucleate with CO 3 2− and quickly grew into uniform small Ag 2 CO 3 nanocrystal grains with preferential (300) crystal plane, while the grains are difficult to continue growing because of isolation effect results from the surface cladding by PVP. As the reaction process continues, a large number of tiny grains assemble into nanorods via the induced effect of PVP long-chain molecules [33][34][35]. Due to the isolation effect of PVP dispersing agents and the intercrystallite void of aggregation procedure, there exists pore space among adjacent Ag 2 CO 3 grains and it eventually evolves into the porous nanorod structure.…”