Synthesis of the 0D/3D CuO/ZnO Heterojunction with Enhanced Photocatalytic Activity

Abstract

Construction of heterojunctions has aroused great interest recently in the photocatalysis field because of the special electronic band structure and unique physicochemical properties. In this work, a novel 0D/3D CuO/ZnO heterojunction was obtained via in situ deposition of CuO nanoparticles on the flowerlike ZnO surface using the wet chemistry method. After depositing CuO nanoparticles onto the ZnO, the CuO/ZnO heterojunction exhibits enhanced visible-light harvesting and effective separation of the photogenerated electron–hole pairs compared with those in the pure ZnO. The photocatalytic removal efficiency of phenol over the CuO/ZnO heterojunction is up to 78% under the irradiation of the light, which is ∼2 and ∼4 times higher than those of the pristine ZnO and CuO, respectively. This composite also presents good durability and stability for phenol degradation in the photocatalytic reactions. Additionally, in the photodegradation system of the CuO/ZnO heterojunction, the superoxide radicals (•O2 –) and hydroxyl radicals (•OH) are confirmed as the active species by the trapping experiments. This research provides a promising way to achieve 0D/3D heterojunctions for the application in environmental purification and remedy.

AACVD Synthesis and Characterization of Iron and Copper Oxides Modified ZnO Structured Films

“…Five distinguishable curves after deconvolution were determined, as depicted in Figure 10b. In agreement with the literature [41], peak 1 at 529.5 eV is associated with the bonding between copper and O 2− (Cu-O), whereas peak 2 located at 530.7 eV is related to the Zn-O wurtzite lattice bond, as established above. Peak 3 at a binding energy of 531.7 eV is assigned to the oxygen deficiency regions, i.e., oxygen vacancies.…”

Effect of Zn Doping in CuO Octahedral Crystals towards Structural, Optical, and Gas Sensing Properties

“…After Zn doping, Cu 2p peaks were shifted to a higher binding energy side as compared with those of pure CuO particles. Higher electronegativity of Zn (1.372) as compared to that of Cu (1.336) caused lowering of the electron density around the central Cu ion by introducing oxygen and thereby results in a blue shift [37][38][39]. In the O 1s spectra, three major peaks in the range of 529 eV to 534 eV were assigned to the lattice oxygen (O L ), oxygen in the crystal matrix at the oxygen-deficient site (O V ), and surface adsorption oxygen (O S ), respectively [40].…”

Synthesis and enhanced photocatalytic performance of 0D/2D CuO/tourmaline composite photocatalysts

“…The application of CuO covers the fields of photocatalytic degradation of organic contaminants [7], photocatalytic reduction of CO 2 [8,9], photocatalytic splitting of water [10], etc. Nanoscale CuO has been widely studied owing to its increased surface defects and higher specific surface area compared with its bulk counterpart [11,12]. However, the agglomeration of nanoscale CuO results from the high surface energy and the quick recombination of the photoinduced charge carriers and restricts the photocatalytic activity [13,14].…”

“…However, the agglomeration of nanoscale CuO results from the high surface energy and the quick recombination of the photoinduced charge carriers and restricts the photocatalytic activity [13,14]. At present, the construction of CuO-based heterostructures (e.g., 0D/2D CuO/TiO 2 , 0D/3D CuO/ZnO, 2D/2D CuO/Fe 2 O 3 , 0D/2D CuO/C 3 N 4 , 2D/0D CuO/Ag 3 PO 4 ) [6,12,[15][16][17] and the dispersion of CuO on supporting materials (e.g., graphene, carbon nanotube) [7,18] are considered to be the most effective ways to address these problems. However, it is difficult to obtain uniform heterostructures, and the preparation process is either complex or of high cost.…”