Synthesis of Cu₂PO₄OH Hierarchical Superstructures with Photocatalytic Activity in Visible Light

Abstract

Using a wet‐chemical method and without any surfactants or templates, various 3D hierarchical superstructures of Cu2PO4OH were synthesized by simply adjusting the pH. The resulting hierarchical superstructures were characterized using X‐ray diffraction (XRD), field‐emission scanning electron microscopy (FESEM), high resolution‐TEM (HRTEM), Fourier transform infrared spectroscopy (FTIR), Raman, and UV–Vis spectroscopy. With an increase in pH from 2.5 to 7.0, the morphology of Cu2PO4OH varied from microrods to walnut‐shaped microspheres of self‐assembled nanoparticles. A possible mechanism for the formation of the Cu2PO4OH hierarchical superstructures was also proposed. The optical properties of the Cu2PO4OH hierarchical superstructures were strongly related to their morphologies and the size of the assembled crystallites. We further demonstrated the useful photocatalytic activity of these complex structures in the degradation of methylene blue (MB) dye under visible light irradiation (λ > 410 nm). The best photocatalytic performance was achieved by Cu2PO4OH with a walnut‐shaped morphology due to the excellent absorption of visible light as well as a high BET surface area.

Tailoring high-surface-area nanocrystalline TiO2 polymorphs for high-power Li ion battery electrodes

“…When the urea concentration was low, the amorphous nanoparticles (step (i)) slowly nucleated. In the subsequent process, the OH − ions were selectively adsorbed on the hydrophilic surfaces of the particles (step (ii)), which resulted in the formation of the nanorods through the anisotropic growth (step (iii)) [28,29]. Similar rod-like brookite TiO 2 nanoparticles were previously observed by Kominami et al [16].…”

“…The surfaceadsorbed OH − and NH 4 + ions linked through the self-assembly of electrostatic attractions and repulsions, thereby producing the flower-like clusters, in Fig. 4 [29][30][31]. A previous report showed that the increased concentration of the Na + and OH − ions strengthened the assembly of the nanoparticles during the formation of the brookite TiO 2 flowers.…”

Development of plasma electrolytic oxidation for improved Ti6Al4V biomaterial surface properties

“…The experiments were carried out in an ultra-high vacuum system with a base pressure of about 6×10 −10 Pa. The XPS spectra were recorded in normal emission [10][11][12][38][39][40]. For the XPS analyses, the CasaXPS 2.3.14 software (Shirley background type) was used.…”

Copper hydroxyphosphate as catalyst for the wet hydrogen peroxide oxidation of azo dyes

“…Cho et al reported the synthesis of Cu 2 (OH)PO 4 with various 3D hierarchical superstructures by using a wet-chemical method. They demonstrated firstly the useful photocatalytic activity of these complex structures in the degradation of methylene blue dye under visible light irradiation [31]. In this paper, we investigated the wet hydrogen peroxide catalytic oxidation of an azo dye (Direct Brown 2) using Cu 2 (OH)PO 4 .…”