Facile synthesis of Cu2PO4OH hierarchical nanostructures and their improved catalytic activity by a hydroxyl group

Abstract

One- and three-dimensional (1D, 3D) Cu₂PO₄OH hierarchical architectures have been successfully prepared by a facile hydrothermal method, mainly through adjusting the precursor concentrations. A possible splitting mechanism is proposed to understand the evolution from 1D to 3D hierarchical architectures. Besides, through experiments and density functional theory (DFT) calculations, we find that copper hydroxyphosphate (Cu₂PO₄OH) shows an excellent catalytic activity for the degradation of rhodamine B (RhB). This has been mainly ascribed to the contribution of hydroxyl groups contained in Cu₂PO₄OH, which favours to form more hydroxyl radicals. Moreover, both partial density of states (PDOS) and total density of states (TDOS) have confirmed that the conduction band (CB) is affected by part of the O 2p orbitals of the hydroxyls; thus the hydroxyl group is responsible for the increased band gap and the positive VB of Cu₂PO₄OH. This study suggests that new photocatalysts or photoelectric materials can be developed through introducing hydroxyl groups.